TIPS Extensions unregistering randomly

[rjm]

I have an issue I just can seem to get my head around, nor can some of the brightest minds I know, so I am reaching out to the hive mind to see if anyone else has ever seen anything like this.

The symptom is that my extensions are dropping registration about once a day. Usually after some period of not being used, but this is not always the case.

I have a Rent PBX server in the cloud, and extensions in three locations on four different ip addresses. One common thread is that 95% of the extensions are on Comcast internet service. Maybe 1 is not, but I don't know for sure.

Here's what's under the hood:

PIAF Installed Version = 2.0.6.4 under *XEN* on Rent PBX
FreePBX Version = 2.11.0.41
Running Asterisk Version = 11.5.1
Asterisk Source Version = 11.5.1
Dahdi Source Version = 2.7.0.1
Libpri Source Version = 1.4.14
IP Address = 108.61.45.149 on eth0
Operating System = CentOS release 6.4 (Final)
Kernel Version = 2.6.32-358.6.2.el6.i686 - 32 Bit

My Asterisk Sip Settings are NAT=Yes and IP Configuration=Public. I've got my pbx extension settings set up as NAT=Yes, qualify=yes, qualify frequency=15. The phones are Grandstream GXV3240's with are set up as NAT=Auto and GXP2200's with NAT=Keep Alive.

I have been playing with extension setting relating to nat, server settings and the like, but to no consistent results. I also diddled with the phone nat settings. Same thing.

Then I noticed something very odd. When I reset my server, everything comes back. All the extensions. So I thought I had bad NAT settings on the server side that didn't set up properly until a reboot. But after a few hours, I lost some of the extensions again.

Another reset, all the extensions except for two came back. Eventually, after an hour or more, they also registered. And again, after a few more hours, half the extensions dropped registration again.

So I am thinking something network on the server side. So thinking I would like to be sure of that, I tried to service asterisk restart, figuring that if the extensions didn't register but did with a reboot, that it is definitely network related. But they DID reregister after restarting Asterisk!

Now I am really stumped. Can anyone think of any reason I am seeing this?

Watching cli I noticed one consistent symptom is that the extensions will lose registration after substantial lagging (3000+ ms). This happens across all three locations, all with different network/router configurations.

So I guess I have four questions:

1. Why would I get this kind of random lagging issue?
2. Why would the extensions fail to re-register after dropping off?
3. Why do all the extensions re-register after restarting Asterisk?
4. How can I fix it?

Thank you for your ideas!

Rob

Rob

 

[dad311]

From your RentPBX account, try running mtr ( mtr <remote ip >. I had a customer on comcast that was dropping 14% of the packets from the PBX to the phones, the phones were lagging, dropping registrations, choppy audio, etc.

 

[rjm]

Thanks dad311! I'll do it.

The trouble is that I have three different locations, all with the same issues. And the server is on a fourth. On the other hand, I know for a fact that one location had comcast issues. It is my home connection and it was down for three hours yesterday.

 

[rjm]

So I am getting some long lag times. I guess that is the main issue, but I still have the question of why don't the phones re-register once they have dropped registration? Shouldn't they keep trying?

 

[briankelly63]

Depending on how they are "set" there is usually a parameter on the telephone set that controls that re-registration timeline.

 

[rjm]

That is true and thanks for the comment. The problem is that with a long or persistent lag, the phone drops registration and stops trying. I can't figure out why it stops trying.

 

[rjm]

If you read this far, here is the end of the story: http://pbxinaflash.com/community/index.php?threads/registration-vs-reachable-issues.16080/