Yealink SIP-T48G Administrator's Manual page 407

Parameters
Description:
Enables or disables the IP phone to register to the secondary server when sending
requests to the secondary server in the failover mode.
0-Disabled
1-Enabled
X ranges from 1 to 16 (for SIP-T48G/T46G/T29G).
X ranges from 1 to 12 (for SIP-T42G).
X ranges from 1 to 6 (for SIP-T41P/T27P).
X ranges from 1 to 3 (for SIP-T23P/G).
X ranges from 1 to 2 (for SIP-T21(P) E2).
Web User Interface:
None
Phone User Interface:
None
To configure server redundancy for fallback purpose via web user interface:
1. Click on Account->Register.
2. Select the desired account from the pull-down list of Account.
3. Configure registration parameters of the selected account in the corresponding
fields.
Configuring Advanced Features
Permitted Values Default
393