Solved SIPS inbound from flowroute stopped working

[AlexanderReichert]

Since last night the inbound traffic from Flowroute to 3CX stopped working on SIPS port 5061.
After lengthy troubleshooting I finally find this in the capture trace.



147.75.60.160 is Flowroute
10.100.0.10 is 3CX
I am only not sure which certificate is expired? I checked the certificate that I can find in 3CX under Security -> Secure SIP and that one is not expired. still valid until 12/16/2021

 

[cmp1]

Might be that LE root cert that expired.
We had to remove the ISRG Root X1 cert from TLS section to get Polycom phones to work properly.
Could also be that Flowroute's servers have update LE root certs... those expired today.

 

[AlexanderReichert]

I am not sure where you had to remove said root cert ....
you you explain in more detail please

 

[cmp1]

Under Security -> Secure SIP - go copy each of the 3 cert individually, and decode... but it should be the LAST Certificate.

Decoder:
https://certlogik.com/decoder/

Delete that cert, and reload services.

You're looking for this one..

Certificate Summary​

Subject​

RDN	Value
Common Name (CN)	ISRG Root X1
Organization (O)	Internet Security Research Group
Country (C)	US

 

[AlexanderReichert]

perfect! thank you so much for the hint. that did the trick - now SIPS is working again ...

 

[YiannisH_3CX]

Glad to see the issue has been resolved. Just an FYI here, we do not support mutual TLS authentication which is what Flowroute is using so you might have other issues in the future so I would not recommend using Flowroute with TLS just yet.