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Administering the AARP Cache

12-7

Administering 
the AARP Cache

AARP allows hardware addresses to be mapped to an AppleTalk protocol 
address. AppleTalk uses dynamically assigned 24-bit addresses, unlike the 
statically-assigned 48-bit addresses used by Ethernet and token ring.

To make the address mapping process easier, AARP uses an Address 
Mapping Table (AMT). The most recently used addresses are maintained in 
the AMT. If an address is not in the AMT, AARP sends a request to the 
desired protocol address and the hardware address is added to the table 
when the destination node replies.

AARP is also responsible for registering a node’s dynamically assigned 
address on the network. This process is described below:

■

AARP randomly assigns an address.

■

AARP broadcasts AARP probe packets to this address to determine if 
another node is already using the address.

■

If there is no reply, the address becomes that node’s address.

■

If there is a reply, AARP repeats this process until an available address is 
discovered.

In the Administration Console, you can:

■

Display the cache

■

Remove entries

■

Flush the cache

Содержание LANPLEX 2500

Страница 1: ... LANPLEX 2500 EXTENDED SWITCHING USER GUIDE Part No 801 00343 000 Published November 1996 Revision 02 ...

Страница 2: ... Restricted Rights Legend Use duplication or disclosure by the Government is subject to restrictions as set forth in subparagraph c 1 ii for restricted Rights in Technical Data and Computer Software clause at 48 C F R 52 227 7013 3Com Corporation 5400 Bayfront Plaza Santa Clara California 95052 8145 For civilian agencies Restricted Rights Legend Use reproduction or disclosure is subject to restric...

Страница 3: ...ng 1 1 Using Menus 1 2 Bridge Menu 1 3 IP Menu 1 4 IPX Menu 1 5 Appletalk Menu 1 6 PART II VIRTUAL LAN TECHNOLOGY 2 VLANS ON THE LANPLEX SYSTEM About VLANs 2 1 Types of VLANs 2 1 Port Group VLANs 2 1 MAC Address Group VLANS 2 2 Application Oriented VLANS 2 2 Protocol Sensitive VLANS 2 2 LANplex Protocol Sensitive VLAN Configuration 2 3 Protocol Suite 2 3 Switch Ports 2 4 Layer 3 Addressing Informa...

Страница 4: ...d Routing Models 3 4 Traditional Bridging and Routing Model 3 4 LANplex Bridging and Routing Model 3 6 4 ROUTING WITH IP TECHNOLOGY IP Routing and the OSI Model 4 1 Elements of IP Routing 4 2 IP Addresses 4 2 Address Classes 4 3 Subnet Part of an IP Address 4 3 Router Interfaces 4 4 Routing Table 4 5 Static Routes 4 6 Dynamic Routes Using RIP 4 6 Default Route 4 7 Address Resolution Protocol ARP 4...

Страница 5: ...vironment 6 1 Internet Packet Exchange IPX 6 2 Routing Information Protocol RIP 6 3 Service Advertising Protocol SAP 6 3 How IPX Routing Works 6 4 IPX Packet Format 6 4 IPX Packet Delivery 6 6 Sending Node s Responsibility 6 6 Router s Responsibility 6 7 The Elements of IPX Routing 6 8 Router Interfaces 6 8 Routing Tables 6 8 Generating Routing Table Information 6 9 Selecting the Best Route 6 10 S...

Страница 6: ...SWITCHING FEATURES 8 ADMINISTERING VLANS Displaying VLAN Information 8 1 Defining VLAN Information 8 3 Modifying VLAN Information 8 4 Removing VLAN Information 8 5 9 ADMINISTERING IP ROUTING Administering interfaces 9 1 LIS Interfaces 9 2 Interface Characteristics 9 2 Displaying Interfaces 9 3 Defining an IP LIS Interface 9 4 Defining an IP VLAN Interface 9 6 Modifying an Interface 9 7 Removing an...

Страница 7: ...P Forwarding Address 9 19 Removing a Port or an IP Forwarding Address 9 19 Setting the BOOTP Hop Count Limit 9 20 Setting the BOOTP Relay Threshold 9 20 Enabling and Disabling IP Routing 9 20 Enabling and Disabling ICMP Router Discovery 9 21 Setting the RIP Mode 9 21 Pinging an IP Station 9 22 Displaying IP Statistics 9 23 10 ADMINISTERING IP MULTICAST ROUTING Enabling and Disabling DVMRP 10 2 Ena...

Страница 8: ...etting IPX Forwarding 11 11 Setting the RIP Mode 11 11 Setting the Enhanced RIP Mode 11 12 Setting the SAP Mode 11 13 Displaying Statistics 11 14 Displaying IPX Summary Statistics 11 14 Displaying IPX RIP Statistics 11 15 Displaying IPX SAP Statistics 11 16 Displaying IPX Forwarding Statistics 11 17 12 ADMINISTERING APPLETALK ROUTING Administering Interfaces 12 2 Displaying AppleTalk Interfaces 12...

Страница 9: ...hat Is RMON 13 1 Benefits of RMON 13 2 LANplex RMON Implementation 13 2 3Com Transcend RMON Agents 13 3 Management Information Base MIB 13 4 MIB Objects 13 4 Alarms 13 6 Setting Alarm Thresholds 13 7 Example of an Alarm Threshold 13 7 RMON Hysteresis Mechanism 13 8 PART VI APPENDIX A TECHNICAL SUPPORT On line Technical Services A 1 3Com Bulletin Board Service A 1 Access by Analog Modem A 1 Access ...

Страница 10: ...Support from 3Com A 4 Returning Products for Repair A 4 INDEX ...

Страница 11: ...ion This guide is intended for the system or network administrator who is responsible for configuring using and managing the LANplex 2500 system It assumes a working knowledge of local area network LAN operations and a familiarity with communications protocols used on interconnected LANs If the information in the release notes shipped with your product differs from the information in this guide fo...

Страница 12: ...IP mulitcast routing Chapter 10 How to administer IPX routing Chapter 11 How to administer AppleTalk routing Chapter 12 Remote Monitoring RMON Chapter 13 3Com Technical Support Appendix A If you are looking for Turn to Table 1 Notice Icons Icon Type Description Information Note Information notes call attention to important features or instructions Caution Cautions alert you to personal safety risk...

Страница 13: ...te the syntax and supply the appropriate value for example Set the date by using the following syntax mm DD yy hh mm ss xm Command indicates that all variables in the command syntax form have been supplied and you can enter the command as shown in text for example To update the system software enter the following command system software Update screen display This typeface indicates text that appea...

Страница 14: ...LANplex 2500 Administration Console User Guide Provides information about using the Administration Console to configure and manage your LANplex system Shipped with system Part No 801 00322 000 LANplex 2500 Extended Switching User Guide This book Describes how the routing protocols VLAN and RMON are implemented in the LANplex system and provides information about using the Administration Console to...

Страница 15: ...ments Your suggestions are very important to us and will help make our documentation more useful to you Please email comments about this document to 3Com at sdtechpubs_comments 3Mail 3Com com Please include the following information when commenting Document title Document part number listed on back cover of document Page number if appropriate Example LANplex 2500 Operation Guide Part No 801 00344 ...

Страница 16: ...6 ABOUT THIS GUIDE ...

Страница 17: ...g software in addition to Virtual LANs VLANs Internet Protocol IP Routing an enhanced version of IP from the standard system software IP multicast routing Classical IP routing over Asynchronous Transfer Mode ATM Internet Packet Exchange IPX routing AppleTalk routing Remote Monitoring RMON For information on how to gain access to online help to use scripts and to exit from the Administration Consol...

Страница 18: ...Ns ip Administer IP ipx Administer IPX appletalk Administer Appletalk snmp Administer SNMP analyzer Administer Roving Analysis script Run a script of console commands logout Logout of the Administration Console Type for help Select a menu option The following sections show the enhanced menus provided with Extended Switching software All other menu items appear in the LANplex 2500 Administration Co...

Страница 19: ...igure 1 1 Bridge Menu Hierarchy Top Level Menu bridge menu interface menu system display summary ethernet mode detail fddi ipFragmentation define atm ipxSnapTranslation modify bridge addressThreshold remove ip agingTime ipx stpState appletalk stpPriority snmp stpMaxAge analyzer stpHelloTime script stpForwardDelay logout stpGroupAddress port packetFilter vlan ...

Страница 20: ... example enter ip at the top level menu interface at the ip menu and then define at the interface menu Figure 1 2 IP Menu Hierarchy Top Level Menu ip menu interface menu system interface summary ethernet route detail fddi arp define atm atmArpServer modify bridge multicast remove ip udpHelper addAdvertisement ipx routing removeAdvertisement appletalk icmpRouterDiscovery addPvc snmp rip removePvc a...

Страница 21: ...menu For example to define a new IPX interface enter ipx at the top level menu interface at the ipx menu and then define at the interface menu Figure 1 3 IPX Menu Hierarchy Top Level Menu ipx menu interface menu system interface display ethernet route define fddi server modify atm forwarding remove bridge rip ip enhanced ipx sap route menu appletalk statistics display snmp static analyzer remove s...

Страница 22: ...letalk menu For example to define a new AppleTalk interface you would enter appletalk at the top level menu interface at the AppleTalk menu then define at the interface menu Figure 1 4 Appletalk Menu Hierarchy Top Level Menu appletalk menu interface menu system interface display ethernet route define fddi aarp remove atm zone bridge forwarding ip checksum route menu ipx ping display appletalk stat...

Страница 23: ...dcast domains to optimize network performance and create firewalls Form flexible user groups independent of the users physical network location Types of VLANs You can use several types of VLANs to group users These types include Port group VLANs MAC address group VLANs Application oriented VLANs Protocol sensitive VLANs Port Group VLANs Port group VLANs group together one or more switch ports This...

Страница 24: ...ented VLANS Using the LANplex filtering capability application specific traffic such as telnet traffic or FTP traffic can be filtered based on higher layer information You create this application oriented VLAN by configuring packet filters that specify data and offsets of the data within received packets For example to use a filter on a particular port for all telnet traffic create a a filter that...

Страница 25: ...nd application oriented VLANs always take precedence over protocol sensitive VLANs LANplex Protocol Sensitive VLAN Configuration The LANplex protocol sensitive VLAN configuration includes three elements protocol suite switch ports layer 3 addressing information for IP VLANs Protocol Suite The protocol suite describes which protocol entities can comprise a protocol sensitive VLAN For example LANple...

Страница 26: ...upports configuring of individual IP VLANs with network layer subnet addresses With this additional layer 3 information you can create independent IP VLANs that share the same switch ports for multiple IP VLANs Data is flooded according to both the protocol IP and the layer 3 information in the IP header to distinguish among multiple IP VLANs on the same switch port This configuration is discussed...

Страница 27: ...e initial default VLAN to form two or more subsets of switch ports If you remove the default VLAN and no other VLANs are defined for the system no flooding of traffic can occur How the LANplex System Makes Flooding Decisions Protocol sensitive VLANs directly affect how the LANplex system performs flooding Without protocol sensitive VLANs the flooding process is to forward data to all switch ports ...

Страница 28: ...nes the flooding domain for that data This case is called VLAN exception flooding This example shows how the VLAN exception flooding decision is made assuming an 18 port switch Index VLAN Ports 1 Default 1 18 2 IP 1 12 3 IPX 11 16 Data received on Is flooded on Because IP port 1 VLAN 2 IP data received matches IP VLAN on the source port IPX port 11 VLAN 3 IPX data received matches IPX VLAN on the ...

Страница 29: ...two IP VLANs can be configured for ports 1 10 as follows IP VLAN 1 Subnet 158 101 112 0 ports 1 10 IP VLAN 2 Subnet 158 101 113 0 ports 1 10 This example shows how flooding decisions are made using overlapping IP VLANs assuming a 12 port switch Data received on Is flooded on Because XNS port 1 VLAN 1 XNS data does not match any defined VLAN in the system IP port 2 VLAN 2 IP data received matches I...

Страница 30: ...n a routing interface you must first create a VLAN for that protocol and then associate it with that interface For example to create an IP interface that can route through a VLAN 1 Create an IP VLAN for a group of switch ports This IP VLAN does not need to contain layer 3 information unless you want to further restrict flooding according to the layer 3 subnet address 2 Configure an IP interface wi...

Страница 31: ...with subnet mask of 255 255 255 0 IP host interface address 157 103 54 254 with subnet mask of 255 255 255 0 Layer 2 bridging communication is still possible within an IP VLAN or router interface for the group of ports within that IP Interface s IP VLAN IP data destined for a different IP subnet uses the IP routing interface to get to that different subnet even if the destination subnet is on a sh...

Страница 32: ...ports with traffic segregated by protocol They are only aggregated over the high speed FDDI link See Figure 2 1 Example of a Protocol Sensitive VLAN Configuration IPX 1 VLAN 3 IP 1 VLAN 1 IP 2 Server IP 1 Server IP 1 IP 2 IPX 1 Power Run Processor Power Fan Temp Config Inserted ERROR PCMCIA LANplex 2500 Modem Terminal IP 1 IP 2 IPX 1 IPX 1 Server IP 2 VLAN 2 FDDI Power Run Processor Power Fan Temp...

Страница 33: ... clients share the same switch ports yet the IP and IPX traffic stays separate See Figure 2 2 Figure 2 2 A VLAN Configuration with Servers on Separate 100BASE T ports Power Run Process Power Fan Temp Config Inserted ERROR PCMCIA LANplex 2500 Modem Terminal Fast Ethernet 100 BASEt IP Server VLAN 1 2 and 3 IP Server VLAN 1 IPX Server VLAN 2 IPX IPX IPX IP IP IP VLAN 1 IP VLAN 2 IPX VLAN 1 IP VLAN 2 ...

Страница 34: ...2 12 CHAPTER 2 VLANS ON THE LANPLEX SYSTEM ...

Страница 35: ...ess of distributing packets over potentially dissimilar networks A router also called a gateway is the machine that accomplishes this task Routers are typically used to Connect enterprise networks together Connect subnetworks or client server networks to the enterprise network Figure 3 1 shows where routers are typically used in a network The LANplex system performs routing that connects subnets t...

Страница 36: ...ANplex system into such a network the system streamlines your network architecture and easily switches traffic between and within subnets over Ethernet and FDDI See Figure 3 2 Figure 3 2 Subnetted Architecture with LANplex Switching Hubs Bridge FDDI Backbone Bridge Bridge Bridge Bridge Engineering Sales Marketing Router Connecting enterprise networks Connecting subnets to the enterprise Router Rou...

Страница 37: ... term MAC address refers to a physical hardware address The term network address refers to a logical address that applies to a specific protocol Figure 3 3 Multiple Ports per Subnets with the LANplex 2500 System Because the LANplex model of bridging and routing allows several segments to be connected to the same subnet you can increase the level of segmentation in your network without having to cr...

Страница 38: ...chically on the LANplex system routing over bridging When a packet enters the system the system first tries to bridge the packet If the packet s destination network address is not on the same subnet then the system routes the packet Traditional Bridging and Routing Model The bridge or router determines whether a packet should be bridged or routed based on the protocol to which the packet belongs I...

Страница 39: ...et belongs to a recognized routing protocol so the packet is passed to the router 3 The router examines the destination network address and forwards the packet to the interface port connected to the destination subnet Figure 3 5 Routing in the Traditional Bridging and Routing Model 1 Transmitting host Destination host Interfaces ports Router Bridge 2 Networks 3 Router vs Bridge 1 Transmitting host...

Страница 40: ...rom one subnet to the other In this case the host transmits the packet to the connecting router s MAC address In the LANplex bridging routing model a packet is bridged as follows see Figure 3 6 1 The packet enters the LANplex system 2 The packet s destination MAC address is examined by the bridging layer 3 The destination MAC address does not correspond to the MAC address of one of the system port...

Страница 41: ...terface associated with the port on which the packet was received 4 The routing layer a Selects a destination interface based on the destination network address b Determines the MAC address of the next hop either the destination host or another gateway c Passes the packet back to the bridging layer 5 The bridging layer then selects a segment port based on the destination MAC address and forwards t...

Страница 42: ...3 8 CHAPTER 3 BRIDGING AND ROUTING IN THE LANPLEX SYSTEM ...

Страница 43: ... IP over ATM IP Routing and the OSI Model An IP router unlike a bridge operates at the network layer of the OSI Reference Model That is it routes packets by examining the network layer address IP address Bridges use the data link layer MAC addresses to make forwarding decisions See Figure 4 1 Figure 4 1 OSI Reference Model and IP Routing Application Layer Presentation Layer Session Layer Transport...

Страница 44: ... packets in a subnetworking environment IP addresses Router interfaces Routing tables Address Resolution Protocol ARP IP Addresses IP addresses are 32 bit addresses composed of a network part the address of the network on which the host is located and a host part the address of the host on that network See Figure 4 2 IP addresses differ from Ethernet and FDDI MAC addresses which are unique hardwar...

Страница 45: ...The class of an IP address is designated in the high order bits of the network parts of the address Subnet Part of an IP Address In some environments the IP address contains a subnet part Subnetting allows a single Class A B or C network to be further subdivided internally while still appearing as a single network to other networks The subnet part of the IP address is only visible to those hosts a...

Страница 46: ...the LANplex system s IP routing model more than one port can be connected to the same subnet Each router interface has an IP address and a subnet mask This address defines both the number of the network to which the router interface is attached and its host number on that network A router interface s IP address serves two functions The IP address is used when sending IP packets to or from the rout...

Страница 47: ...n forward the packet toward its destination The routing table consists of the following elements Destination IP Address the destination network subnet or host Subnet Mask the subnet mask corresponding to the destination IP address Metric a measure of the distance to the destination In the Routing Information Protocol RIP the metric is the number of hops Gateway the IP address of the next hop route...

Страница 48: ... reasonably stable routes Dynamic Routes Using RIP Automated methods of configuring routes help you keep up with a changing network environment allowing routes to be reconfigured quickly and reliably Interior Gateway Protocols IGP which operate within networks provide this automated method The LANplex system uses the Routing Information Protocol RIP one of the most widely used IGPs to configure it...

Страница 49: ...ARP ARP is a low level protocol used to locate the MAC address correspond ing to a given IP address This protocol allows a host or router to make its routing decisions using IP addresses while it uses MAC addresses to forward packets from one hop to the next Once the host or router knows the IP address of the next hop to the destination the host or router must translate that IP address into a MAC ...

Страница 50: ...ddress this device places its MAC address in the target hardware address field and sends the packet back to the source hardware address When the originating host or router receives the ARP reply it places the new MAC address in its ARP cache next to the corresponding IP address See Figure 4 8 Figure 4 8 Example of ARP Cache Updated with ARP Reply Once the MAC address is known the host or router ca...

Страница 51: ... sends an ICMP echo request to a specified destination If the destination receives the echo request it sends an ICMP echo reply back to the original sender This process tests whether the destination is reachable and responding and verifies that the major pieces of the transport system work The ping command is one frequently used way to invoke this process Creates more efficient routing ICMP Redire...

Страница 52: ...Servers An ATM ARP server maintains a table of IP addresses and their corresponding ATM addresses and circuit information To forward IP packets over an ATM interface the network node learns the ATM address for the corresponding IP address from the ATM ARP server Each ATM ARP server supports a single LIS You can associated two or more LISs with the same ATM network but each LIS operates independent...

Страница 53: ...s and all subsequent packets to the destination address The sending node adds this VC to its ATM ARP cache IP Routing References Comer Douglas E Internetworking with TCP IP Volume I Principles Protocols and Architecture Englewood Cliffs New Jersey Prentice Hall Inc 1991 Perlman Radia Interconnections Bridges and Routers Reading Massachusetts Addison Wesley Publishing Company Inc 1992 Sterns Richar...

Страница 54: ...4 12 CHAPTER 4 ROUTING WITH IP TECHNOLOGY ...

Страница 55: ...ast support within the LANplex system has two main components Internet Group Management Protocol IGMP Distance Vector Multicast Routing Protocol DVMRP This chapter describes these two protocols as well as the algorithms that the LANplex system uses for multicast routing IGMP The LANplex system is capable of dynamic multicast filtering based on the Internet Group Management Protocol IGMP This proto...

Страница 56: ...ction to a multicast router The MBONE The MBONE is an experimental Multicast Backbone network that exists on the Internet Users can test multicast applications and technology on the MBONE without waiting for Internet multicast standards to be set You can gain access to the MBONE through any Internet service provider The MBONE routers forward mulitcast packets over an interface or over a multicast ...

Страница 57: ...de discards it The flooding algorithm is useful in situations where the most important requirement for the network is robustness It does not depend on any kind of routing tables Destinations will receive packets as long as at least one path to them exists and no errors occur during transmission Spanning Trees The Spanning Tree algorithm detects loops and logically blocks redundant paths in the net...

Страница 58: ...d to avoid duplicate paths on multi access links It uses a routing table to compute a logical spanning tree for each network source The RPF algorithm has these basic steps 1 When the system receives a multicast packet the algorithm notes the source network of the packet and the interface on the LANplex system that received the packet 2 If the interface belongs to the shortest path towards the sour...

Страница 59: ... The message tells the router to send no further packets to this group In the LANplex system the Administration Console IP multicast CacheDisplay includes information about when pruning will occur on the spanning tree Multicast Interfaces Multicast interfaces on the LANplex system have several characteristics which are described in this section DVMRP Metric Value The DVMRP metric value determines ...

Страница 60: ... between two multicast routers through one or more unicast routers The multicast router at the local endpoint of the tunnel encapsulates multicast packets in a format that unicast routers can interpret and forward The multicast router at the remote endpoint decapsulates the packets into their multicast format Tunnels are virtual links through the unicast IP network Multicast tunnels have character...

Страница 61: ...rk System XNS TM a networking system developed by Xerox Corporation The NetWare operating system is based on a client server architecture where clients request certain services from servers such as file access and printer access As a network operating system environment the NetWare operating system specifies the upper five layers of the OSI reference model It provides file and printer sharing and ...

Страница 62: ...ust be provided by protocols above IPX IPX defines internetwork and intranode addressing schemes IPX internetwork addressing is based on network numbers that are assigned to each interface in an IPX network IPX intranode addressing is in the form of socket numbers Since several processes are normally operating within a node socket numbers provide a type of mail slot so that each process can distin...

Страница 63: ...nging network service information Through SAP servers advertise their services and addresses Routers gather this information and share it with other routers This strategy allows routers to dynamically create and maintain a database server table of network service information Clients on the network can determine what services are available and obtain the network address of the nodes servers where t...

Страница 64: ...bes the information included in an IPX packet that helps it get delivered and then it describes the IPX packet delivery process IPX Packet Format The IPX packet format consists of two parts a 30 byte header and a data portion The network node and socket address for both the destination and source are held within the packet s IPX header Figure 6 2 shows the IPX packet format Figure 6 2 IPX Packet F...

Страница 65: ... s information Destination Network This 4 byte field provides the destination node s network number When a sending node sets this field to zero the destination node is assumed to be on the same local segment as the sending node Destination Node This 6 byte field contains the physical address of the destination node Destination Socket This 2 byte field contains the socket address of the packet s de...

Страница 66: ... the same network number the sending node can simply address and send packets directly to the destination node However if the sending and receiving nodes have different network numbers the sending node must find a router on its own network segment that can forward packets to the destination node s network segment Network 000000AA Node 000000000001 Socket 4003 Node Node 000000000020 000000000021 Ne...

Страница 67: ...ter is directly connected the router performs the following tasks Places the destination node address from the IPX header in the destination address field of the MAC header Places its own node address in the source address field of the MAC header Increments the Transport Control field of the IPX header and transmits the packet on the destination node segment If the packet is destined for a network...

Страница 68: ...ress serves two functions It is used when sending IPX packets to or from the router itself It defines the network number of the segment connected to that interface Routing Tables A routing table holds information about all the network segments It allows a router to send a packet toward its ultimate destination using the best possible route The routing information table contains an entry for every ...

Страница 69: ... uses RIP to exchange information with other routers Routes are recalculated at regular intervals Static Routes A static route is one you manually configure in the routing table Static routes are useful in environments where no routing protocol is used or where you want to override some of the routes generated with a routing protocol Because static routes do not automatically change in response to...

Страница 70: ...to a network when choosing between alternate routes Select the route that requires the lowest number of ticks If multiple routes exist with an equal number of ticks select the route that also has the lowest number of hops If multiple routes exist with both ticks and hops equal choose any of the routes as the best route Service Advertising Protocol The Service Advertising Protocol SAP allows server...

Страница 71: ...s of a certain type on the internetwork A response to a workstation or a router request Periodic broadcasts by servers and routers Changed server information broadcasts Figure 6 5 provides an overview of the SAP packet structure Note that the packet structure is encapsulated within the data area of IPX Figure 6 5 SAP Packet Structure SAP Packet Structure Operation 2 bytes Server Entry 1 64 bytes S...

Страница 72: ...etwork Network Address This 4 byte field contains the server s network address Node Address This 6 byte field contains the server s node address Socket Address This 2 byte field contains the socket number that the server uses to receive service requests Hops to Server This 2 byte field indicates the number of intermediate networks that must be passed through to reach the server associated with thi...

Страница 73: ...provides the following information Interface Indicates from which interface the information was received Server Name The name of the server Server Type Indicates the type of service provided Network Address The address of the network on which the server resides Node Address The node of the server Socket Address The socket number on which the server will receive service requests Hops to Server The ...

Страница 74: ...P agents store this information in the server information table Clients can then use the table to contact the nearest router or file server SAP agent for server information Server Information Maintenance When a router s SAP agent receives a SAP broadcast response indicating a change in the internetwork server configuration the agent must update its server information table and inform other SAP age...

Страница 75: ... internetwork SAP Request Handling When a SAP agent receives a general request it sends the sending source a SAP response packet containing information about all servers of any type known to the receiving SAP agent This response includes the same information sent out in a periodic broadcast When the request is specific the SAP agent sends a SAP response directly to the requesting node This respons...

Страница 76: ...6 16 CHAPTER 6 ROUTING WITH IPX ...

Страница 77: ...gether to provide file sharing and printer sharing as well as applications like electronic mail and database access All Macintosh computers have AppleTalk connectivity options built into them making it the de facto standard for Apple computer networks AppleTalk Network Elements An AppleTalk network consists of different nodes in groups of networks in an AppleTalk internet These nodes can include w...

Страница 78: ...a range such as 15 through 20 This numbering scheme allows for as many as 16 580 608 nodes although the actual cables will not support this many nodes AppleTalk Nodes A node in a AppleTalk network is any addressable device including workstations printers and routers Nodes are physically attached to a network Each AppleTalk node is identified by a unique AppleTalk address that each node selects at ...

Страница 79: ... internet Administration Accounting and Marketing Network 20 40 includes two nodes in the Administration zone and five nodes in the Accounting zone Network 47 47 includes a node from the Accounting zone as well as the Marketing nodes Network 8 8 consists of nodes in the Administration zone only Creating zones within a network reduces the amount of searching a router has to do to find a resource on...

Страница 80: ...nsole A nonseed router listens for a seed router and then takes the configuration information from the first seed router it detects After a nonseed router obtains the configuration information it can participate in the network as if it were a seed router as well AppleTalk Protocols AppleTalk protocols work together to ensure the seamless flow of information throughout the AppleTalk internet Figure...

Страница 81: ...rovides the interface between the network hardware and the upper layers of the protocol stack The AppleTalk data link layer includes three link access protocols LAPs TokenTalk LAP TLAP Ethernet LAP ELAP and LocalTalk Link Access Protocol LLAP The AppleTalk Address Resolution Protocol AARP which translates hardware addresses to AppleTalk addresses also exists at the datalink layer Application Prese...

Страница 82: ...rconnected networks can exchange packets with each other End to End Services The transport layer and the session layer provide end to end services in the AppleTalk network These services ensure that routers transmit data accurately between one another Each layer includes four protocols that work together to support these services This section describes these protocols and provides more detail for ...

Страница 83: ...rk The routing table contains an entry for each network that a datagram can reach within 15 hops of the router The table is aged at set intervals as follows 1 After a period of time the RTMP changes the status of an entry from good to suspect 2 After an additional period of time the RTMP changes the status of an entry from suspect to bad 3 After an additional period of time the RTMP changes the st...

Страница 84: ...ho the datagram to the sending node This protocol can determine whether a node is accessible before any sessions are started and it can enable users to estimate the round trip delay time between two nodes Table 7 1 The Routing Table for Router 24 in Figure 7 3 Network Range Distance Interface State 5 5 1 2 Good 12 12 3 3 Good 18 20 2 3 Good 103 103 0 1 Good 64 64 1 3 Good Network 5 5 Network 64 64...

Страница 85: ...lk Data Stream Protocol ADSP AppleTalk Session Layer Protocol ASP Printer Access Protocol PAP The Zone Information Protocol ZIP ZIP works with RTMP to maintain a table that maps network numbers to network zones for the entire AppleTalk internet Network zones are the logical groupings of AppleTalk networks As we have seen it the table created by ZIP is called the Zone Information Table ZIT The Admi...

Страница 86: ...on of the job Like other protocols at the session layer PAP relies on NBP to find the addresses of named entities PAP also depends on ATP for sending data Presentation Layer The presentation layer maintains information about files formats and translations between formats An AppleTalk internet has two protocols at the presentation layer the AppleTalk Filing Protocol AFP and PostScript AFP provides ...

Страница 87: ...are addresses and their corresponding AARP addresses If an address is not in this table AARP sends a request to the protocol address and adds the hardware address to the table when the destination node replies You can view this table called the AARP cache through the LANplex Administration Console ...

Страница 88: ...7 12 CHAPTER 7 ROUTING IN AN APPLETALK ENVIRONMENT ...

Страница 89: ...bnets The detailed VLAN report includes the summary information plus additional utilization statistics From the top level of the Administration Console enter bridge vlan summary or bridge vlan detail The VLAN information is displayed in the format you specified Example of a summary display for several VLANs Select menu option bridge vlan summary Index Protocol Identifier Ports 1 default 0 1 17 2 I...

Страница 90: ...nPackets inBytes outPackets outBytes 1 342 3676 322 2987 2 125 7654 118 6897 3 345 7554 289 7431 4 876 8651 765 7969 Table 8 1 describes these statistics Table 8 1 Fields for VLAN Information Field Description Index A system assigned index used for identifying a particular VLAN Protocol The protocol suite of the VLAN Identifier A unique user defined 4 byte integer for use by global management oper...

Страница 91: ... 1 Enter defined to use layer 3 subnet addressing and continue with steps 2 and 3 OR enter undefined to not use layer 3 addressing 2 Enter the IP subnet address 3 Enter the subnet mask Field Description inPackets Number of flooded broadcast and multicast packets that were received on the VLAN inBytes Number of flooded broadcast and multicast bytes that were received on the VLAN outPackets Number o...

Страница 92: ...mation that defines the VLAN Press the Return or Enter key to accept any value that appears in brackets 2 Enter the number of the VLAN interface index 3 Enter the protocol suite for that VLAN IP IPX AppleTalk XNS DECnet SNA Banyan X 25 NetBIOS NetBEUI default 4 Enter the VLAN identifier 5 Enter the VLAN name 6 Enter the number s of the port s or all 7 If you have selected the IP protocol suite and...

Страница 93: ...on Follow these steps to remove a VLAN definition 1 From the top level of the Administration Console enter bridge vlan remove 2 Enter the indexes for the VLANs you want to remove Example Select menu option bridge vlan remove Select VLAN index es 1 2 all 1 Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout display mode ipFragmentation ipxSnapTranslation addr...

Страница 94: ...8 6 CHAPTER 8 ADMINISTERING VLANS ...

Страница 95: ...tocol RIP Ping IP statistics Administering interfaces You can define two types of IP interfaces through LANplex Extended Switching software IP VLAN interfaces and IP LIS interfaces This section describes these interfaces and how to administer them An IP VLAN interface defines the relationship between an IP Virtual LAN VLAN and the subnets in the IP network Every IP VLAN interface has one IP VLAN a...

Страница 96: ... the subnet number and the host number Each IP address bit corresponding to a 1 in the subnet mask is in the network subnet part of the address Each IP address bit corresponding to a 0 is in the host part of the IP address Advertisement Address The switching module uses this IP address when it advertises routes to other stations on the same subnet In particular the system uses this address for sen...

Страница 97: ...er the minimum holding time has expired You also need to enter the ATM port number for this interface If you define only PVCs on the interface you need to enter only the PVC numbers and the ATM port number The other prompts do not appear because you do not enter an ATM ARP server address If you define both SVCs and PVCs enter all LIS interface information Displaying Interfaces You can display both...

Страница 98: ... VLAN Index 1 VLAN 158 101 1 1 255 255 255 0 1 Down 2 2 LIS 158 101 112 1 255 255 255 0 1 Up 1 Index Type IP address Subnet mask Cost State Port IP forwarding is enabled RIP is active ICMP discovery is disabled Index Type IP address Subnet mask Cost State VLAN index 1 VLAN 158 101 1 1 255 255 255 0 1 Down 2 Index Type IP address Subnet mask Cost State Port 2 LIS 158 101 112 1 255 255 255 0 1 Up 1 ...

Страница 99: ...ng time and the ATM port associated with the interface You can also accept the defaults for these values For a LIS interface with only PVCs enter the ATM port and the PVCs associated with the interface You can enter up to 51 PVCs for each interface The maximum number on the LANplex system is 64 LIS interface example with both PVCs and SVCs Enter IP address 158 101 1 1 Enter subnet mask 255 255 0 0...

Страница 100: ...cost value of the interface 5 Enter the type of IP interface VLAN 6 Enter the advertisement address for this interface 7 Enter the index of the VLAN associated with the interface Example Enter IP address 158 101 1 1 Enter subnet mask 255 255 0 0 255 255 255 0 Enter cost 1 Enter interface type vlan lis vlan Enter advertisement address es 158 101 1 255 IP VLANs Index Ports 3 1 8 4 9 12 Select VLAN i...

Страница 101: ...o remove an IP interface definition 1 From the top level of the Administration Console enter ip interface remove 2 Enter the index numbers of the interfaces you want to remove If you have defined one or more PVCs on the interface the Administration Console displays a message indicating that the PVCs will be removed with the interface The following is an example of a prompt for interface 2 which ha...

Страница 102: ...ated with the interface To remove an advertisement address 1 From the top level of the Administration Console enter ip interface removeAdvertisement 2 Enter the index interface number and the advertisement address you want to remove Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface route arp atmArpServer multicast udpHelper routing icmpRouterDisc...

Страница 103: ...d hosts You can make static entries in this table using the Administration Console or configure the system to use RIP to exchange routing information automatically Each routing table entry contains the following information Destination IP Address and Subnet Mask These elements define the address of the destination network subnet or host A route matches an IP address if the bits in the IP address t...

Страница 104: ...ddresses match the route s IP address and subnet mask The system forwards such packets to the indicated gateway Status For each interface the route provides the status information in Table 9 1 In addition to the routes to specific destinations the routing table can contain an additional entry called the default route The system uses the default route to forward packets that do not match any other ...

Страница 105: ...t least one IP interface Static routes remain in the table until you remove them or the corresponding interface Static routes take precedence over dynamically learned routes to the same destination Static routes are not included in periodic RIP updates sent by the system To define a static route 1 From the top level of the Administration Console enter ip route static You are prompted for the route...

Страница 106: ...ckets that do not match any other routing table entry A system can learn a default route using RIP or you can configure a default route statically If a system s routing table does not contain a default route either statically configured or learned using RIP then it cannot forward a packet that does not match any other routing table entry If this occurs then the module drops the packet and sends an...

Страница 107: ...x system uses the Address Resolution Protocol ARP to find the MAC addresses corresponding to the IP addresses of hosts and routers on the same subnets An ARP cache is a table of known IP addresses and their corresponding MAC addresses Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface route arp atmArpServer multicast udpHelper routing icmpRouterDi...

Страница 108: ... Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface route arp atmArpServer multicast udpHelper routing icmpRouterDiscovery rip ping statistic s display remove flush IP routing is enabled RIP is active ICMP router discovery is disabled IP address I F Hardware address Circuit 158 101 112 2 1 00 40 0b 40 64 e6 158 101 112 7 1 08 00 20 76 a2 f2 158 101 116 7 2 ...

Страница 109: ...minister the ATM ARP cache Displaying ATM ARP Servers To display a list of ATM ARP servers from the top level of the Administration Console enter ip atmArpServer display Example Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface route arp atmArpServer multicast udpHelper routing icmpRouterDiscovery rip ping statistics display remove flush Top Leve...

Страница 110: ...moving an ATM ARP Server To delete a currently defined ATM ARP server from the top level of the Administration Console enter ip atmArpServer remove The systems prompts you for one or more index numbers associated with the ATM ARP servers that you want to remove The ATM ARP server display shows the index number assigned to each ATM ARP server The system also displays the current index numbers in th...

Страница 111: ...ace route arp atmArpServer multicast udpHelper routing icmpRouterDiscovery rip ping statistics display define remove arp display remove flush IP routing is enabled RIP is active ICMP router discovery is disabled IP address ATM Address Circuit 158 101 112 2 47 005 80 ffe100 0000 f21a 2130 80000212d0f 18 1 32 158 101 112 7 47 005 80 ffe100 0000 f22a 2130 80000211d01 18 1 33 158 101 116 7 47 005 81 f...

Страница 112: ... port you can boot hosts through the router UDP Helper also provides a relay agent for DHCP broadcasts UDP packets that rely on the BOOTP relay agent are modified and then forwarded through the router The following ports for the UDP services are mentioned in this section on UDP Helper BOOTP including DHCP 67 TIME 37 DNS 53 UDP Helper allows you to configure the amount of time a UDP packet is forwa...

Страница 113: ... a Port or an IP Forwarding Address You can remove a port number or IP forwarding address defined for UDP Helper To remove a port number or IP forwarding address 1 From the top level of the Administration Console enter ip udpHelper remove 2 Enter the UDP port number that you want to remove 3 Enter the IP forwarding address that you want to remove The port numbers and IP forwarding addresses you sp...

Страница 114: ...ther hosts When you enable IP routing the switching module acts as a normal IP router forwarding IP packets from one subnet to another when required When you disable IP routing the system discards any IP packets not addressed directly to one of its defined IP interfaces By default IP routing is disabled on the system To enable or disable IP routing 1 From the top level of the Administration Consol...

Страница 115: ...ther you can configure it to work with this protocol To enable ICMP Router Discovery from the top level of the Administration Console enter ip icmpRouterDiscovery Enter the ICMP Router Discovery mode enabled or disabled This protocol is disabled by default Setting the RIP Mode You can select a RIP mode that is appropriate for your network RIP can operate in any of three modes Off The station ignor...

Страница 116: ...achable A network is unreachable when there is no route to that network To ping an IP station 1 From the top level of the Administration Console enter ip ping 2 Enter the IP address of the station you want to ping IP Address 192 9 200 40 You may receive one of the following responses 192 9 200 40 is alive OR no answer from 192 9 200 40 For a remote IP address you can also receive the following res...

Страница 117: ...icmpRouterDiscovery rip ping statistics Table 9 2 IP Statistics Field Description inReceives Total number of IP datagrams received including those with errors forwDatagrams Number of datagrams that the IP station attempted to forward inDelivers Number of datagrams that the IP station delivered to local IP client protocols outRequests Number of datagrams that local IP client protocols passed to IP ...

Страница 118: ...9 24 CHAPTER 9 ADMINISTERING IP ROUTING ...

Страница 119: ...his appendix includes information on how to display or configure the following parameters Enabling and disabling the Distance Vector Multicast Routing Protocol DVMRP Enabling and disabling the Internet Group Membership Protocol IGMP Administering IP multicast interfaces Administering multicast tunnels The Route display The Cache display To use IP multicast routing on the LANplex system you must ha...

Страница 120: ...ing and Disabling IGMP IGMP enables a router or switch to determine whether group members exist in a subnetwork or leaf of the Spanning Tree It uses two search methods to make this determination Query mode The router or switch with the lowest IP address in the LAN broadcasts a query to all other members of the subnetwork to determine whether they are also in the group End stations respond to the q...

Страница 121: ...haracteristics on previously defined IP interfaces A multicast interface has three characteristics explained next DVMRP Metric Value The DVMRP metric value determines the cost of a multicast interface The higher the cost the less likely it is that the packets will be routed over the interface The default value is 1 Time To Live TTL Threshold The TTL threshold determines whether the interface will ...

Страница 122: ...he top level of the Administration Console enter ip multicast interface display 2 Enter the index numbers of the interfaces you want to display Example multicast interface configuration Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface route arp atmArpServer multicast udpHelper routing icmpRouterDiscovery rip ping statistics dvmrp igmp interface ...

Страница 123: ...cast interface enable 2 Enter the index number s of the interface s you want to enable 3 Enter the DVMRP metric value of the chosen interface s 4 Enter the Time To Live TTL threshold of the chosen interface s 5 Enter the rate limit of the chosen interface s Example Enter an IP interface index 1 2 Enter Interface DVMRP metric 1 1 Enter Interface TTL threshold 1 Enter interface rate limit in KBits s...

Страница 124: ...re a tunnel The only configurations that require a tunnel are those that require a connection between two multicast internetworks through one or more unicast routers Displaying Multicast Tunnels To display the IP multicast tunnel s on the router from the top level menu of the Administration Console enter ip multicast tunnel display Example IP multicast tunnel configuration Top Level Menu system et...

Страница 125: ... 40 Enter tunnel DVMRP metric 1 1 Enter tunnel TTL threshold 1 Enter tunnel rate limit 0 Removing a Multicast Tunnel To remove an IP multicast tunnel 1 From the top level of the Administration Console enter ip multicast tunnel remove 2 Enter the index number s of the interfaces associated with the tunnel you want to remove Example Enter an IP interface index 1 2 The tunnel is removed Top Level Men...

Страница 126: ...cheDisplay Multicast Routing Table 2598 entries Origin Subnet From Gateway Metric Tmr In If Out Ifs 157 88 29 1 32 137 39 229 98 18 25 T1 I1 137 39 2 254 32 137 39 229 98 5 25 T1 I1 131 215 125 236 32 137 39 229 98 14 25 T1 I1 130 118 106 254 32 137 39 229 98 10 25 T1 I1 129 127 118 12 32 137 39 229 98 10 25 T1 I1 129 127 110 12 32 137 39 229 98 10 25 T1 I1 129 127 110 11 32 137 39 229 98 13 25 T1...

Страница 127: ...splay Field Description Origin Subnet The source address and the number of bits in the subnetwork From Gateway The interface address of the gateway Metric The hop count Tmr The amount of time in seconds since the routing table entry was last reset In If1 Interface number on which that gateway is connected Traffic is expected to originate on this interface T represents the tunnel P denotes that a p...

Страница 128: ...33 packets 128 138 213 24 224 2 0 1 3m 2h 2m T1P I1p 128 138 213 1 23 packets 128 206 212 24 224 2 0 1 92s 36m 60s T1P I1p 128 206 212 69 8 packets 131 136 234 24 224 2 0 1 3m 57m 3m T1P I1p 131 136 234 103 12 packets 138 39 25 24 224 2 0 1 103s 4h 71s T1P I1p 138 39 25 48 46 packets 192 5 28 24 224 2 0 1 80s 2h 48s T1P I1p 192 5 28 43 178 packets 199 94 220 24 224 2 0 1 104s 1h 72s T1P I1p 199 94...

Страница 129: ...icast group CTmr Cache timer The amount of time in seconds s minutes m and hours h that a cache entry has to remain in the cache Age Number of seconds s minutes m or hours h that the cache entry has existed PTmr The time remaining in seconds s minutes m or hours h before another prune will be sent to prune the Spanning Tree In If Interface number on which that gateway is connected Traffic is expec...

Страница 130: ...10 12 CHAPTER 10 ADMINISTERING IP MULTICAST ROUTING ...

Страница 131: ...xchange IPX protocol to route packets For more information about how IPX works see Part III of this Guide You can display and configure the following on your LANplex system IPX interfaces Routes Servers IPX forwarding Routing Information Protocol RIP Enhanced RIP mode Service Advertising Protocol SAP IPX statistics ...

Страница 132: ...r redundant paths you should assign a cost of 1 to each interface Encapsulation format IPX routing uses four Ethernet encapsulation formats and two FDDI encapsulation formats The Ethernet encapsulation formats are Ethernet Type II Novell 802 3 raw 802 2 LLC and 802 3 SNAP The FDDI encapsulation formats are FDDI 802 2 and FDDI SNAP The two FDDI encapsulation formats correspond to the Ethernet 802 2...

Страница 133: ...rface 1 From the Administration Console top level menu enter ipx interface define You are prompted for the interface s parameters To use the value in brackets press Return at the prompt 2 Enter the IPX network address of the interface 3 Enter the cost of the interface 4 Enter the format of the interface 5 Enter the index of the IPX VLAN associated with this interface Top Level Menu system ethernet...

Страница 134: ...ports associated with the interface To remove an IPX interface definition 1 From the Administration Console top level menu enter ipx interface remove 2 Enter the index number s of the interface s you want to remove The interface is removed Enter IPX Address 0x45469f30 Enter Cost 1 1 Enter Frame Format Ethernet II 0 802 2 1 Raw 802 3 2 SNAP 3 1 IPX VLANs Index Ports 3 1 8 4 9 12 Select VLAN index 3...

Страница 135: ...y known to the router Hops The number of routers that must be crossed to reach the network segment The maximum number of routers a packet can cross is 15 Exception An IPX NetBIOS packet can cross no more than 7 routers Tics An estimate of how long it will take the packet to reach this segment A tic is approximately 55 milliseconds Node The 6 byte address of the router that can forward packets to t...

Страница 136: ...ake precedence over dynamically learned routes to the same destination You can set up to 16 static routes To define a static route 1 From the Administration Console top level menu enter ipx route static 2 Enter the 4 byte IPX network address of the route 3 Enter the cost of the route 4 Enter the interface number of the route Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp anal...

Страница 137: ... learned routes from the Administration Console top level menu enter ipx route flush All learned routes are immediately deleted from the routing table Enter IPX address 0x45469f30 Enter Cost 1 Enter Interface number 1 Enter node address 08 00 3e 22 15 78 Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface route server forwarding rip enhanced sap st...

Страница 138: ... Console Each server table contains the following information Name The user defined name of the server Type The type of service provided by the server Node The 6 byte address of the server that can forward packets to the segment Socket The 2 byte socket address on which the server will receive service requests Hop The number of networks that must be crossed to reach the server The maximum number i...

Страница 139: ...ine a static server 1 From the Administration Console top level menu enter ipx server static 2 Enter the interface number of the server 3 Enter the service type of the server 4 Enter the service name of the server 5 Enter the IPX network address of the server 6 Enter the socket value of the server 7 Enter the node address of the server Top Level Menu system ethernet fddi atm bridge ip ipx appletal...

Страница 140: ...e Administration Console top level menu enter ipx server flush All learned servers are immediately deleted from the server table Enter Interface number 1 Enter service type 4 Enter service name gb201 Enter IPX address 0x8c14a238 Enter socket 0x8059 Enter node address 00 00 2e f3 56 01 Enter hops 2 Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface...

Страница 141: ... 2 Enter the IPX forwarding state enabled or disabled To use the value in brackets press Return at the prompt Setting the RIP Mode You can select a RIP mode that is appropriate for your network RIP can operate in any of three modes Off The system ignores all incoming RIP packets and does not generate any RIP packets of its own Passive The system processes all incoming RIP packets but does not broa...

Страница 142: ... mode allows the system greater interoperability with routers that do not explicitly follow the IPX router implementation guidelines Enhanced RIP default By default enhanced RIP is disabled To enable or disable enhanced RIP mode 1 From the Administration Console top level menu enter ipx enhanced 2 Enter the enhanced RIP state enabled or disabled To use the value in brackets press Return at the pro...

Страница 143: ...respond to SAP requests Active The system processes all incoming SAP packets responds to explicit requests for routing information and broadcasts periodic and triggered SAP updates SAP default mode By default SAP is off To set the SAP operating mode 1 From the Administration Console top level menu enter ipx sap 2 Enter the SAP mode off passive or active To use the value in brackets press Return at...

Страница 144: ...mmary statistics Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface route server forwarding rip enhanced sap statistics summary rip sap forwarding IPX forwarding is enabled RIP is active SAP is active Received Transmitted Dropped Msg Pool Empty 1170878 565099 0 0 Table 11 1 IPX Summary Statistics Field Description Received Number of IPX packets re...

Страница 145: ...ics summary rip sap forwarding IPX forwarding is enabled RIP is active SAP is active RIP Received RIP Transmitted RIP dropped 106195 7929 0 RIP Responses RIP Requests RIP Entries 100552 5643 2 Table 11 2 IPX RIP Statistics Field Description RIP Received Number of IPX RIP packets received RIP Transmitted Number of IPX RIP packets transmitted RIP Dropped Number of IPX RIP packets dropped RIP Respons...

Страница 146: ...AP Transmitted SAP dropped 1064015 22493 0 SAP Responses SAP Requests SAP Entries 1063532 45 0 SAP GNS Responses SAP GNS Requests 0 438 Table 11 3 IPX SAP Statistics Field Description SAP Received Number of IPX SAP packets received SAP Transmitted Number of IPX SAP packets transmitted SAP Dropped Number of IPX SAP packets dropped SAP Responses Number of IPX SAP Responses that have been processed S...

Страница 147: ...Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface route server forwarding rip enhanced sap statistics summary rip sap forwarding IPX forwarding is enabled RIP is active SAP is active Received Transmitted Forwarded 1335653 565105 0 Hdr Errors Hop Count Errors Addr Errors 13758 0 13758 No Routes Misc Errors 2 411 NetBIOS Rx NetBIOS Tx NetBIOS Max Hops ...

Страница 148: ... maximum transport control Addr Errors Number of IPX packet dropped due to IPX Address errors in network layer header No Routes Number of IPX packets dropped because the IPX route is unknown Misc Errors Number of multicasts attempted to be forwarded NetBIOS Rx Number of IPX NetBIOS packets received NetBIOS Tx Number of IPX NetBIOS packets transmitted NetBIOS Max Hops Number of IPX NetBIOS packets ...

Страница 149: ...e the AppleTalk protocol to route packets For more information on how AppleTalk routing works see Chapter 7 Routing with AppleTalk You can display and configure the following AppleTalk interfaces Routes AARP cache Zones AppleTalk forwarding Checksum generation and verification AppleTalk statistics ...

Страница 150: ...on seed interfaces wait and listen for a seed interface and then take this configuration initialization information from the first seed interface they detect After the non seed interface obtains a network configuration it begins to participate in the routing of the network Network Range A range of numbers used to designate a network segment s identity This element allows the physical segment betwe...

Страница 151: ... parameters To use the value in brackets press Return at the prompt The following message appears Configure seed interface n y y 2 Enter n no or y yes 3 Enter the start of the network range associated with the interface 4 Enter the end of the network range associated with the interface 5 Enter the default zone name The default zone name is used by clients that have not been configured to use a par...

Страница 152: ... remove an AppleTalk interface 1 At the Administration Console s top level menu enter appletalk interface remove 2 Enter the index number s of the interface s you want to remove The interface is no longer defined on the router Enter Start of Network Range 10000 Enter End of Network Range 10100 Enter Default Zone engineering Enter Zone Name q Appletalk VLANs Index Ports 3 1 8 4 9 12 Select VLAN ind...

Страница 153: ...k Range A range of numbers used to designate a network segment s identity Distance The distance in hops to the destination network Interface The defined interface number State The status good suspect bad or really bad of each route Displaying the Routing Table You can display the routing tables for the system to determine which routes are configured and if they are operational To display the conte...

Страница 154: ... 1 10 1 good 3 4 1 good 10 14 6 1 good 15 19 7 1 good 61 6 1 good 100 100 10 1 good 201 300 7 1 good 2010 2015 2 1 good 10009 10009 5 1 good 10010 10010 7 1 good 10060 10060 8 1 good 10110 10113 5 1 good 10116 10117 5 1 good 10118 10118 6 1 good 10119 10119 4 1 good 10120 10120 7 1 good 10122 10122 9 1 good 10310 10329 10 1 good 10410 10410 8 1 good 11010 11019 9 1 good Top Level Menu system ether...

Страница 155: ...e AMT AARP sends a request to the desired protocol address and the hardware address is added to the table when the destination node replies AARP is also responsible for registering a node s dynamically assigned address on the network This process is described below AARP randomly assigns an address AARP broadcasts AARP probe packets to this address to determine if another node is already using the ...

Страница 156: ... 89 01 8b 51 1 18 20112 1 08 00 02 04 80 b6 1 31 20125 193 08 00 07 d7 69 1f 3 388 20125 76 08 00 07 66 62 9d 3 862 20125 67 08 00 07 ee 10 a2 3 851 20124 41 08 00 07 7c c3 d8 2 864 20112 225 00 20 af 0b d8 f1 1 270 20112 135 00 20 af 9e 68 62 1 174 20112 147 00 00 94 41 de 79 1 26 20112 132 08 00 09 7f 98 c5 1 24 20112 112 08 00 07 7c 20 61 1 121 20112 148 08 00 07 ac 56 4b 1 1098 20112 244 00 20...

Страница 157: ...s To flush all AARP cache entries 1 At the Administration Console s top level menu enter appletalk aarp flush Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface route aarp zone forwarding checksum ping statistics display remove flush Top Level Menu system ethernet fddi atm bridge ip ipx appletalk snmp analyzer script logout interface route aarp zo...

Страница 158: ...ates and maintains a Zone Information Table ZIT in each router The entries in this table match the network numbers with the zone names In the Administration Console you can display the zone table either by network numbers or by zones To display the zone table From the Administration Console top level menu enter appletalk zone display network OR appletalk zone display zone Top Level Menu system eth...

Страница 159: ...15 Zone Manchester UK is assigned to 1 network 10310 10329 Zone DC8 is assigned to 1 network 30110 30129 Zone Chicago is assigned to 1 network 22030 22030 Zone Startek Enet1 is assigned to 1 network 20033 20033 Zone Startek TR1 is assigned to 1 network 20037 20037 Zone Test GmbH is assigned to 1 network 12010 12012 Zone Madrid3Com is assigned to 1 network 14010 14029 Zone NSDEng is assigned to 1 n...

Страница 160: ...ation prompt Pinging an AppleTalk Node The AppleTalk Echo Protocol AEP sends a datagram an Echo Request from one node to another which causes the destination node to return or echo the datagram an Echo Reply to the sender This allows you to determine whether a node is accessible before any sessions are started To ping an AppleTalk node 1 At the Administration Console s top level menu enter appleta...

Страница 161: ...k snmp analyzer script logout interface route aarp zone forwarding checksum ping statistics ddp rtmp zip nbp DDP forwarding is enabled inReceives inForwards inLocals inNoRoutes 131131 113171 17906 22 inNoClients inTooShorts inTooLongs inShortDdps 0 0 0 0 inCsumErrors inBcastErrors inTooFars inDiscards 0 0 0 54 outLocals 15600 Table 12 1 AppleTalk Statistics Field Description inReceives Total numbe...

Страница 162: ...their type was short DDP inCsumErrors Number of DDP datagrams which were dropped because of a checksum error inBcastErrors Number of DDP datagrams for which this DDP entity was their final destination and which were dropped because of a broadcast error inTooFars Number of input datagrams dropped because this entity was not their final destination and their hop count would exceed 15 inDiscards Numb...

Страница 163: ...particular network routeLessChgs Number of times RTMP changes the Next Internet Router in a routing entry because the hop count advertised in a routing table was less than the current hop count for a particular network routeDeletes Number of times RTMP deletes a route because it was aged out of the table routeOverflows Number of times RTMP attempted to add a route to the RTMP table but failed due ...

Страница 164: ...f ZIP GetNetInfo request packets received inGniReplies Number of ZIP GetNetInfo reply packets received inLocalZones Number of Zip GetLocalZones requests packets received inZoneLists Number of Zip GetZoneLists requests packets received inObsoletes Number of ZIP Takedown or ZIP Bringup packets received inZoneCons Number of times a conflict has been detected between this entity s zone information and...

Страница 165: ...oneInvs Number of times this entity has sent a ZIP GetNetInfo reply with the zone invalid bit set in response to a GetNetInfo request with an invalid zone name outAddrInvs Number of times this entity had to broadcast a ZIP GetNetInfo reply because the GetNetInfo request had an invalid address Table 12 3 ZIP Statistics continued Field Description Top Level Menu system ethernet fddi atm bridge ip ip...

Страница 166: ... NBP Statistics Field Description inLkupReqs Number of NBP Lookup Requests received inBcastsReqs Number of NBP Broadcast Requests received inFwdReqs Number of NBP Forward Requests received inLkupReplies Number of NBP Lookup Replies received inErrors Number of NBP packets received that were rejected for any error ...

Страница 167: ...V Chapter 13 Remote Monitoring RMON Technology REMOTE MONITORING RMON AND THE LANPLEX SYSTEM ...

Страница 168: ...ding historical data in its local memory The Management Console Communicates with the probe and collects the summarized data from it The console does not need to reside on the same network as the probe and can manage the probe through SNMP The RMON specification consists almost entirely of the definition of the MIB The RMON MIB contains standard MIB variables defined to collect comprehensive netwo...

Страница 169: ... RMON MIB reports by exception rather than by sending constant or frequent information to the network management console The RMON probe informs the network management console directly if the network enters an abnormal state The console can then use more information from the probe such as history information to diagnose the abnormal condition LANplex RMON Implementation The LANplex Extended Switchi...

Страница 170: ... and then takes action based on these statistics For example the system can generate a log event and send an RMON trap if errors on a port exceed a user set threshold You must assign an IP address to the LANplex system to manage RMON See the LANplex 2500 Administration Console User Guide for information on how to assign an IP address Figure 13 1 shows an example of a LANplex RMON implementation Th...

Страница 171: ... network device without a specific description of that device 3Com ships SNMP MIB files with LANplex Extended Switching System software as ASN 1 files MIB Objects The data in the MIB consists of objects that represent features of the equipment that an agent can control and manage Examples of objects in the MIB include a port that you can enable or disable and a counter that you can read A counter ...

Страница 172: ...s not appear in the display You do not need to know the contents of every MIB object to manage a network Most network management applications including Transcend Enterprise Manager Software make the MIB transparent However knowing how different management features are derived from the MIB allows you to better understand how to use the information that they provide etherStatsPkts OBJECT TYPE SYNTAX...

Страница 173: ...give you misleading results Counters are not infinite which makes rate comparisons an efficient way to use them When counters reach a predetermined limit they return to 0 roll over A single low counter value might accurately represent a condition on the network It might simply indicate that a roll over has occurred When you disable a port the application might not update some of the statistics cou...

Страница 174: ...itors the counters and thresholds continually during normal operations to provide data for later calibration Example of an Alarm Threshold Figure 13 3 shows a counter with thresholds set manually Figure 13 3 Manually Set Thresholds You can associate an alarm with the high threshold the low threshold or both The actions taken because of an alarm depend on the network management application Time Cou...

Страница 175: ... An alarm does not occur if the value has not fallen below the low threshold before rising above the high threshold The counter value exceeds the low threshold after previously exceeding the high threshold An alarm does not occur if the value has not risen above the high threshold before falling below the low threshold In Figure 13 3 for example an alarm occurs the first time the counter exceeds t...

Страница 176: ...VI Appendix A Technical Support APPENDIX ...

Страница 177: ... as well as technical articles This service is available via analog modem or ISDN 24 hours a day seven days a week Access by Analog Modem To reach the service by modem set your modem to 8 data bits no parity and 1 stop bit Call the telephone number nearest you Country Data Rate Telephone Number Australia up to 14400 bps 61 2 9955 2073 France up to 14400 bps 33 1 69 86 69 54 Germany up to 9600 bps ...

Страница 178: ...w 3Com com This service features news and information about 3Com products customer service and support 3Com s latest news releases selected articles from 3TECH journal 3Com s award winning technical journal and more 3ComForum on CompuServe 3ComForum is a CompuServe service containing patches software drivers and technical articles about all 3Com products as well as a messaging section for peer sup...

Страница 179: ...k planning installation hardware maintenance application training and support services When you contact your network supplier for assistance have the following information ready Diagnostic error messages A list of system hardware and software including revision levels Details about recent configuration changes if applicable If you are unable to contact your network supplier see the following secti...

Страница 180: ...d to the sender unopened at the sender s expense To obtain an RMA number call or fax 10 22 96 Country Telephone Number Country Telephone Number Australia 1800 678 515 Japan 81 3 3345 7251 Mexico 525 531 0591 Belgium 0800 71429 Netherlands 06 0227788 Brazil 55 11 546 0869 Norway 800 11376 Canada 416 498 3266 Singapore 65 538 9368 Denmark 800 17309 South Africa 27 11 803 7404 Finland 0800 113153 Spa...

Страница 181: ...in menu 1 6 name binding protocol NBP 7 9 network layer 7 6 nodes 7 2 physical layer 7 5 printer access protocol PAP 7 10 protocols about 7 1 protocols and OSI levels 7 4 routing table maintenance protocol RTMP 7 6 routing tables 7 8 session layer protocol ASP 7 10 statistics viewing 12 13 transaction protocol ATP 7 9 zone information protocol ZIP 7 9 zones 7 3 AppleTalk networks 7 2 extended 7 2 ...

Страница 182: ...extended switching overview 1 1 F fax service See 3ComFacts flushing ARP cache 9 15 learned routes AppleTalk 12 6 learned routes IP 9 12 learned routes IPX 11 7 for 11 9 forwarding configuring AppleTalk 12 11 G gateway routing table and the 4 5 See also router H hysteresis mechanism 13 8 I ICMP defined 4 9 echo request and reply 9 22 echo Reply 4 9 echo request 4 9 ping and 9 22 Redirect 4 9 Time ...

Страница 183: ...ast routing about 5 1 algorithms 5 3 interfaces 10 1 administering 10 3 defining 10 2 displaying 10 4 enabling 10 5 MBONE 5 2 rate limit 5 6 10 4 TTL threshold 10 3 tunnels 5 6 10 6 IP route default 9 10 9 13 defining static 9 11 removing from table 9 12 status 9 10 IP router transmission process 4 2 IP routing address classes 4 3 basic elements 4 2 enabling 9 20 ICMP 4 9 OSI reference model 4 1 r...

Страница 184: ... AppleTalk 7 6 network numbers extended 7 2 nonextended 7 2 network supplier support A 3 nodes AppleTalk 7 2 nonextended network numbers 7 2 O on line technical services A 1 OSI Reference Model AppleTalk routing and 7 5 IP routing and 4 1 IPX routing and 6 2 P PAP 7 10 physical layer AppleTalk 7 5 pinging AppleTalk node 12 12 IP station 9 22 port See also FDDI port printer access protocol 7 10 pro...

Страница 185: ...oute 9 12 static routes 4 6 routing table IPX contents 6 8 described 6 8 displaying 11 6 dynamic routes 6 9 example 6 9 flushing learned routes 11 7 removing a route 11 7 static routes 6 9 RTMP description of 7 6 S SAP aging mechanism 6 14 packet structure 6 11 request handling 6 15 using for dynamic routes 6 14 SAP mode setting 11 13 SAP statistics displaying 11 16 seed routers 7 4 segmentation i...

Страница 186: ...8 3 displaying 8 1 modifying 8 4 removing 8 5 VLAN interfaces about 9 1 characteristics of 9 2 defining 9 6 VLANs application oriented 2 2 MAC address group 2 2 overlapped IP 2 7 port group 2 1 protocol sensitive 2 2 routing between 2 8 Z ZIP 7 9 statistics displaying 12 15 zone information protocol ZIP 7 9 zone information table ZIT 7 9 displaying the 12 10 zone AppleTalk default 12 3 example of ...

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