VPN IP-PHONE VOIP Issue For thinkers!!!!

[jasondvox]

We use cisco for our voip. We have 3 office at home users.

Each of these 3 users have a pix 501 that connects a vpn tunnel to our concentrator (3005). I think the phones are cisco 7900 series which are connected directly to the 501's.

One of these Three little pigs experinces an issue where it seems to be every other week he cannot call (dials rings no audio) any of the 2 other little pigs but can call every one else.

Seriosly, Next week this may not be an issue and the next it may change.

I am mistified! The only think we have not done is to ask the user to move to a new town.

Help Please any direction/questions is appreciated!

 

[Sympology]

Could be a port range issue. If your are not allowing enough ports through, then it may be trying to use a RTP thta is being blocked. Are the firewall logs showing anything?

Other possible, is the ISP blocking traffic? Is there any packet loss between the two sites?

Only the truly stupid believe they know everything.
Stu.. 2004

 

[donb01]

Have you:

Swapped out the phone with another known to work?

Checked to be sure there are no other connectivity issues on the line (like the computer is offline too)?

Checked your error logs for indications of a configuration issue at your site?

Made sure it's not a bandwidth issue or you have some days/weeks with more traffic than others?

Tried using a different switch port, cables, etc in case something is flaky?

Offered the user a hearing aid? ) ok, ok... I just had to!

 

[ronromano]

I know that with other IP phones I have installed (avaya) I have had to turn off the h.323 fixups. Don't know if its the same for cisco.

 

[jasondvox]

AS for the ISP Ports. I can't imagine a phone monkey playing with the ports every other week. Who knows I have been more bord before!

As for the fix up.. Hmm would not be the first time fix up was not all that usefull.

I removed all h323 and sip type fixups.

It was mentioned something about RTP? Please do tell more about this. THere is a fixup for rtsp. Are these related?

 

[Sympology]

This may be of some help:

http://www.voip-info.org/wiki/view/NAT+and+VOIP

Only the truly stupid believe they know everything.
Stu.. 2004