T48s won't register today

[Bob Klosinski]

Yesterday all of my 10 phones connecting through Direct Sip were working fine. Today my one T48S Won't register.
Disallow use of extension outside the LAN is disabled, and the phone was working fine yesterday, today it shows register failed in the web admin of the phone.

 

[CentrexJ]

check your ip blacklist

 

[mariosM_3CX]

Yes IP being blacklisted is definitely a reason for this.
Other possible reasons would be that multiple phones are using the same sip port at remote location
or wrong/no port forwarding on remote firewall. Check if local ip of phone has changed and adjust port forwarding rule.
You can also try resetting the phone and see if is asking extension's credentials.

 

[Bob Klosinski]

So the ip addresses are whitelisted and other phones at that location work fine. I factory reset that particular phone, and reprovisioned it and it is currently working well. However, now two other phones at the same location won't register.

 

[Bob Klosinski]

I'm using this on a google cloud instance, btw...

 

[leejor]

You have multiple sets behind a router, NOT using an SBC? Did you assign each a unique local port number as suggested by Marios? Even with that, you may have audio problems without using "PBX delivers audio" in each extensions setting. An SBC (or VPN) is highly recommended to avoid those sorts of issues.

 

[bbaker73]

Having a similar issue at a new client installation. STUN phones, ports incremented. Same as we've done at multiple other clients. Randomly, after phones working a day or so, 1-3 out of about 16 phones show no service and register failed in the webui. I have little info as I'm remotely working with a basic computer person on limited after hours time. Trying to gather info, find a rhyme or reason, rule out equipment. On one phone i was able to work with the most, rebooting did not help, reset to defaults, RPS provisioned successfully but wouldn't register. I changed the local sip port in the web ui and it registered immediately, changed back and failed. Tried two different brand routers as I assumed must be firewall issue. Even the brand I have myself and at other clients did not fix issue. Not sure if this is what I'll find with the other phones not working today or if it is a different issue.

Mostly T46S I believe, but possibly T42 as well.

This is AWS EC2 windows instance. 1 other client in same region, same type of remote STUN setup, no issues.

I know this is not helpful, hopefully I will get to the bottom of it. Driving me nuts. Doesn't help that I don't have hands on their network. PC's passing through phones network ports, no issues. Just the phones registration.

 

[leejor]

I changed the local sip port in the web ui and it registered immediately, changed back and failed.

Please explain...you changed it from what, to what?

 

[bbaker73]

Please explain...you changed it from what, to what? Each phone was, or is, assigned a unique local port number?

Yes all including this one unique, but changing it to a new unused port allowed it to register. I have 4 phones offline that I hope to be able to work on tonight and see if same issue.

 

[leejor]

As long as the existing port was not duplicated, then simply changing it should not cause it to begin registering. I would power up a set, one that was not registering. Check the 3CX Activity Log for a registration, and possible rejection. Then change the port, and check the log again. If it now registers, and the first time there was no sign of registration, and the only thing changed was the local port, then I would suspect the local router is blocking, for some reason.

Are the sets using a static IP, or DHCP? was any port forwarding, of the SIP port done in the router. Does resetting, the router (power down, then up) make a difference before the port is changed? In other words, could it be "remembering" the existing port, but have it mapped to another local IP? If you saw a registration attempt before the port change, but still no registration, perhaps 3CX is responding, but the message is going to the wrong local IP.

 

[bbaker73]

Just got off phone of 2 hours troubleshooting with remote hands. Duplicated a manual port change in web ui caused a non registered phone to register. I think we just proved it is a modem or provider issue. Rebooted modem, not router and phones that weren't working started working, but then others that had been working quit. Rebooted modem a 2nd time and right now all phones registered, again not touching the router/firewall/nat or anything other than the modem. According to remote hands, ISP provided Arris DG1670 interface is not accessible to end user. I've a feeling it's inspecting sip, as which phones connect is random. One document said this modem inspects even when in true bridge mode. Guess a call to ISP is next.

 

[bbaker73]

Also, I was short on time for troubleshooting, but in verbose, I did see some session timeouts, mostly didn't see any attempt for the phone to register.

So their phones are working right now. How long can I leave it in verbose without causing issues? I don't want to restart services and risk all the phones not connecting as my remote hands are gone. 17 phones on a 2 core 4GB windows server.

 

[leejor]

Obviously the modem/router combo isn't behaving simply as a modem, it's affecting traffic. Perhaps your ISP, if that is who supplied the device, has a way to "remove" anything but the modem function.

I wouldn't eave 3CX in Verbose forever, but, unless you are limited in disk space, you should be good for a while. Check, in a few days to see how much space is still available.