Yealink SIP-T2 SERIES Administrator's Manual page 947

The web user interface prompts the message ―Are you sure delete user-defined
factory configuration?‖.
3. Click OK to delete the custom factory configuration files.
The imported custom factory file will be deleted. The IP phone will be reset to
default factory configurations after resetting.
IP phones support remote reboot by a SIP NOTIFY message with ―Event: check-sync‖
header. Whether the IP phone reboots or not depends on the value of the parameter
―sip.notify_reboot_enable‖. If the value is set to 1, or the value is set to 0 and the header
of the SIP NOTIFY message contains an additional string ―reboot=true‖, the IP phone
will reboot immediately.
The NOTIFY message is formed as shown:
NOTIFY sip:<user>@<dsthost> SIP/2.0
To: sip:<user>@<dsthost>
From: sip:sipsak@<srchost>
CSeq: 10 NOTIFY
Call-ID: 1234@<srchost>
Event: check-sync;reboot=true
Troubleshooting
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