Brocade Communications Systems ICX 7250 series, Руководство по настройке

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Enabling ICMP redirect messages
You can enable and disable IPv4 ICMP redirect messages globally or on individual Virtual Ethernet (VE) interfaces but not on individual
physical interfaces.
NOTE
The device forwards misdirected traffic to the appropriate router, even if you disable the redirect
messages.
By default, IP ICMP redirect over global level is disabled and a Brocade Layer 3 switch does not send an ICMP redirect message to the
source of a misdirected packet in addition to forwarding the packet to the appropriate router. To enable ICMP redirect messages globally,
enter the following command at the global CONFIG level of the CLI:
device(config)# ip icmp redirect
Syntax: [no] ip icmp redirect
To disable ICMP redirect messages on a specific virtual interface, enter the following command at the configuration level for the virtual
interface:
Brocade(config-vlan-10)# interface ve 10
Brocade(config-vif-10)# no ip redirect
Syntax: [no] ip redirect
Configuring a default network route
The Layer 3 switch enables you to specify a candidate default route without the need to specify the next hop gateway. If the IP route table
does not contain an explicit default route (for example, 0.0.0.0/0) or propagate an explicit default route through routing protocols, the
software can use the default network route as a default route instead.
When the software uses the default network route, it also uses the default network route's next hop gateway as the gateway of last resort.
This feature is especially useful in environments where network topology changes can make the next hop gateway unreachable. This
feature allows the Layer 3 switch to perform default routing even if the default network route's default gateway changes.
The feature thus differs from standard default routes. When you configure a standard default route, you also specify the next hop
gateway. If a topology change makes the gateway unreachable, the default route becomes unusable.
For example, if you configure 10.10.10.0/24 as a candidate default network route, if the IP route table does not contain an explicit
default route (0.0.0.0/0), the software uses the default network route and automatically uses that route's next hop gateway as the default
gateway. If a topology change occurs and as a result the default network route's next hop gateway changes, the software can still use the
default network route. To configure a default network route, use the following CLI method.
If you configure more than one default network route, the Layer 3 switch uses the following algorithm to select one of the routes.
1. Use the route with the lowest administrative distance.
Configuring IP parameters - Layer 3 switches
Brocade FastIron Layer 3 Routing Configuration Guide
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