Nortel Networks WEB OS 212777 - Manual (Page 258)

Web OS 10.0 Application Guide
258 n Chapter 11: High Availability
212777-A, February 2002
When the hotstan option ( /cfg/slb/port x/hotstan ) is enabled and all hot-standby
ports have link, the virtual router group's priority is automatically incremented by the “track
other virtual routers” value. This action allows the switches to failover when a hot-standby port
loses link. Other enabled tracking features only have affect when all hot-standby ports on a
switch have link. The default virtual routers tracking value is 2 seconds. Keep in mind that this
is an automatic process that cannot be turned off.
N OTE – The VRRP hot-standby approach does not support single-link failover. If one hot-
standby port loses link, the entire switch must become master to eliminate loss of connectivity.
The forwarding states of non-hot-standby ports are not controlled via the hot-standby algo-
rithm, allowing the additional ports on the switches to provide added port density. The client
ports on both switches should be able to process or forward traffic to the master switch.
The inter-switch port state is only a place holder. Its presence forces the user to configure a
inter-switch link when hot-standby is globally enabled and prohibits the inter-switch link from
also being a hot-standby link for VRRP advertisements. These advertisements must be able to
reach the backup switch.
Synchronizing Configurations
The final piece in configuring a high-availability solution includes the addition of synchroniza-
tion options to simplify the manual configuration. Configuration options have been added to
refine what is synchronized, to whom, and to disable synchronizing certain configurations.
These options include proxy IP addresses, Layer 4 port configuration, filter configuration, and
virtual router priorities.
Also, a peer menu ( cfg/slb/sync/peer ) has been added to allow the user to configure
the IP addresses of the switches that should be synchronized. This provides added synchroni-
zation validation but does not require the users to enter the IP address of the redundant switch
for each synchronization.
N OTE – When using both VRRP and GSLB, you must change the /cfg/sys/wport
(Browser-Based Interface port) value of the target switch (the switch that is being synchro-
nized to) to a port other than port 80 before VRRP synchronization begins.
For more information on synchronizing configurations between two switches, see “Synchro-
nizing Configurations” on page 282 .