Keep alive messages with 797X phones issues anyone?

Unanswered Question
Jan 22nd, 2010

we recently upgraded from 6.x to 7.1.3 and then upgraded the 797X phones firmware to the latest images.   After the phones upgraded, they would not register to cucm if they were remote.  Locally on the LAN, it was fine.   The phones were online at the remote site, trying to register to CUCM, but would fail, then go the SUB, then SRST and keep cycling over and over.  We ended up backing down the firm two versions and the phones were fine then.

Id say this is ok, but we now have 7975 phones and 7916 expansion  modules.  They require the latest firmware to work.   I have a TAC case open but was wonderin if anyone else has had issues.


  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
prolival Wed, 05/26/2010 - 08:41

Hello tcatlinins,

I have exactly the same problem you described in this topic.

We have tried to upgrade to version 7.1.3 but we had to rollback as the remote phones were unable to register.

There was no problem for local phones like you said in the description of your problem.

Did you find a solution for your problem? I am very interested of your feedback as it is a real blocking problem for us.

Thanks in advance.

Tommer Catlin Wed, 05/26/2010 - 09:09

They had a netscreen firewall inbetween the remote site and CUCM.   We ended up finding a command line for the firewall  "unset alg sccp enable"

and that fixed it.   We never needed it before, but after this firmware for the phones, it was required.  odd.

prolival Fri, 05/28/2010 - 09:24

Thanks for your quick response.

I will check with my customer if such devices can cause our problem.


This Discussion