3CX isn't replying to SIP OPTIONS.

[mastermindjf]

Today, the system stopped being able to make or receive calls. After opening a ticket with a provider in Brazil called CLARO, I received the following response:

"Your system isn’t replying to SIP OPTIONS packets."

After checking the logs, I can confirm that many OPTIONS packets are being received by the 3CX server.


My question is: Does 3CX reply to OPTIONS packets? If so, where can I configure this?

 

[paulodagraca]

Hello @mastermindjf,

Have you done a capture on the 3CX to confirm this happening?
Meaning the 3CX does receive it and no responce is given on packet base.

Meaning one side not receiving does not always mean the other side is not sending. Could be lost in network.

Paulo

 

[YiannisH_3CX]

My question is: Does 3CX reply to OPTIONS packets? If so, where can I configure this?

3CX replies to SIP OPTIONS by default. No need to configure anything. I suspect your providers IP may be blacklisted. Check the IP Blacklist by navigating to Advanced --> IP Blacklist and make your your providers IP is not listed there. You could also whitelist it to make sure.

 

[paulodagraca]

Hello mastermindjf,

Please do check the 3CX blacklist as mentioned by YiannisH_3CX.
However it could be something else, like... (some examples)

-The Firewall does have the SIP ALG set ON, please disable if so.
-Firewall has UDP timeout shorter than 30 seconds or shorter than Provider timeout, please change KEEPALIVE_TIME_UDP to 15 sec.
-Check IP adres of the SIP OPTIONS, could be another IP than the SIP register IP, (if multiple servers active). and update firewall and blacklist.

Hope this will help you with finding the sollution for your problem.

Paulo

 

[mastermindjf]

Hello @mastermindjf,

Have you done a capture on the 3CX to confirm this happening?
Meaning the 3CX does receive it and no responce is given on packet base.

Meaning one side not receiving does not always mean the other side is not sending. Could be lost in network.

Paulo

Thank you for your response. The SIP OPTION packets were reaching the interface, but 3CX wasn’t replying initially. After performing two reboots, the system started responding correctly. No errors were found in the logs, which makes this behavior quite unusual.

 

[mastermindjf]

3CX replies to SIP OPTIONS by default. No need to configure anything. I suspect your providers IP may be blacklisted. Check the IP Blacklist by navigating to Advanced --> IP Blacklist and make your your providers IP is not listed there. You could also whitelist it to make sure.

Thank you for your reply. I found a lot of information online, though many older references mention that 3CX does not respond to OPTIONS packets. Now i know.
Thanks

 

[mastermindjf]

Problem solved after correct information.

Thank you all.

 

[osti.carvalho]

Problem solved after correct information.

Thank you all.

Good afternoon Mastermindjf.

How did you manage to solve the problem? I'm having the same issue here.

 

[edossantos_sipcaller]

Good afternoon Mastermindjf.

How did you manage to solve the problem? I'm having the same issue here.

He mentioned that rebooted the 3CX server. Probably a firewall issue....