SIP Trunk Keeps Getting Deregistered — Help Appreciated

smb_user_au

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Hi everyone,

I’m fairly new to 3CX and would really appreciate some guidance from the community.

I’m running into an issue where my SIP trunk keeps getting deregistered intermittently. The event log consistently shows this message:

"Trunk has changed status to unregistered. This means no more calls will pass via the trunk. Please check your network connection and the VoIP provider or other SIP PBX."

I'm using an authorized, certified SIP provider for Australia.

This has happened 3 or 4 times over the past few weeks. In most cases, simply clicking “Refresh Registration” in the management console turns the trunk status from red to green, and calls start working again. But this time, even after refreshing, the trunk remains unregistered and I can't make or receive calls.

Everything else on my network appears to be working fine. I’ve checked my SIP trunk settings and internet connection.

Has anyone else faced something similar? Any pointers on what logs or settings I should dig into? Would be grateful for any help or troubleshooting tips.

Thanks in advance!
 
Hi, can you clarify briefly a bit more about your setup, ie,

3cx version (Pro 8SC, other?)
hosted in your LAN / close to phone handsets? Hosted 'in cloud' with public IP for 3cx / and your lan phones talk to 3cx via SBC in office LAN? something else ? (ie, clients are smartphone app - or computer softphone app - no SBC?)
hosted on dedicated hardware vs inside a VM on a known / good / supported (ie by you/your team) Hypervisor?
no known drama for hardware or hypervisor is known/possible for place where 3cx lives ?

the only cases where I've regularly seen flapping on trunk / connection status for 3cx instances is normally limited to
(a) SBC connecting to 3cx in cloud <> flips intermittently if the NIC on the SBC hardware is flakey / poor driver support in linux (ie, specific versions of e1000 nic are not great it seems sometimes for example) - but often all this shows up as - is brief intermittent down-up warn messages - things tend to 'keep working most of the time' - just an abundance of annoying down-up warn messages every few days maybe. So long as SBC/phones are dormant when 'mini outage' happens - nobody notices. Arguably this is poor baseline and such hardware is a great candidate to remove-replace

(b) other flakey network issues? you seem to have ruled that out already?

(c) provider has some intermittent issues? Triple-checked the config for your SIP trunk / make sure expire setting is ok (ie, not too long not too short?) Have you opened a support ticket with your SIP Trunk provider and asked specifically with some precise time-date examples of flapping / outage / in case their team can help you dig in and give you feedback? (ie, such as "Oh yeah we had a DDOS at that date-time on our server, and service was a bit delicate, so yeah that one is on us". for example.)

not sure this is helpful really but possibly a start / and maybe others can chime in any thoughts-suggestions.

Tim
 

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