IP Hardphone over VPN stuck in Discover

[gman999]

I have an IP hardphone, connected to a home router (Draytek Vigor), which then has a VPN to our office.

The VPN is fine, I can use a laptop and ping anything.

However when using the phone, I cannot get it to go past the discover part.

I have opened

UDP 1719
TCP 1720

Any ideas?

 

[probchild]

I am having the same problem. My outside users were actually working for months before this problem occurred.

However, my problem is with Comcast cable users only. All of my Charter cable users are still running fine. Something had to have changed with Comcast around 6 to 7 months ago. I still have not resolved this issue either.

My finger is either pointing at the configuration file that Comcast downloads to their customer's cable modem or the firmware updates they have sent to the modems. I still cannot get an answer from Comcast on this issue. Nothing in our network has changed and it worked at one time. I hope you have better luck.

 

[mrjedi]

we have a similar problem. 100 shops with ADSL VPN and cisco 837s. When a site goes down and comes back up, PCs work OK but phone shows discover. Tried setting static ip address but no joy. Take the phone to the office and it works fine. Send it back to the shop and it works fine. Very strange. Looks like there is some kind of a cache that is causing this problem but I am not a data expert.

 

[probchild]

We have tried bringing the IP phones back into the office, setting them up again (making sure they connect) and sending them back to the remote site. However, ours have never reconnected.

However, I can also ping the IP phone at the remote site and send TFTP firmware updates to the phone. But again, this is only a problem with my Comcast users?

 

[nohuhu]

probchild,

discovering means that phone tries to contact gatekeeper. being in your place, the first thing i'd check would be accessibility of gatekeeper (c-lan board) ip address. plug your laptop in the phone's second ethernet interface and try to ping c-lan ip address and telnet it on the 1720 port. seems that either you or your provider has some wierd firewall settings.

 

[NX01]

I would have to agree with dwalin. The issue is most like a 1719 not open on the firewall. Do any of you do port forwarding? Once the tunnel is built on the VPN, the ISP can not see what ports you are on. So I doubt that Comcast can block it. The biggest problem we have is the network appliance running the vpn (router) needs their password to be updated. 9 times out of 10 their passwords have expired.

Just to be consistant though, you should always statically set your remote ip phones.

In the future everything will work...

 

[gman999]

Ok, now it isn't saying discovering, it says NAPT error, and lets me type in the extension, but then errors again.

I did a syslog, and is seems that everything is being sent out, but nothing is being received.

Any ideas?

 

[NX01]

You should port foward 1719 udp,1720 tcp on your vpn router at home to your ip of the hardphone. As well as the udp port range in the ip-network-region.

In the future everything will work...

 

[gman999]

I have done that, but still get the same error.

Can this work over NAT?

 

[NX01]

Did you ever get this working?

In the future everything will work...