VOIPs were down

[Richard.Jeff]

Hi,

I faced an issue with the catalyst 4500 switch running code cat4500e-entservicesk9-mz.122-53.SG1.bin where all the 75 VOIPS connected to it went down all in a sudden.

In the switch logs i could see the below mssage:

Apr  7 15:39:27.334: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.228.
Apr  7 15:39:30.335: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.229.
Apr  7 15:48:53.601: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.232.
Apr  7 15:48:56.601: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.233.
Apr  7 15:48:59.602: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.234.
Apr  7 15:49:35.293: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.236.
Apr  8 06:15:10.681: %C4K_REDUNDANCY-5-CALENDAR_RATELIMIT: The calendar has been successfully synchronized to the standby supervisor24 times since last calendar syslog
Apr  8 08:26:15.201: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.240.
Apr  8 08:26:18.201: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.241.
Apr  8 08:26:21.201: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.242.
Apr  8 08:26:24.202: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.243.
Apr  8 08:26:27.202: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.244.
Apr  8 08:26:30.206: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.245.
Apr  8 08:26:33.218: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.246.
Apr  8 09:01:10.686: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.248.
Apr  8 10:17:01.207: %SYS-5-CONFIG_I: Configured from console by malayac on vty0 (10.200.52.15)
Apr  8 11:30:30.506: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.250.
Apr  8 11:30:33.515: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.251.
Apr  8 11:30:36.515: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.252.
Apr  8 11:30:39.515: %DHCPD-4-PING_CONFLICT: DHCP address conflict:  server pinged 10.155.191.253.
Apr  9 06:15:19.679: %C4K_REDUNDANCY-5-CALENDAR_RATELIMIT: The calendar has been successfully synchronized to the standby supervisor24 times since last calendar syslog
Apr 10 06:15:28.654: %C4K_REDUNDANCY-5-CALENDAR_RATELIMIT: The calendar has been successfully synchronized to the standby supervisor24 times since last calendar syslog
Apr 11 06:15:37.635: %C4K_REDUNDANCY-5-CALENDAR_RATELIMIT: The calendar has been successfully synchronized to the standby supervisor24 times since last calendar syslog

Apart from this there was no error message created relevent to this ip conflict error mesage.

The observatios as follows:

Some of the IP phones to say 15 in number came up automatically after sometime but the others were sill down.

Increased the DHCP pool range and then only two more VOIPs came up.

All the remainig VOIPS were still in configuring IP for a long time. Rebooted all thes VOIPs once and could see all came up.

What might be the cause of this problem? If anyone could give a hint..

Thanks in advance...

[Ton V Engelen]

Hi,

i ve had a similar issue with ap's that need dhcp. Not sure its the same.

Reason:

After i ve upgraded our 6500's , wism blades onboard, a large amount of aps booted at the same time after the 6500 came up and hence, a lot of dhcp requests were done at the same time and we ran into this issue.  Plus because of this half the wifi network went down.....

(the ap dhcp pools are on the 6500's )

Solution / work around

- clear ip dhcp conflicts,

Then when the lease time ran out...next day same issue. So,

- clear ip dhcp conflicts

- reboot a lot of aps so that the dhcp requests are not all send out from all ap's at the same time. Else we ll have the same issue tomorrow again.

The issue went away.

I think allhough the pool is big enough, there are iisues when all devices boot at the same time, plus an ap will use 2 or 3 ip addreses in a row when joining the controller during boot. Which explains the conflicts.

Hope it helps a bit.

Regards

Ton