Chapter 15 high availability troubleshooting, Spontaneous failover activity, Unexpected fail-back activity – Znyx Networks bh5700 User Manual
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Chapter 15 High Availability Troubleshooting
The ATCA environment will usually contain a high-availability failover configuration between
two ATCA switches in the chassis. Note that the failover features are configurable and a switch
can be directed to fail over all of its processing when a single port or link goes down, or it can
perform a port-to-port or VLAN-to-VLAN failover where both partner switches are still
processing a portion of the network traffic.
Before replacing a switch that has gone out of service because of a switch-level failover, you
need to understand how the high-availability features have been configured. If the switch failover
was triggered by a port or link failure, make sure to isolate the cause for the link failure first, to
make sure the problem is not external to the switch (for example, a bad or loose cable for a wired
port).
Spontaneous Failover Activity
If while rebooting the inactive switch in a chassis causes the active switch to reboot and/or an
unexpected failover, you can try setting the zsp.conf file vrrp_msg_rate to 500.
The
VRRP_msg_rate
is the time in milliseconds between transmissions VRRP messages on the
inter-switch link (ISL). The VRRP protocol requires the absence of three VRRP messages before
concluding that the remote switch has failed. The
msg_rate
must match the
msg_rate
of all
siblings. Anything other than multiples of seconds does not conform to the VRRP specification,
and will only run with the
vrrpd
.
Unexpected Fail-back Activity
If unexpected fail-back activity is observed check to make sure that only one switch is setup as
the Master switch (
vrrpd –M option
) or the switches will oscillate. See the Ethernet Switch
Blade User’s Guide for more information on setting the failover priority level.
Ethernet Switch Blade User's Guide
release 3.2.2j
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