Sonicwall Tunnels were working on tz210 but not on tz400

[Kargo]

I would like to start by saying I am not the IT person for this location. Sorry if that ignorance shows. I work on the IP Office for one of our customers, and the TZ210 was swapped out for a TZ400 and now the IP Phones have not been able to connect correctly since.

What I know for sure:
They have a tunnel from router to router and the phones are configured on a LAN scheme of 192.168.55.xxx
The IP Office is on 10.10.10.xxx
I can ping a phone from the 10.10.10.xxx scheme and it responds.
I can log in an IP Phone on the 10.10.10 scheme and it registers without issue and the calls are working fine.
The 192.168.55 phones are not all logging in. 1 of them logs in reliably, however when you call it the set may answer, but the majority of the time it rings through and continues to ring and ring. Like the set never answers, and the signal to stop ringing doesn't stop.

So I know I need to work with the IT team, but I don't know what to ask them to change or what to review. The phones are not using the VPN option, as the routers handle that. Thanks for looking.

 

[DaIPOTek]

It sounds like a routing issue for sure. Can you log into the IPO from the 192.168.55.x subnet?

 

[AXCL824]

You mention a tunnel from router to router, but have only mentioned one Sonicwall being replaced. Is there multiple routers in play, or only the one Sonicwall?

If the LAN and IP Phone subnets are both physically connected to a single Sonicwall on 2 different interfaces, the Sonicwall will deal with the routing portion as long as Firewall rules are setup to allow it.

This sounds like it's an issue with software revision changes. I've seen things like this even on the same unit following a firmware update. I've even had rules that needed to be deleted and reentered identical and then started working. They (Sonicwall) appear to be getting better, but who knows how far apart the firmware revisions were when the upgraded...assuming they did an export and import into the TZ400. If not they may have just missed the rule allowing the 192. network to connect back to the 10. network on the required ports.

If you have a computer on the 192., can you ping the 10. phone system? If not, there is your issue. It sounds like the phone system can reach the phones, but the phones can't initiate a session to the system. Rule needs to be created to allow required ports from phone network to phone system network.

Sonicwall also has a few specific settings for VoIP and SIP (may not be involved) traffic. Ensure these match the old settings.

Sorry for the list of items. I'm very familiar with this setup, but without knowing the exact config it's hard. Sitting in front of it is likely a 2 min fix, hopefully their IT guys know the Sonicwall well enough to help you out.

Good Luck!