Troubleshooting Vrrp - 3Com 8800 Configuration Manual

3Com Switch 8800 Configuration Guide

41.5 Troubleshooting VRRP

As the configuration of VRRP is not very complicated, almost all the malfunctions can
be found through viewing the configuration and debugging information. Here are some
possible failures you might meet and the corresponding troubleshooting methods.
I. Fault 1: Frequent prompts of configuration errors on the console
This indicates that an incorrect VRRP packet has been received. It may be because of
the inconsistent configuration of another switch within the virtual router, or the attempt
of some devices to send out illegal VRRP packets. The first possible fault can be solved
through modifying the configuration. And as the second possibility is caused by the
malicious attempt of some devices, non-technical measures should be resorted to.
II. Fault 2: More than one Masters existing within the same virtual router
There are also 2 reasons. One is short time coexistence of many Master switches,
which is normal and needs no manual intervention. Another is the long time
coexistence of many Master switches, which may be because switches in the virtual
router cannot receive VRRP packets from each other, or receive some illegal packets.
To solve such problems, an attempt should be made to ping among the many Master
switches, and if such an attempt fails, check the device connectivity. If they can be
pinged, check the VRRP configuration. For the configuration of the same VRRP virtual
router, complete consistence for the number of virtual IP addresses, each virtual IP
address, timer duration and authentication type must be guaranteed.
III. Fault 3: Frequent switchover of VRRP state
Such problem occurs when the virtual router timer duration is set too short. So the
problem can be solved through prolonging this duration or configuring the preemption
delay.
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Chapter 41 VRRP Configuration