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SIP response codes

SIP 600 Busy Everywhere

Busy Everywhere: the user is busy on all devices and does not want another call.

600
Name
Busy Everywhere
Class
6xx · Global failure
Defined in
RFC 3261
Q.850 cause towards the PSTN
17 · User busy

When it happens

  • Every registered device of the user is busy or the user set "busy" status.

What to check

  • Nothing to fix; try later.

What the response looks like

SIP/2.0 600 Busy Everywhere
Via: SIP/2.0/UDP 203.0.113.10:5060;branch=z9hG4bK776asdhds
From: <sip:101@pbx.example>;tag=1928301774
To: <sip:+15551234567@pbx.example>;tag=a6c85cf
Call-ID: a84b4c76e66710@203.0.113.10
CSeq: 2 INVITE
Reason: Q.850;cause=17;text="User busy"
Content-Length: 0

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