Yealink SIP T2 Series Provisioning Manual page 143

Parameter
local_time.dhcp_time
auto_dst.url
Permitted
Values
represents a two-digit year.
It enables or disables the IP phone to update time
with the offset time offered by the DHCP server.
0-Disabled
0 or 1
1-Enabled
The default value is 0.
Note: It is only available to offset time from GMT 0.
It configures the access URL of the DST file
(AutoDST.xml).
Example:
auto_dst.url = tftp://192.168.1.100/AutoDST.xml
During the auto provisioning process, the IP phone
URL within 511
connects to the provisioning server
characters
"192.168.1.100", and downloads the AutoDST file
"AutoDST.xml".
The default value is blank.
Note: It works only if the value of the parameter
"local_time.summer_time" is set to 2 (Automatic).
Descriptions
Settings->Time & Date->DHCP Time
Appendix
Web Setting Path
137