At Asterisk's CLI, type: core show hints
This will tell you who is watching what
Verify that you've a hint in the extensions.conf file.
Example:
SPA509 has the following configuration to subscribe and monitor extension 508:
fnc=blf+sd+cp;sub=508@192.168.2.245;nme=508
The extensions.conf has the following:
exten => 508,1,Dial(SIP/508,10,rT) ;ring for 10 seconds
exten => 508,hint,SIP/508 ; hint: core show hints *CLI sees extension state
exten => 508,2,VoiceMail(508@default,u)
exten => 508,3,hangup
exten => 9508,1,VoiceMailMain(508) ;mailbox access for extension
Make sure that the sip.conf allows your phone to subscribe to extension 200's state. Continuing my example, sip.conf snippet:
; allow phone to subscribe to another phone's extension state
allowsubscribe=yes
notifyringing=yes
limitonpeer=yes
notifyhold=yes
;
Refer to the Configuring the SPA500S: https://www.myciscocommunity.com/docs/DOC-11522
<end>
