Hard Phones Unregistering Often.

[Rajan R]

Hey Guys,

We are deploying CUCM/CUPS 8.6 at loacation A. Location B is connected with a site to site VPN. At Location B Jabber and cipc are working fine but hard phones keep unregistering continuosly. Sometimes there is one way audio or the call drops. Sometimes the call continues when CUCM shows the phone has unregistered. A few times the TFTP load on the phone gets stuck at 0%. A few times its just as fine. The delay is around 330ms. Whyy does this happen ?

Thanks.

Varadarajan.R

[Aaron Harrison]

Probably because you have packet loss over the Internet?

[Rajan R]

There is no loss. I see 4 or 5 packet drops for every 1000. Moreover CIPC and Jabber are working absolutely fine for Video calls as well.

Thanks

VR

[Aaron Harrison]

Hmm.... in that case...

Are all the phones the same model?

Have you tried putting a phone in the PC VLAN rather than the voice VLAN? I'm wondering if there is some configuration different on the VVLAN traffic over the VPN/firewalls or seomthing that is causing them to flip out?

Also what are your firewalls, and do they do any SCCP inspection? Some do, and can cause problems...

[Rajan R]

No, we have 6921s, 8941s and 7937s. Its the same issue with everything. I tried SCCP and SIP with 6921s and the same issue persist. We did put the phone in PC VLAN and that didnt help either. Firewalls are ASA. and I dont think it does SCCP inspection though I have to check on them. But the CIPC were on SCCP and working fine.

Thanks

VR

[acampbell]

Hi,

You could try changing the the CUCM
service parameter Station KeepAlive Interval.

The default is 30 secs.
Try setting it 60 secs

Regards,
Alex.
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