Subscriber Absent

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Hi all

WE have some users that turns off their phones when they are not at home.

We see the warning message:

Unable to create channel of type ‘SIP’ (cause 20 – Subscriber absent)

just after the Dial() command and a

Everyone is busy/congested at this time


Where is this “unable – cause 20” status available in the dialplan?
Which variable holds this?

We’d like to play something to the caller in case the user is absent.



One thought on - Subscriber Absent

  • This means the SIP endpoint is defined in sip.conf, but no device is registered; which is consistent with phones being turned off.

    It should be ${HANGUPCAUSE} . So you can use something like

    Gotoif($[${HANGUPCAUSE} ]?subs_absent)

    in your dialplan, and it will go to the label (subs_absent) if the Dial()
    fails for “cause 20 – Subscriber Absent”. Then you can play a recorded announcement, or send them to voicemail.