02-18-2009 01:27 PM - edited 03-15-2019 04:19 PM
have multiple CP7911s flapping between the data ahd voice vlan both when idle and during a call.
-Setup-
UCM 6.1(2)
Cat3750
CP7911
-Port Config Looks Like-
switchport access vlan 4
switchport voice vlan 512
Have upgraded and downgraded switch firmware. Have upgraded and downgraded phone firmware.
Phone log shows the following.
NOT 08:47:24.959415 CDP-D: vvlan changed --> New:4096 old:512 4096
NOT 08:47:24.964826 CDP-D: vlan Configured --> New:4096 old:4 :4096
NOT 08:47:25.008963 CDP-D: vvlan changed --> New:512 old:4096 512
NOT 08:47:25.014483 CDP-D: vlan Configured --> New:4 old:4096 :4
NOT 09:01:24.959628 CDP-D: vvlan changed --> New:4096 old:512 4096
NOT 09:01:24.965456 CDP-D: vlan Configured --> New:4096 old:4 :4096
Anyone have any ideas what may be causing this.
02-18-2009 01:49 PM
Hello Lupe,
it looks like CDP communication is not working well.
To be noted that vlan 4096 as vlan 0 cannot be used for real switch ports they are reserved for internal use in switch.
You can see a circular sequence involving vlans 4, 512 and this 4096.
Also CDP messages are sent every 60 seconds but the first log lines are very close:
NOT 08:47:24.959415 CDP-D: vvlan changed --> New:4096 old:512 4096
NOT 08:47:24.964826 CDP-D: vlan Configured --> New:4096 old:4 :4096
NOT 08:47:25.008963 CDP-D: vvlan changed --> New:512 old:4096 512
NOT 08:47:25.014483 CDP-D: vlan Configured --> New:4 old:4096 :4
I would try to span the switch port to a port with a sniffer like wireshark to see the CDP messages sent by the switch
Hope to help
Giuseppe
02-18-2009 03:28 PM
I did that to see if I saw anything weird, but I didn't think to look for CDP messages in the capture. I'll do it again and look for CDP.
Weird thing is I don't change CDP settings. All CDP settings are default.
Thanks.
02-19-2009 05:03 PM
after speaking with TAC, this turned out to be a bug in the cp7911 & cp7931 firmware.
CSCsu47079
TAC hooked me up with SCCP_7911_7906_8-4-3ES4 firmware for the 7911. it's looking good so far. a workaround was to reduce CDP timer to 15.
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