SBC stuck in a fail loop

[nhathaway]

CRIT | 20240812-152638.513 | 3CX | SBC | 0xffff8e740020 | Log.cpp:159 | ====================== 3CX SmartSBC 20.0.100 @xxx.xxx.xxx.co.uk ======================
CRIT | 20240812-152638.513 | 3CX | SBC | 0xffff8e740020 | Log.cpp:160 | Log started: type = file, level = ERR, size = 104857600, resip = ERR, remote = -1
CRIT | 20240812-152638.521 | 3CX | SBC | 0xffff8e740020 | Bridge.cpp:28 | System Clock: resolution 0 microseconds, not monotonic
ERR | 20240812-152638.530 | 3CX | RESIP | 0xffff8e740020 | /home/repomaster/workspace/SBC/resiprocate/resip/stack/ssl/Security.cxx:526 | is empty. Skipping.
CRIT | 20240812-152638.542 | 3CX | SBC | 0xffff8e740020 | RPiTunnel.cpp:412 | Running in console mode
ERR | 20240812-152638.552 | 3CX | SBC | 0xffff8e740020 | TunnelTcp.cpp:621 | SSL error (104):
ERR | 20240812-152638.552 | 3CX | SBC | 0xffff8e740020 | TunnelTcp.cpp:305 | Bridge failure on while begin to read a packet from tunnel: Connection reset by peer
ERR | 20240812-152644.579 | 3CX | SBC | 0xffff8e740020 | TunnelTcp.cpp:621 | SSL error (104):
ERR | 20240812-152644.580 | 3CX | SBC | 0xffff8e740020 | TunnelTcp.cpp:305 | Bridge failure on while sending: Connection reset by peer
ERR | 20240812-152644.580 | 3CX | SBC | 0xffff8e740020 | TunnelTcp.cpp:605 | It is not possible to establish (optional) secure connection. Fallback to unsecured tunnel.
ERR | 20240812-152650.604 | 3CX | SBC | 0xffff8e740020 | TunnelTcp.cpp:621 | SSL error (104):
ERR | 20240812-152650.604 | 3CX | SBC | 0xffff8e740020 | TunnelTcp.cpp:305 | Bridge failure on while sending: Connection reset by peer
ERR | 20240812-152650.605 | 3CX | SBC | 0xffff8e740020 | TunnelTcp.cpp:605 | It is not possible to establish (optional) secure connection. Fallback to unsecured tunnel.
CRIT | 20240812-152656.617 | 3CX | SBC | 0xffff8e740020 | RPiTunnel.cpp:429 | Stopping: Maximum number of connection attempts reached
CRIT | 20240812-152657.055 | 3CX | SBC | 0xffff8e740020 | RPiTunnel.cpp:424 | ** Main console thread exits.

Any idea how to fix this?

 

[Evolute IT]

IP conflict?

 

[nhathaway]

IP conflict?

No

 

[CentrexJ]

Is this a desk phone or SBC software running on a pc/vm?

If its on a desk phone, we have seen this with Yealink T54W desk phones (likely others) when the site has dual wan configuration.

If its pc or vm we have not seen this, we put it on a pc or vm for locations that have dual wan.

 

[nhathaway]

It's running on a Raspberry Pi. It has dual NIC, plus other connections, e.g. openVPN, Wireguard and Docker (it is a router/server). It's running direct on the Pi, not inside Docker.

 

[Guillaume Bourgeois]

It's running on a Raspberry Pi. It has dual NIC, plus other connections, e.g. openVPN, Wireguard and Docker (it is a router/server). It's running direct on the Pi, not inside Docker.

You mentioned that the 3CX SBC service is running on the same environment as OpenVPN, Wireguard, and Docker?

If so, you've identified the cause of your issue. Running the 3CX SBC service alongside OpenVPN, Wireguard, and Docker is likely the problem.

These services are known to cause disruptions.

Does the VPN allow communication with the phone system using its local IP address?
If so, uninstall the SBC service and rely solely on the VPN. Make sure the phones are configured to use this tunnel.
As long as the VPN server isn't the 3CX PBX...


Otherwise, uninstall the VPN services and use the 3CX SBC service instead.
However, please don't attempt to run both, even if you have two network cards!

With some effort, you might be able to get both working, but I guarantee you'll face plenty of issues down the line!

 

[nhathaway]

Maybe I should run it inside Docker, where the environment is simpler and more controllable.

I am using the Free version of 3CX as a replacement for Asterisk + FreePBX, which I have got tired of updating every couple of years. However, if 3CX is so difficult to get working, then I may switch back. I certainly can't switch off the VPN links to other offices I have connections to.

 

[Guillaume Bourgeois]

[...] if 3CX is so difficult to get working, then I may switch back. [...]

No, it’s not difficult; you’re making your setup complicated.
Keep it simple! Go back to basics.
3CX is designed to be reliable, fast, easy, and straightforward.

Get a dedicated Pi for the 3CX SBC, and that will solve your problem.

Or get a phone with built-in SBC functionality.
https://www.3cx.com/blog/docs/sbc-router-phone/

I am using the Free version of 3CX as a replacement for Asterisk + FreePBX, which I have got tired of updating every couple of years.

When you say "Free," you're referring to the SMB Free version, correct?
https://www.3cx.com/blog/releases/smb-phone-system/

If so, you have the right product—3CX takes care of the updates for you!

 

[nhathaway]

It changed, and now it is doing this:

ERR | 20240812-234502.444 | 3CX | SBC | 0xffffa8132020 | BridgeTunSip.cpp:22 |
** Resip exception caught while processing SIP message from Tunnel
! Exception: Drop invalid 2543 response

ERR | 20240812-234527.093 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-234625.974 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-234725.174 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-234825.186 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-234925.485 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-235024.434 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-235121.691 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-235220.693 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-235319.100 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-235417.539 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-235515.925 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-235614.965 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-235713.979 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-235812.881 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240812-235912.542 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240813-000011.593 | 3CX | SBC | 0xffffa6387060 | CallSession.cpp:559 | 9d532d76f950af65dfcc73f0293b1702 Current Offer/Answer state is LOffer; expected - Idle
ERR | 20240813-004910.959 | 3CX | SBC | 0xffffa8132020 | BridgeTunSip.cpp:22 |
** Resip exception caught while processing SIP message from Tunnel
! Exception: Drop invalid 2543 response

 

[nhathaway]

I have closed off SIP ports 5060 and 5061 in the firewall to the Internet and now the SIP error messages have stopped.

So, basically the problem fixed itself just before midnight without my intervention. The SBC has a green blob on the 3CX web console now.

One further question: I would like to specify the local IP address for SIP, rather than auto (0.0.0.0). However, any changes I make to /etc/3cxsbc.conf immediately revert when I start up the SBC. Is there any way to fix this?

 

[Guillaume Bourgeois]

@nhathaway

You haven't solved your problem!

I clearly explained that you will encounter multiple issues with your non-compliant installation over time. Naturally, when you do encounter problems, you will complain that 3CX is not stable!

If you need to manually make a modification in the SBC, it means you are not compliant.

If you are too frugal to buy a new Raspberry Pi dedicated for 3CX SBC, you don't deserve my help.

Good luck.