Symptom
VoIP SIP dial-peers status changes to busyout before the Router sends the Out-of-Dialog SIP OPTIONS ping. After the SIP OPTIONS message is sent, the dial-peer is back to active when the successful reply has been received. This affects the service for a small period of time depending on the delay of the reply, and it can cause the logs to get overwhelmed with 'SIP-5-DIALPEER_STATUS:' messages if the up-interval timer is too short.
Conditions
IOS higher than 15.4(1)T
VoIP SIP dial-peer with 'voice-class sip options-keepalive profile ' configured
retry count is set to 1 is the voice class sip options-keepalive profile:
voice class sip-options-keepalive 1
down-interval 10
up-interval 30
retry 1
Workaround
1. Configure the OPTIONS ping parameters directly in the dial-peer as follows:
voice-class sip options-keepalive up-interval 30 down-interval 10 retry 1
2. Increase the retry count inside the profile to 2 or higher:
voice class sip-options-keepalive 1
down-interval 10
up-interval 30
retry 2
Further Problem Description
The console logs will show first the dial-peer marked as Busied out:
%SIP-5-DIALPEER_STATUS: VoIP dial-Peer is Busied out ==> IOS Busied out the dial-peer first before even trying to send the OPTIONS ping.
%SIP-5-DIALPEER_STATUS: VoIP dial-Peer is Up ==> Once response is received it brings the dial-peer up.
