Issue with NAT extension which has 2 possible IPs

Hi all, i hope you are all doing well.

I hope that topic title makes sense :smiley:

I’m having the following issue.

I have a SNOM phone connected behind a router that has 2 SIM cards in it , if one fails it switches to the other. From the router the SNOM phone registers as an extension on my FreePBX . that works fine no issue, however when / or if i switch the sims and thus change the IP the phone comes from it doesn’t register i can make from the phone but incoming calls don’t work.

When i look in sip show peers its shows the extension as UNKNOWN. if i wait about 30 minutes it registers on the new IP and everything works again. Sometimes if i run conntrack -D on the router it will reconnect in 10 minutes but mostly it takes 30 minutes. is there any way to fix this or could someone point me to where i can tweak the timeout settings for the extension, or in general where to look to resolve this. I’m at a bit of a loss as i don’t know where to start to isolate the issue.

thanks for any and all assistance

Hello @SkyKing,

you can use a STUN server to validate your public ip address. As for shortening the registration timeout expiration, you can reduce it on the sip account settings from 3600 seconds to 120 seconds or any other value that suits your needs.

Thank you,

Daniel Friedman
Trixton LTD.

Hi Danielf ,

Thanks for the reply , I will take a look at the above and see if it helps.

thanks again much appreciated.

The registration timeout settings defiantly helped a lot . thanks againxD much appreciated

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