[Spce-user] Strange error: 403 Try again later

[Jirka Jirout]

Hello,

I have (again) quite a weird issue. The server is 2.6, using our own client, TLS transport... Quite often, not always though, the client receives this reply when trying to register:

*INFO[17:18:20.541] 
SIP/2.0 403 Try again later
Via: SIP/2.0/TLS 10.0.0.5:54799;rport;branch=z9hG4bK8127795740;rport=19

I do not see any communication with the client in the kamailio logs (both lb and proxy) around this time. When I run ngrep-sip, there is no sign of the incoming packet or the reply either being passed between LB and the proxy. tcpdump does show some encrypted communication, but I have not yet looked into the contents of these packets.

Any ideas about where these strange replies can come from? What should I look for?

regards, jj