Brocade Communications Systems ICX 7250 series, Configuration Manual

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In the following example, short-path forwarding is configured on a backup VRRP-E device, and a revert priority threshold is configured. If
the backup device priority falls below this threshold, short-path forwarding is disabled.
device# configure terminal
device(config)# router vrrp-extended
device(config-vrrpe-router)# interface ve 10
device(config-vif-10)# ip address 192.168.4.1/24
device(config-vif-10)# ip vrrp-extended vrid 5
device(config-vif-10-vrid-5)# backup priority 50
device(config-vif-10-vrid-5)# ip-address 192.168.4.254
device(config-vif-10-vrid-5)# short-path-forwarding revert-priority 50
device(config-vif-10-vrid-5)# activate
VRRP-E slow start timer
In a VRRP extended (VRRP-E) configuration, if a master device goes offline, the backup router with the highest priority takes over after
the expiration of the dead interval timer. When the original master device is back online, you can configure a slow-start timer interval that
extends the time interval beyond the dead interval before the original master device transitions back to the role of master device.
The slow-start interval allows additional time for routing protocols, for example OSPF, to converge without causing route flapping during
the transition from backup device to master device. Included in the VRRP-E slow-start timer feature are track port state changes and
restart options. The
use-track-port option implements a slow-start timer for the first tracked port "up" state change, in addition to the
VRRP-E initialization state. The restart option restarts the slow-start timer for subsequent tracked port "up" state changes.
NOTE
If you change the backup priority of a VRRP-E backup router to be higher than the priority of the original master device, the
slow-start timer will not work. The original master device will take over from the backup device immediately.
Configuring a VRRP-E slow-start timer
The slow-start timer is a VRRP-E interval timer that extends beyond the dead interval during a transition from the backup device that
assumed the master role to the original master device that is back online and has a higher priority.
In a VRRP extended (VRRP-E) configuration, if a master device goes offline, the backup router with the highest priority takes over after
the expiration of the dead interval timer. When the original master device is back online, you can configure a slow-start timer interval that
extends the time interval beyond the dead interval before the original master device transitions back to the role of master device.
1. Use the configure terminal command to enter global configuration mode.
device# configure terminal
2. To globally enable VRRP-E, enter the router vrrp-extended command.
device(config)# router vrrp-extended
3. Enter the slow-start command with options to configure the interval, in seconds, and whether tracked-port state changes
trigger the slow-start interval.
device(config-vrrpe-router)# slow-start 40 use-track-port restart
In this example, the slow-start timer interval is set to 40 seconds, and the slow-start timer also runs after the first and subsequent
tracked-port state changes.
device# configure terminal
device(config)# router vrrp-extended
device(config-vrrpe-router)# slow-start 40 use-track-port restart
VRRP-E slow start timer
Brocade FastIron Layer 3 Routing Configuration Guide
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