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Configure the source to send the configured source interface IP address instead of using its front-end IP address in the ICMP
unreachable messages and in the
traceroute
command output. Use the
ip icmp source-interface
interface
or the
ipv6 icmp source-interface
interface
commands in Configuration mode to enable the ICMP error messages to be
sent with the source interface IP address. This functionality is supported on loopback, VLAN, port channel, and physical interfaces
for IPv4 and IPv6 messages. feature is not supported on tunnel interfaces. ICMP error relay, PATH MTU transmission, and
fragmented packets are not supported for tunnel interfaces. The traceroute utilities for IPv4 and IPv6 list the IP addresses of the
devices in the hops of the path for which ICMP source interface is configured.
Configuring the Duration to Establish a TCP Connection
You can configure the duration for which the device must wait before it attempts to establish a TCP connection. Using this
capability, you can limit the wait times for TCP connection requests. Upon responding to the initial SYN packet that requests a
connection to the router for a specific service (such as SSH or BGP) with a SYN ACK, the router waits for a period of time for the
ACK packet to be sent from the requesting host that will establish the TCP connection.
You can set this duration or interval for which the TCP connection waits to be established to a significantly high value to prevent the
device from moving into an out-of-service condition or becoming unresponsive during a SYN flood attack that occurs on the device.
You can set the wait time to be 10 seconds or lower. If the device does not contain any BGP connections with the BGP neighbors
across WAN links, you must set this interval to a higher value, depending on the complexity of your network and the configuration
attributes.
To configure the duration for which the device waits for the ACK packet to be sent from the requesting host to establish the TCP
connection, perform the following steps:
1.
Define the wait duration in seconds for the TCP connection to be established.
CONFIGURATION mode
Dell(conf)#ip tcp reduced-syn-ack-wait <9-75>
You can use the
no ip tcp reduced-syn-ack-wait
command to restore the default behavior, which causes the wait
period to be set as 8 seconds.
2.
View the interval that you configured for the device to wait before the TCP connection is attempted to be established.
EXEC mode
Dell>show ip tcp reduced-syn-ack-wait
Enabling Directed Broadcast
By default, Dell Networking OS drops directed broadcast packets destined for an interface. This default setting provides some
protection against denial of service (DoS) attacks.
To enable Dell Networking OS to receive directed broadcasts, use the following command.
•
Enable directed broadcast.
INTERFACE mode
ip directed-broadcast
To view the configuration, use the
show config
command in INTERFACE mode.
Resolution of Host Names
Domain name service (DNS) maps host names to IP addresses. This feature simplifies commands such as Telnet and FTP by allowing
you to enter a name instead of an IP address.
Dynamic resolution of host names is disabled by default. Unless you enable the feature, the system resolves only host names entered
into the host table with the
ip host
command.
IPv4 Routing
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Содержание S4048-ON
Страница 1: ...Dell Configuration Guide for the S4048 ON System 9 9 0 0 ...
Страница 146: ...Figure 14 BFD Three Way Handshake State Changes 146 Bidirectional Forwarding Detection BFD ...
Страница 477: ...Figure 68 Inspecting Configuration of LAG 10 on ALPHA Link Aggregation Control Protocol LACP 477 ...
Страница 480: ...Figure 70 Inspecting a LAG Port on BRAVO Using the show interface Command 480 Link Aggregation Control Protocol LACP ...
Страница 481: ...Figure 71 Inspecting LAG 10 Using the show interfaces port channel Command Link Aggregation Control Protocol LACP 481 ...
Страница 522: ...Figure 87 Configuring Interfaces for MSDP 522 Multicast Source Discovery Protocol MSDP ...
Страница 523: ...Figure 88 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 523 ...
Страница 524: ...Figure 89 Configuring PIM in Multiple Routing Domains 524 Multicast Source Discovery Protocol MSDP ...
Страница 528: ...Figure 91 MSDP Default Peer Scenario 1 528 Multicast Source Discovery Protocol MSDP ...
Страница 529: ...Figure 92 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 529 ...
Страница 530: ...Figure 93 MSDP Default Peer Scenario 3 530 Multicast Source Discovery Protocol MSDP ...
Страница 633: ...Policy based Routing PBR 633 ...
Страница 777: ...Figure 119 Single and Double Tag TPID Match Service Provider Bridging 777 ...
Страница 778: ...Figure 120 Single and Double Tag First byte TPID Match 778 Service Provider Bridging ...