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Equalizer Installation and Administration Guide 

129

 

Index

A
accessing the administration interface

  35

active

connections

  40, 41, 43, 66

requests

  47

active content verification see ACV.
ACV

  72

probe string

  63

response string

  63

adaptive load balancing

  2, 64, 66, 76, 88, 90

add menu

  36

Add Site dialog

  90

adding

a geographic cluster

  87

a server to a cluster

  75

a server to a match rule

  83

a site to a geographic cluster

  90

a virtual cluster

  62

address

administration

  10

cluster

  62

resource

  91

server

  76

adjusting

a server’s static weight

  76

a site’s static weight

  92

administration

address

  10

interface

  10, 34

accessing

  35

changing the password

  27

password

  57

agent

custom

  100

Equalizer

  8

IP address

  91

server

  44, 68

site

  48, 49

aggressive load balancing

  67

algorithm

  65

always use cookie

  64

authoritative name server

  7

configuring

  86

average triangulation time

  49

B
backup

  13

mode

  14

server

  76

unit

  13, 51

browser preferences

  35

C
change configuration

  51, 55, 56

changing

a server’s static weight

  76

a site’s static weight

  92

the administration password

  27, 57

the console password

  27

checklist, configuration

  31

client request packets

  10

cluster

adding

  62

adding a server to

  75

address

  62

deleting

  75

geographic

  6

heterogeneous

  78

homogenous

  77

information, displaying

  40

port

  63

statistics, plotting

  41

summary

  39

virtual

  11

Cluster Parameters page

  40

Cluster Summary

  39

committing changes to the configuration parameters

  

26

comparison operator

  79, 81

computed load

  41, 44

configuration

  24

backup

  13

checklist

  31

cluster

  40

examples

  16

failover

  29, 51

network

  75

network parameters

  25

parameters, committing changes to

  26

Summary of Contents for Equalizer

Page 1: ...Equalizer Installation and Administration Guide Version 7 0 September 2003 Coyote Point Systems Inc 12 South First Street Suite 616 San Jose California 95113 ...

Page 2: ......

Page 3: ...r respective companies or organizations THE SPECIFICATIONS AND INFORMATION REGARDING THE PRODUCTS IN THIS MANUAL ARE SUBJECT TO CHANGE WITHOUT NOTICE ALL STATEMENTS INFORMATION AND RECOMMENDATIONS IN THIS MANUAL ARE BELIEVED TO BE ACCURATE BUT ARE PRESENTED WITHOUT WARRANTY OF ANY KIND EXPRESS OR IMPLIED USERS MUST TAKE FULL RESPONSIBILITY FOR THEIR APPLICATION OF ANY PRODUCTS See Appendix F for c...

Page 4: ...iv Coyote Point Systems Inc ...

Page 5: ... Single Network Environment 12 Using a Second Equalizer as a Backup Unit 13 Using Reserved IP Addresses 14 Equalizer Configuration Worksheet 16 Configuration Worksheet for Using Reserved IP Addresses 18 2 Installing Equalizer 19 Installing Equalizer 20 Setting up a Terminal or Terminal Emulator for Equalizer 21 3 Configuring Equalizer 23 Equalizer Configuration 24 Configuring the Network Parameter...

Page 6: ... Through the Interface 36 Monitoring Equalizer Operation 37 Displaying Equalizer Information 38 Displaying the Cluster Summary 39 Displaying the System Event Log 40 Displaying Cluster Information 40 Plotting Cluster Performance 41 Displaying Server Information 42 Plotting Server Performance 43 Displaying Geographic Cluster Information 45 Plotting Geographic Cluster Performance 46 Displaying Site I...

Page 7: ...h Servers 75 Adding a Server to a Cluster 75 Adjusting a Server s Static Weight 76 Shutting Down a Server Gracefully 78 Deleting a Server 79 Specifying Layer 7 Rules 79 Defining a Match Rule 80 Modifying a Match Rule 82 Removing a Match Rule 83 Adding a Server to a Match Rule 83 Removing a Server from a Match Rule 84 6 Administering Geographic Clusters 85 Geographic Load Balancing with Envoy 86 En...

Page 8: ...when trying to connect via FTP to an FTP cluster 97 A Using Server Agents 99 Introducing Server Agents 100 Custom Server Agents 100 B Using Reserved IP Addresses 101 Reserved IP Addresses 102 Configuration Worksheet for Using Reserved IP Addresses 103 C Regular Expression Format 105 D Equalizer Configuration File 109 Modifying the Equalizer Configuration File 110 Equalizer Parameters 111 Cluster S...

Page 9: ...d shutting down servers Administering Geographic Clusters adding and removing geographic clusters and sites and changing geographic load balancing and targeting options Troubleshooting diagnosing Equalizer installation and configuration problems Appendix A describes how to develop custom Server Agents Appendix B describes how to configure Equalizer to distribute requests to servers assigned IP add...

Page 10: ...es keywords and syntax from text Checklists are used to review steps that you must complete before proceeding to the next task Checkmarks are used to identify items that you should verify or procedures you should try to resolve particular problems Information critical to Equalizer operation is highlighted with an attention icon Note Notes are used to highlight important information and special con...

Page 11: ...lizer Installation and Administration Guide 1 1 Overview Introducing Equalizer 2 Layer 7 Load Balancing 5 Geographic Load Balancing 6 Equalizer Network Configurations 10 Equalizer Configuration Worksheet 16 ...

Page 12: ... header of the request packet and forwards the modified packet to the selected server To determine which server to route a request to Equalizer uses intelligent load balancing algorithms that take into account the configuration options set for the cluster and servers real time server status information as well as information from the request itself Network Address Translation Equalizer s Network A...

Page 13: ...will not route new requests to servers in this state Real Time Server Status Information Equalizer can gather real time information about a server s status using Server Agents and Active Content Verification Server Agents can be installed on each server that provide Equalizer with real time performance statistics This enables Equalizer to adjust the dynamic weights of the servers in a cluster acco...

Page 14: ...fication is not supported for UDP clusters Maintaining Persistent Sessions Maintaining persistent sessions is useful when state information is shared between the client and server For example when using the SSL protocol the client and server perform an expensive session establishment procedure that must be repeated whenever the client connects to a new server Maintaining persistent sessions minimi...

Page 15: ...ion is to a different virtual cluster When inter cluster stickiness is enabled for a cluster Equalizer checks the cluster for a sticky record as each connection request is received just like it does for ordinary sticky connections If no sticky record is found Equalizer proceeds to check all of the other clusters that have the same IP address If a sticky record is found the user is connected to the...

Page 16: ...nable requests to be automatically distributed across servers in different physical locations This can dramatically improve reliability by ensuring that your service remains available even if a site wide failure occurs Equalizer can also improve performance by routing requests to the location with the least network latency An Equalizer site is a cluster of servers under Equalizer control A geograp...

Page 17: ...ddresses used to identify hosts on the Internet The authoritative name server for the domain is configured to query the Equalizers in the geographic cluster to resolve the domain name When Equalizer receives a resolution request it uses the load balancing algorithms configured for the geographic cluster to determine which site is best able to process the request and then returns the address of the...

Page 18: ... 2 Once the geographic cluster has been identified Equalizer sends geographic query protocol probes to the agents running at each site in the cluster Step 1 in Figure 4 These probes contain information about the client that made the request and the resource that is being resolved The site handling the resolution request site 2 in Figure 4 also queries its local agent 3 When an agent receives a pro...

Page 19: ...e 4 Resolving name resolution requests 4 The server uses the information gathered from each site to determine which site is best able to process the request for the client and then forwards the request to that site Figure 5 Figure 5 Selecting a site to process the connection request ...

Page 20: ...s and ports Equalizer s NAT subsystem translates client request packets and then forwards them to the selected server When a server machine sends a response packet back to a client it is processed by Equalizer and then forwarded to the appropriate client across the external network To ensure that Equalizer can process outbound packets the servers routing tables must be configured so that Equalizer...

Page 21: ...85 5 80 Server 199 146 90 10 80 Server 199 146 90 11 80 Cluster 199 146 85 6 80 Server 199 146 90 12 80 Server 199 146 90 13 80 Although four different servers are specified using IP address aliasing enables you to implement this configuration with just two physical servers For example IP addresses 199 146 90 10 and 199 146 90 12 might be configured as aliases on one machine and IP addresses 199 1...

Page 22: ...ration in detail In a single network configuration Equalizer s external interface port is connected to the network and the internal interface port is not used Servers should have valid network addresses on the external network and must be configured to use Equalizer s external address as the gateway for outbound packets It is not necessary to configure an IP address on the internal interface when ...

Page 23: ...s the IP addresses clusters owned by the primary and begins servicing connections In a failover configuration the servers in a virtual cluster use a separate failover gateway address as their default gateway rather than using the IP address of the internal or external interface on a particular Equalizer as their gateway The failover gateway address migrates between the primary and backup unit as n...

Page 24: ...s their default gateway In a hot backup environment the gateway address can migrate between the primary and backup unit so an additional address is required 3 The Equalizer kernel moves out of BACKUP mode into PRIMARY mode When an Equalizer is in PRIMARY mode it performs gateway routing of packets between its internal and external interfaces as well as address translation and load balancing When a...

Page 25: ...slates connections originating from the servers on the reserved network so that external hosts won t see packets originating from non routable addresses If you re using a Failover configuration outbound NAT must be enabled on both Equalizers For more information see Setting up a Failover Configuration on page 51 Note Due to the additional overhead introduced by enabling outbound NAT using reserved...

Page 26: ...twork For the class C network 199 146 85 0 with a default netmask of 255 255 255 0 the external network would be 199 146 85 0 See Figure 8 on page 13 Example 2 Two Class C Networks If you use two class C networks as shown in Figure 7 199 146 85 0 and 199 145 90 0 and choose the first as the external network the external network would be 199 146 85 0 with a netmask of 255 255 255 0 3 What is Equali...

Page 27: ...achines All server IP addresses and aliases must be unique a particular server IP address or alias can be configured on one and only one server machine 7 What virtual cluster addresses will you be configuring The virtual cluster addresses will be addresses on the external network For example 199 146 85 4 HTTP is a virtual cluster on port 80 and 199 146 85 4 FTP is a virtual cluster on port 21 8 Wh...

Page 28: ...ound NAT using reserved internal networks should be approached with caution For more information about using reserved IP addresses see Appendix B 1 What is the reserved network to be used for the internal network Equalizer uses this set of address to balance the load across the servers Equalizer uses the internal network to forward connections to the HTTP daemons running on the servers Example 10 ...

Page 29: ...Equalizer Installation and Administration Guide 19 2 Installing Equalizer Installing Equalizer 20 Setting up a Terminal or Terminal Emulator for Equalizer 21 ...

Page 30: ...pin serial port labeled Serial on the front panel of the Equalizer using the supplied serial cable Figure 10 Equalizer Front Panel 4 Connect Equalizer to the external network Locate the RJ 45 network connector marked Ext on the front panel of the Equalizer Connect this port to the hub or switch that services the external network with a quality category 5 network cable 5 Connect Equalizer to the in...

Page 31: ...ation software If your terminal software supports it set it to ignore hang ups on the serial line This allows a single terminal session to continue running even if Equalizer restarts Configuring HyperTerminal If you are using the Windows HyperTerminal accessory to configure the terminal emulation settings 1 Choose Properties from the File menu 2 Click the Settings tab 3 Enable the Terminal keys ra...

Page 32: ...Chapter 2 Installing Equalizer 22 Equalizer Installation and Administration Guide ...

Page 33: ...inistration Guide 23 3 Configuring Equalizer Equalizer Configuration 24 Geographic Load Balancing Configuration 28 Server Configuration 29 Failover Configuration 30 Testing Your Configuration 30 Equalizer Configuration Checklist 31 ...

Page 34: ...2 on page 24 press ESC and make sure that your terminal emulator is set for VT100 emulation Figure 12 Equalizer Configuration Utility Main Menu 4 Use the Equalizer Configuration Utility to specify Hostname the DNS hostname that is assigned to Equalizer optional Network Interfaces FXP0 and FXP1 the IP addresses of Equalizer on the external and internal networks and the netmasks associated with thes...

Page 35: ...w shown in Figure 14 Figure 14 Equalizer Configuration Utility Network Configuration 3 In the Host field enter the fully qualified name for the Equalizer on your network For example Equalizer mynet com Use the Tab key to move between fields in this dialog Configure network interfaces Configure each of the network interfaces listed below Assign an IP address on the external network to the external ...

Page 36: ... highlight OK and press ENTER 8 To specify the internal interface parameters select fxp1 and press ENTER 9 Specify the IP address and netmask for fxp1 For example if the internal interface will have the address 192 22 34 2 enter 192 22 34 2 in the IPAddress field Enter the NETMASK specified in the configuration worksheet 10 Use the Tab key to highlight OK and press ENTER 11 Use the Tab key to high...

Page 37: ...tely Changing the Administration Interface Password The administration interface password is the edit mode password for the html based administration interface To change the administration password 1 In the Equalizer Configuration Menu window select option 6 Password and press ENTER 2 Type the new password When prompted enter the password again to confirm the change The new password takes effect i...

Page 38: ...ration changes To shut down 1 In the Equalizer Configuration Menu window select option 9 Shutdown and press ENTER 2 When the shutdown process completes it s safe to power off the system Geographic Load Balancing Configuration If you are configuring Equalizer to use Envoy for geographic load balancing you also need to configure your authoritative name server to delegate authority to the Envoy sites...

Page 39: ...ffic on this port to flow freely between an Equalizer server and any Internet clients so that clients trying to resolve hostnames via the Equalizer DNS server can exchange packets with Equalizer sites Equalizer sites can send ICMP echo request packets out through the firewall and receive ICMP echo response packets from clients outside the firewall When a client attempts a DNS resolution Equalizer ...

Page 40: ...iguration a test machine on the external network A client machine somewhere on the Internet to simulate a real world client This machine should be set up so that the only way it can communicate with your servers or Equalizer is through your Internet router 1 From the internal network test machine ping the physical IP address of each server You should be able to successfully ping all of the servers...

Page 41: ...e Internet client test machine connect to each virtual cluster If you need assistance resolving configuration problems see Chapter 7 Troubleshooting Equalizer Configuration Checklist Use this checklist to verify that you ve completed the configuration process Is Equalizer configured Make sure you have set Equalizer s administration address default gateway and network IP addresses If you are using ...

Page 42: ...Chapter 3 Configuring Equalizer 32 Equalizer Installation and Administration Guide ...

Page 43: ...ion Guide 33 4 Administering Equalizer Operation Introducing the Equalizer Administration Interface 34 Accessing the Administration Interface 35 Monitoring Equalizer Operation 37 Configuring Equalizer Operation 50 Shutting Down Equalizer 59 ...

Page 44: ...ative tasks Figure 18 Equalizer Administration Interface You can access the administration interface from a Javascript enabled web browser to Monitor the status of Equalizer and the configured clusters and servers View cluster and server performance statistics graphically Add virtual clusters Modify cluster parameters Delete clusters Add servers to a cluster Adjust server static weights Delete ser...

Page 45: ...iew all of the Equalizer configuration and status information and modify the configuration Logging In To access the administration interface and log into Equalizer 1 Launch a Javascript enabled web browser such as Netscape Navigator 4 or Microsoft Internet Explorer 5 0 2 From the browser load the URL that corresponds to Equalizer s external address For example if the external address is 199 146 85...

Page 46: ...ns commands for shutting down the Equalizer logging out of the Administration Interface and modifying Equalizer global parameters Shut Down Equalizer perform a clean shut down of the Equalizer system so that the power can be safely turned off Log Out log out and end the administration session Configure displays a submenu with five options for modifying the Equalizer global parameters Change Passwo...

Page 47: ... viewing For example the local menu in the Server Parameters page enables you to change the server s parameters plot the server s history or delete the server Figure 21 Local menu Monitoring Equalizer Operation The Equalizer Administration interface provides several monitoring mechanisms that allow you to view Global configuration information and connection statistics for Equalizer A status summar...

Page 48: ...qualizer parameters section shows the following information Equalizer Version the version of the Equalizer software that s currently running External Address the IP address configured as Equalizer s external address Internal Address the IP address configured as Equalizer s internal address Stale Connection Timeout the number of seconds before a stale connection will be dropped Passive FTP Translat...

Page 49: ...s summary displays the status at the time the page was loaded To set this information to automatically refresh select a refresh interval and click the Set button The cluster summary lists the configured clusters and the status of each server in the cluster Servers shown in green are currently active Servers shown in yellow are configured as hot spares Servers shown in red are down Equalizer monito...

Page 50: ...og The System Event Log displays start up and server status messages You can view the last 20 50 100 200 500 or 1000 entries To view the event log 1 Log into the Equalizer Administration interface with view or edit access 2 Select Event Log from the View menu in the main menu bar The event log is displayed in the right frame Figure 24 Viewing the system event log To change the number of items disp...

Page 51: ...ons are plotted for the previous five minutes To change the information plotted select the categories and duration you want to plot and click the Plot button To zoom in on a portion of the graph click the area that you are interested in Five values can be plotted for a cluster Active connections the total number of active connections on the servers in the cluster Service time the average service t...

Page 52: ...tions in Plotting Server Performance on page 43 Figure 26 Viewing a cluster s graphical history Displaying Server Information The Server Parameters provide information about a particular server including connection statistics and the current configuration To display a server s parameters 1 Log into the Equalizer Administration interface with view or edit access 2 In the left frame click the name o...

Page 53: ... performance history 1 Log into the Equalizer Administration interface with view or edit access 2 In the left frame click the name of the server whose history you want to view 3 Select Plot Server History from the local menu in the Server Parameters frame The graphical history for the selected server is displayed By default the active connections service time computed load and dynamic weight are p...

Page 54: ...mprove cluster wide performance by increasing the server s dynamic weight to direct more traffic to it Such adjustments to the server s weight will in turn affect its computed load value Dynamic weight the percentage of incoming traffic that is being dispatched to this server For example if there are three servers in the cluster with dynamic weights of 100 80 and 120 the first server will get 100 ...

Page 55: ...ters that have been configured For more information about Envoy see Chapter Administering Geographic Clusters To view the cluster wide parameters 1 Log into the Equalizer Administration interface with view or edit access 2 In the left frame click the name of the geographic cluster whose parameters you want to view The Geographic Cluster Parameters page is displayed in the right frame Figure 29 Vie...

Page 56: ...low medium fast or fastest This value controls how aggressively Equalizer adjusts the site s dynamic weights See Adding a Geographic Cluster on page 87 for more information about the responsiveness settings Plotting Geographic Cluster Performance If Envoy is installed the Plot Geographic Cluster feature enables you to view a graphical representation of the performance history for the selected geog...

Page 57: ...ted for a cluster Request Rate the number of requests received for the cluster per minute Active Requests the number of requests that Equalizer is in the process of routing Network Latency the average triangulation time when at least one site was able to respond Excludes clients for which the default site was selected Site Summary Shows the number of requests directed to all sites in the cluster f...

Page 58: ...eographic Cluster the name of the geographic cluster to which this site belongs Site the site s name Site IP Address the IP address of the site Static Weight the static weight assigned to the site Default Site indicates whether or not this site is being used as the default site Resource the IP address and port of the resource being monitored for this site Agent s Address the IP address of the Equa...

Page 59: ...umber of active requests and load balancing variables Plotting Site Performance If Envoy is installed the Plot Site feature enables you to view a graphical representation of the performance history for the selected site To plot the performance history for a site 1 Log into the Equalizer Administration interface with view or edit access 2 In the left frame click the name of the site whose history y...

Page 60: ...his site during the period plotted Figure 32 Viewing a site s graphical history Configuring Equalizer Operation You can modify Equalizer s configuration through the Equalizer Administration interface and Set up a failover configuration with two Equalizers Enable outbound network address translation for reserved networks Enable passive FTP connections Configure stale connection handling Enable stic...

Page 61: ...ver When the failed unit is brought back online it assumes the backup role until another failure occurs or its sibling is rebooted To set up a failover configuration perform the following procedure on both Equalizers 1 Log into the Equalizer Administration interface with edit access 2 Select Configure Failover from the Equalizer menu in the main menu bar The Change Equalizer Parameters dialog is d...

Page 62: ...ualizers reboot The console messages should indicate that each Equalizer has successfully assumed the PRIMARY or BACKUP role Enabling Outbound NAT If you re using a reserved network configuration and the servers placed on the non routable network need to be able to communicate with hosts on the Internet you have to configure Equalizer to perform outbound network address translation NAT When outbou...

Page 63: ...ions The stale connection timeout is the length of time that a partially open or closed connection will be maintained If a client fails to complete the TCP connection termination handshake sequence or sends a SYN packet but does not respond to the server s SYN ACK the connection is marked incomplete Connections in the incomplete state are reclaimed when the stale connection timeout expires When a ...

Page 64: ... same network To enable sticky network aggregation 1 Log into the Equalizer Administration interface with edit access 2 Select Configure TCP IP Options from the Equalizer menu in the main menu bar The Change Equalizer Parameters dialog is displayed in the right frame By default the TCP IP tab is visible Figure 37 Enabling sticky network aggregation 3 Enable sticky network aggregation by selecting ...

Page 65: ...hen a server fails or other critical events occur This is done through the Change Equalizer Parameters dialog You can forward Equalizer log information to another machine or specify a command to run when a particular event occurs Forwarding Equalizer Log Information Equalizer s internal log information can be forwarded to another machine that s running a syslog daemon To specify a Syslog Host to f...

Page 66: ...1 Log into the Equalizer Administration interface with edit access 2 Select Configure Events from the Equalizer menu in the main menu bar The Change Equalizer Parameters dialog is displayed in the right frame By default the Events tab is visible 3 In the Event Handling frame enter the command that you want to run when a server event occurs For example to send email to admin yourdomain com whenever...

Page 67: ...ssword field 6 Click the Set button Saving or Restoring Your Configuration You can use the Backup Restore Configuration command to save your Equalizer configuration to a file or load a saved configuration Backing Up Your Configuration To save your current configuration to a file 1 Log into the Equalizer Administration interface with edit access 2 Select Configure Backup Restore Configuration from ...

Page 68: ...o restore a saved configuration 1 Log into the Equalizer Administration interface with edit access 2 Select Configure Backup Restore Configuration from the Equalizer menu in the main menu bar The Backup Restore Equalizer Configuration dialog is displayed in the right frame Figure 43 Restoring a saved onfiguration 3 Click Browse to locate and select the configuration file that you want to use to re...

Page 69: ...ualizer Administration interface with edit access 2 Select Shut Down from the Equalizer menu in the main menu bar A confirmation dialog is displayed Figure 44 Shutdown confirmation dialog 3 In the confirmation dialog click OK to confirm that you really want to shut down Equalizer Click Cancel to abort the shutdown request Clicking OK immediately initiates the shutdown cycle After 30 seconds it is ...

Page 70: ...Chapter 4 Administering Equalizer Operation 60 Equalizer Installation and Administration Guide ...

Page 71: ...Equalizer Installation and Administration Guide 61 5 Administering Virtual Clusters Working with Virtual Clusters 62 Working with Servers 75 Specifying Layer 7 Rules 79 ...

Page 72: ... and various load balancing criteria Supports Layer 7 load balancing Generic TCP the cluster handles TCP based requests and can route requests based on configured load balancing criteria and the IP address and TCP port number Load balancing based on the generic connection protocols can be more efficient but routing decisions cannot take into account the content of the request Supports Layer 4 load...

Page 73: ... Round Robin Server Agent or Static Weight See Configuring a Cluster s Load Balancing Options on page 64 for more information Load Balancing Response The load balancing responsiveness setting for this cluster Slow Medium or Fast See Configuring a Cluster s Load Balancing Options on page 64 for more information Server Agent Port The port used to contact the server agents Use Server Agent Enable thi...

Page 74: ...as the client address because the TCP connection to the client is terminated when the request is routed Enable Persistence Enable this option to use cookies to maintain a persistent session between a client and a particular server Always Use Cookie Enable this option to include a cookie in the response whether or not the server actually set a cookie Cookie Lifetime The length of time that the cook...

Page 75: ... are distributed equally among all of the servers in the cluster The first incoming request is dispatched to the first server the second to the second server and so on When the last server is reached the cycle repeats If Equalizer detects that a server in the cluster is DOWN no requests are dispatched to that server The round robin load balancing policy does not take advantage of Equalizer s Adapt...

Page 76: ... time and server agent value are still taken into account so that the server is not overloaded Server Agent the highest percentage of requests is dispatched to the server with the lowest server agent value Other server values such as the number of connections and response time are also taken into account to avoid overloading the server 5 Specify the Load Balancing Responsiveness This value control...

Page 77: ...essive optimization threshold Medium 17 5 Fast 25 most aggressive optimization threshold 6 Click the Set button Aggressive Load Balancing After fine tuning the static weights of each server in the cluster you might discover that Equalizer is not adjusting the dynamic weights of the servers at all the dynamic weights are very stable even under heavy load In this case you might want to set the clust...

Page 78: ...gured to use server agents Equalizer periodically contacts the server agent daemon running on each server and downloads the server performance statistics Server agents can also be customized to report on server resource availability enabling Equalizer to stop sending requests to a server if a database or other vital resource is unavailable For information about writing your own server agents and u...

Page 79: ... When cookie based persistence is used for HTTP and HTTPS clusters Equalizer stuffs a cookie into the server s response header on its way back to the client This cookie uniquely identifies the server to which the client was connected and is included in subsequent requests from the client to the same cluster Equalizer can use the information in the cookie to route the requests back to the same serv...

Page 80: ...ookie Path field 8 To restrict presentation of the cookie to requests directed to servers whose host name is within the specified domain enter it in the Cookie Domain field Enabling Sticky Connections Sticky connections are used to maintain persistent sessions for generic TCP and UDP clusters that do not support L7 load balancing The sticky time period is the length of time that Equalizer ensures ...

Page 81: ...Cluster www coyotepoint com https Server srv1 Server srv2 To enable sticky connections 1 Log into the Equalizer Administration interface with edit access 2 In the left frame click the name of the cluster you want to configure The Cluster Parameters are displayed in the right frame 3 Select Change Cluster Parameters from the local menu in the Cluster Parameters frame The Change Cluster dialog is di...

Page 82: ... to an HTTP server and request an HTML page Figure 51 Retrieving content from a server via telnet Equalizer can perform the same exchange automatically and verify the server s response by checking the returned data against an expected result You control what information is used to perform the verification by specifying an ACV Probe String and an ACV Response string Equalizer uses the probe string ...

Page 83: ...rtificates issued by Trusted Root Certificate Authorities as well as certificates issued by Certificate Authorities that do not have their own Trusted Root CA certificates If your certificate is issued by a C A that does not have it s own Trusted Root CA certificate you need to install both your server certificate and a chained root certificate for the CA For more information about chained certifi...

Page 84: ...TAfBgkq BgNVBAMTE3d3dy5jb3lvdGVwb2ludC5jb20xITAfBgkqhkiG9w0BCQEWEmNhQGNv eW90ZXBvaW50LmNvbTCBnzANBgkqhkiG9w0BAQEFAAOBjQAwgYkCgYEAunPJaj4h Sa geeUxP2m UeRMnjCWF9pSO drOLUFfMbvN6X gqO5tlFpB1a9i0kqE4KTmOQX 28P1H8z2wmQgkAiZ lVRypjpRmhOpKxn1hojMxkP KNLZkKjyHdCTb9u6qLS9JSE D vuO7oSBgjcK6dPsH9UBmOVzdg ye6PRVBPINWVLemXcyECQQDn6ppe5YOt0Anf DAOZA0GDSUBG2FZZ53iUp97Hi G0V93VMuzfP853QUsMQwR66ArAtOzlsHG JbdD Ef...

Page 85: ...al clusters Each server in a cluster uses Equalizer as the gateway for any response packets to clients that contacted the server through a virtual cluster address However Equalizer does not need to be configured as the gateway for the servers in an L7 clusters if IP spoofing is disabled for the cluster To add a server to an existing virtual cluster 1 Log into the Equalizer Administration interface...

Page 86: ...r assigns servers with a higher static weight a higher percentage of the load The relative values of server static weights are more important than the actual values For example if you have two servers in a cluster and one has roughly twice the horsepower of the other setting the static weights to 50 and 100 is equivalent to setting the static weights to 100 and 200 If Equalizer is performing adapt...

Page 87: ... local menu in the Server Parameters frame The Change Server Parameters dialog is displayed in the right frame Figure 54 Changing a server s static weight 4 Enter the new weight in the Static Weight field 5 Click the Set button Setting Static Weights for Homogenous Clusters If all of the servers in a cluster have the same hardware and software configurations their static weights should initially b...

Page 88: ...he server no longer has any active connections before you shut it down or delete it from a cluster When a server s static weight is set to zero Equalizer will not send any new requests to that server Connections that are already established continue to exist until the client and server application end them or they time out because they are idle To shut down servers in a generic TCP or UDP L4 clust...

Page 89: ...ing Layer 7 Rules Equalizer s support for Layer 7 content sensitive load balancing enables you to define match rules for routing HTTP and HTTPS requests according to the content of the request For each virtual cluster you can specify any number of match rules For each match rule you then specify the subset of servers that can handle requests that meet the rule criteria A match rule consists of a m...

Page 90: ...ch you want to add the rule 3 Select Add Match Rule from the local menu in the Cluster Parameters frame The Create New Match Rule dialog is displayed in the right frame Figure 55 Creating a match rule 4 Enter a name for the new rule in the Match Name field 5 Select the request content that you want to base the rule on from the Request Attribute list Host header the name of the host to which the re...

Page 91: ...e specified value The selected request content is not equal to the specified value 7 Specify the value that you want to compare the request content to in the Value field 8 To specify a complex match expression you can add additional expression statements a Click the Continue button b Select the Boolean operator you want to use to join the new expression For example to match requests that meet the ...

Page 92: ...You can remove expressions from your match rule by clicking the Delete button next to the expression you want to remove You can also insert expressions in a particular location by selecting the location in the match rule display 9 When you are done specifying expressions for your match rule click the Commit button Modifying a Match Rule To edit an existing match rule 1 Log into the Equalizer Admin...

Page 93: ...g match rule 1 Log into the Equalizer Administration interface with edit access 2 In the left frame click the name of the match rule you want to delete 3 Select Delete Match Rule from the local menu in the Match Rule frame Figure 58 Deleting a match rule 4 Confirm that you want to permanently remove the match rule Adding a Server to a Match Rule To associate a subset of the servers in the virtual ...

Page 94: ...4 Select the server that you want to add to the rule A server cannot be added to more than one match rule within a cluster 5 Click OK to add the selected server Removing a Server from a Match Rule To remove a server from a match rule 1 Log into the Equalizer Administration interface with edit access 2 In the left frame click the name of the server that you want to remove from the rule Figure 60 Se...

Page 95: ...Equalizer Installation and Administration Guide 85 6 Administering Geographic Clusters Geographic Load Balancing with Envoy 86 Working with Geographic Clusters 87 Working with Sites 90 ...

Page 96: ...has an Envoy enabled Equalizer and any number of servers Once you ve completed the normal Equalizer installation and configuration at each location you can install Envoy and configure your authoritative name server to work with Envoy When you ve completed the Envoy installation and DNS configuration described in this section you can set up the geographic clusters and define the available sites for...

Page 97: ...ks you need to configure the firewalls so that Envoy sites communicate with each other on UDP ports 5300 and 5301 The firewall must allow traffic on these ports to pass between Equalizer Envoy sites Envoy sites and clients can exchange packets on UDP port 53 The firewall must allow traffic on this port to flow freely between an Envoy server and any Internet clients so that clients trying to resolv...

Page 98: ...it a greater variance in the relative weights assigned to sites A slow setting causes site measurements to be averaged over a longer period of time before they are applied to the cluster wide load balancing and tend to ignore spikes in cluster measurements caused by intermittent network glitches The Medium setting is recommended as a starting point Geographic Cluster Name The fully qualified domai...

Page 99: ...hese parameters are configured independently for each geographic cluster For more information about the load balancing policy and responsiveness settings see Adding a Geographic Cluster on page 87 You might want to fine tune the static weights of the geographic cluster s sites to optimize cluster performance For more information see Adjusting a Site s Static Weight on page 92 To change a geographi...

Page 100: ...me before they are applied to the cluster wide load balancing and tend to ignore spikes in cluster measurements caused by intermittent network glitches 6 Click the Set button Deleting a Geographic Cluster To delete a geographic cluster 1 Log into the Equalizer Administration interface with edit access 2 In the left frame click the name of the geographic cluster you want to delete The Geographic Cl...

Page 101: ...an Equalizer cluster that s returned if the site is chosen Keepalive How often the Agent should probe the resource The default value of 100 results in the resources availability being tested every 100 seconds Static Weight This is a user defined value between 10 and 200 that represents the site s capacity This value is similar to a server s static weight Use the default of 100 if all sites are sim...

Page 102: ...nd 100 is equivalent to setting the static weights to 100 and 200 Dynamic site weights can vary from 50 150 of the assigned static weights To optimize geographic cluster performance you might need to adjust the static weights of the sites in the cluster based on their performance Site weights can range from 10 to 200 When setting up sites in a geographic cluster you should set each site s static w...

Page 103: ...ic cluster 1 Log into the Equalizer Administration interface with edit access 2 In the left frame click the name of the site you want to delete The Site Parameters are displayed in the right frame 3 Select Delete Site from the local menu in the Site Parameters frame 4 When prompted confirm that you really want to remove the site by clicking OK ...

Page 104: ...Chapter 6 Administering Geographic Clusters 94 Equalizer Installation and Administration Guide ...

Page 105: ...6 Clients time out while trying to contact a virtual cluster 96 Can t view Equalizer administration pages 96 Equalizer administration page takes a long time to display 97 Equalizer doesn t respond to pings to the admin address 97 Browser hangs when trying to connect via FTP to an FTP cluster 97 ...

Page 106: ...nt is on the same network as the servers the servers will likely try to send data packets directly to the client bypassing Equalizer This can be corrected by adding host routes on the servers so that the servers send their reply packets via Equalizer Possible cause No active servers in the virtual cluster Check the Equalizer Summary page Are there any servers in that virtual cluster Are all of the...

Page 107: ... keyboard and monitor cycle the power and watch the startup diagnostic messages Possible cause Equalizer isn t connected to your network Check the network wiring Possible cause Administration address not configured on interface FXP0 Use the Equalizer Configuration Utility to set the IP address and netmask for interface FXP0 Be sure to commit your changes Browser hangs when trying to connect via FT...

Page 108: ...Chapter 7 Troubleshooting 98 Equalizer Installation and Administration Guide ...

Page 109: ...Equalizer Installation and Administration Guide 99 A Using Server Agents Introducing Server Agents 100 Custom Server Agents 100 ...

Page 110: ... load balancing When server agents are enabled Equalizer periodically probes the agent at each server s IP address through the configured agent port Equalizer uses the collected server agent values when performing adaptive load balancing calculations You configure Equalizer to use server agents through the Change Cluster dialog For more information see Configuring a Cluster to Use Server Agents on...

Page 111: ...Equalizer Installation and Administration Guide 101 B Using Reserved IP Addresses Reserved IP Addresses 102 Configuration Worksheet for Using Reserved IP Addresses 103 ...

Page 112: ... 10 0 0 0 the now defunct Arpanet as the internal network and assign virtual server addresses out this network for the servers Figure 65 Reserved Internal Network If servers placed on a non routable network will need to communicate with hosts on the Internet for any reason such as performing DNS resolution or sending email you need to configure Equalizer to perform outbound NAT network address tra...

Page 113: ...T button Configuration Worksheet for Using Reserved IP Addresses 1 What is the reserved network to be used for the internal network Equalizer uses this set of address to balance the load across the servers Equalizer uses the internal network to forward connections to the HTTP daemons running on the servers Example 10 0 0 0 netmask 255 0 0 0 or 192 168 2 0 netmask 255 255 255 0 2 What is the Equali...

Page 114: ...Appendix B Using Reserved IP Addresses 104 Equalizer Installation and Administration Guide ...

Page 115: ...re two of them the first may not exceed the second An atom followed by a bound that contains one integer i and no comma matches a sequence of exactly i matches of the atom An atom followed by a bound that contains one integer i and a comma matches a sequence of i or more matches of the atom An atom followed by a bound containing two integers i and j matches a sequence of i through j inclusive matc...

Page 116: ...ting sequence includes a ch collating element then the RE ch c matches the first five characters of chchcc Within a bracket expression a collating element enclosed in and is an equivalence class standing for the sequences of characters of all collating elements equivalent to that one including itself If there are no other equivalent collating elements the treatment is as if the enclosing delimiter...

Page 117: ...nger than no match at all For example bb matches the three middle characters of abbbc wee week knights nights matches all ten characters of weeknights when is matched against abc the parenthesized subexpression matches all three characters and when a is matched against bc both the whole RE and the parenthesized subexpression match the null string ...

Page 118: ...Appendix C Regular Expression Format 108 Equalizer Installation and Administration Guide ...

Page 119: ...n and Administration Guide 109 D Equalizer Configuration File Modifying the Equalizer Configuration File 110 Equalizer Parameters 111 Cluster Specific Parameters 113 Server Specific Parameters 116 Match Group Parameters 117 ...

Page 120: ...al parameters are specified at the top of the configuration file It also contains a block for each cluster that defines the cluster parameters and the server and match rule parameters for each server and match rule configured for the cluster For example client_timeout 100 sequence 1 checksum 124356 connect_timeout 32 probe_interval 5 probe_timeout 34 strikeout_threshold 35 log_hours 24 plot_clip 3...

Page 121: ...pplicable for L7 Mininum 10 Maximum 600 Default 100 server_timeout This is the time in tenths of a second before the connection to the client is closed due to the server being unresponsive Only applicable for L7 Minimum 150 Maximum 2147483647 Default 9000 probe_delay This is the delay in seconds between successive high level probes after a successful probe Minimum 0 Maximum 60 Default 10 probe_int...

Page 122: ...ging and not being able to send the entire valid request log_hours The number of hours that the system saves performance history information For example if log_hours is set to 72 the system will be able to plot three days of performance statistics The maximum value for log_hours is 168 7 days plot_clip The plot_clip parameter enables you to specify a clipping value for the performance history data...

Page 123: ...s are enables and the agent does not respond the server will be marked DOWN Cluster Specific Parameters The following parameters can only appear within a cluster body and the scope of the parameter is the virtual cluster unless overridden by a match group parameter setting protocol The protocol of the virtual cluster must always be specified and it should be specified first as the protocol selecti...

Page 124: ... If specified a connection will be made to this port on the server periodically to determine the load on that server sticky_time This is the time in some fractions of a second that a sticky record persists This is only meaningful for L4 protocols ACV_probe The active content verification probe string can be specified If provided during the periodic probes to determine if the server is alive this s...

Page 125: ...e global environment spoof Enable client address spoofing For L7 clusters the Equalizer terminates the TCP connection This means that the server eventually selected will think that the client address is that of the Equalizer unless spoofing is enabled Just the IP address is spoofed not the port inter_cluster_sticky When enabled Equalizer ensures that requests from a particular user are directed to...

Page 126: ...2 Always perform stuff using Set Cookie2 Currently this is not supported Server Specific Parameters The following parameters can appear within a server block Currently no protocols define protocol specific server flags port This is the TCP or UDP port number associated with the server The default value of this may be provided by the protocol such as port 80 in the case of HTTP ip This is the IP ad...

Page 127: ...ps support the following functions any This matches any L7 protocol request HTTP Specific Match Group Parameters flags All the HTTP specific cluster flags can be set To clear out those inherited from the cluster it is necessary to use none as in flags none persist The following parameters are also available cookie_scheme cookie_max_age cookie_domain cookie_path cookie_flags HTTP Specific Match Gro...

Page 128: ...matches the indicated regular expression dirname name True if the directory name portion of the URI matches exactly header_regex header re True if the specified header is present in the request and the specified regular expression matches the text of the header HTTPS Specific Match Group Parameters Match groups in HTTPS protocol clusters can specify the same parameters as HTTP protocol clusters HT...

Page 129: ...100 Base TX auto detecting 4 pair Category 5 wiring only System I O DB9 RS 232 Serial Dimensions EIA 1U Rack mount Enclosure Height 1 75 in 45 mm Width 17 in 430 mm Depth 18 in 470 mm Power 110 240 VAC Auto switching 50 60 Hz Environmental Operating temperature 0º to 45ºC Relative humidity 5 to 95 40ºC ...

Page 130: ...Appendix E Technical Specifications 120 Equalizer Installation and Administration Guide ...

Page 131: ... Point Systems Customer agrees not to disclose provide or otherwise make available such trade secrets or copyrighted material in any form to any third party without the prior written consent of Coyote Point Systems Customer agrees to implement reasonable security measures to protect such trade secrets and copyrighted material Title to Software and documentation shall remain solely with Coyote Poin...

Page 132: ...TY LASTS OR THE EXCLUSION OR LIMITATION OF INCIDENTAL OR CONSEQUENTIAL DAMAGES FOR CONSUMER PRODUCTS IN SUCH STATES OR COUNTRIES SOME EXCLUSIONS OR LIMITATIONS OF THIS LIMITED WARRANTY MAY NOT APPLY TO YOU This Limited Warranty applies to the Coyote Point Systems software and hardware products sold by Coyote Point Systems Inc its subsidiaries affiliates authorized resellers or country distributors...

Page 133: ... be in the original manufacturer s undamaged packaging along with all accessories shipped with the original product including cables handles and manuals If you did not retain the original packaging materials there may be a charge for replacement packaging If a defective product is returned the cost of incoming freight and insurance is the responsibility of the customer The cost of return freight i...

Page 134: ...YOU HAVE PAID FOR THE PRODUCT OR THE COST OF REPAIR OR REPLACEMENT OF ANY SOFTWARE OR HARDWARE COMPONENTS THAT MALFUNCTION IN CONDITIONS OF NORMAL USE COYOTE POINT SYSTEMS IS NOT LIABLE FOR ANY DAMAGES CAUSED BY THE PRODUCT OR THE FAILURE OF THE PRODUCT TO PERFORM INCLUDING ANY LOST PROFITS OR SAVINGS OR DATA OR SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES OR PUNITIVE DAMAGES COYOTE POINT SYSTEMS I...

Page 135: ...E OF NEW YORK UNITED STATES OF AMERICA WITHOUT REGARD TO THE CONFLICT OF LAWS PROVISIONS THEREOF THE UNITED NATIONS CONVENTION ON CONTRACTS FOR THE INTERNATIONAL SALE OF GOODS SHALL NOT APPLY TO THESE TERMS IN ANY RESPECT THIS DISCLAIMER OF WARRANTIES AND LIMITED WARRANTY ARE SUBJECT TO THE TERMS OF SALE OF THE COYOTE POINT SYSTEMS PRODUCT ...

Page 136: ...Appendix F License and Warranty 126 Equalizer Installation and Administration Guide ...

Page 137: ...nal network external network The subnet to which the client machines and possibly the Internet or an Intranet are connected FTP cluster A virtual cluster providing service on the FTP control port port 21 FQDN Fully Qualified Domain Name fully qualified domain name The absolute domain name of a host on the Internet A fully qualified domain name is written relative to the root domain and unambiguous...

Page 138: ...e physical server server address The IP address of a server on the internal interface Multiple IP addresses can be aliased to a single physical server server endpoint An IP address port pair that identifies a physical or virtual server on the internal network to which Equalizer can route connection requests server weight A value that indicates the relative proportion of connection requests that a ...

Page 139: ...44 68 site 48 49 aggressive load balancing 67 algorithm 65 always use cookie 64 authoritative name server 7 configuring 86 average triangulation time 49 B backup 13 mode 14 server 76 unit 13 51 browser preferences 35 C change configuration 51 55 56 changing a server s static weight 76 a site s static weight 92 the administration password 27 57 the console password 27 checklist configuration 31 cli...

Page 140: ... 3 68 date setting 27 default route 29 defining a match rule 80 deleting a cluster 75 a geographic cluster 90 a match rule 83 a server 79 a server from a match rule 84 a site from a geographic cluster 93 device probe 24 diagnostic messages 24 displaying cluster information 40 cluster summary 39 Equalizer information 38 server information 42 system log 40 DNS 7 requests 39 TTL 46 domain 7 name 7 na...

Page 141: ...oblems 96 installing Envoy 86 interface administration 34 logging into 35 character based 24 external 10 internal 10 internal address 29 interface 10 12 interface parameters 26 network 10 20 Internet 11 Intranet 11 IP address 10 26 30 aliasing 11 reserved 14 site 48 site agent 91 IP aliases using 11 J javascript enabled 34 K keepalive 48 91 kernel 14 keyboard application mode 21 L L4 clusters 70 L...

Page 142: ...l 10 latency 6 47 50 local area 20 parameters configuring 25 single 12 Network Configuration window 25 NFS server clusters 4 ntmeasd exe 68 O operation modes 38 optimization threshold 67 optimizing cluster performance 77 92 optimizing geographic cluster performance 89 options load balancing 64 outbound packets 10 P packet 29 ARP 14 outbound 10 request 10 response 10 SYN 53 parameters internal inte...

Page 143: ...ess 30 port 76 removing from a match rule 84 resource availability 68 response time 66 shutting down 78 static weight 76 status 40 weight 76 server agent 42 44 63 66 68 custom 100 parameters 41 port 63 using 68 value 66 Server Parameters 42 service time 41 44 setting date and time 27 stale connection timeout 53 static weights for homogenous clusters 77 static weights for mixed clusters 78 time zon...

Page 144: ...5 using a second Equalizer as a backup 13 Equalizer as a gateway between networks 11 Equalizer in a single network environment 12 IP aliases 11 reserved IP addresses 14 server agents 68 V view menu 36 view mode 35 viewing a cluster s graphical history 42 46 a server s graphical history 45 a site s graphical history 49 cluster information 41 Equalizer information 38 virtual cluster 30 adding 62 add...

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