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Community Member

about vtp domain

Dear all,

Why the device display red (unreachache)status when it is on line.

please help check attach.the switch is on line but it display unreachable.i already change management ip to another but it did not.


Cisco Employee

Re: about vtp domain

A device appears red on the topology map when Campus Manager cannot communicate with it via SNMP. This could be due to a variety of causes. The device may be down (but you say it's online), the SNMP credentials may have changed on the device, or the device may be busy, and not responding to SNMP queries quickly enough.

A quick way to troubleshoot this is to start a packet capture filtering on UDP port 161 traffic to this switch, then perform a Campus Data Collection for the switch. The packet capture should then give you an idea as to why the switch is unreachable. That said, a new Data Collection may succeed, so the switch may turn back to green.

Note: Campus Manager is not a fault management application, so do not assume that green devices are available and red devices are necessarily down.

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