Server Redundancy - Yealink SIP-T2XP Administrator's Manual

2. Select the desired value from the pull-down list of Reboot In Talking.
3. Click Confirm to accept the change.

Server Redundancy

Server redundancy is often required in VoIP deployments to ensure continuity of phone
service, for events where the server needs to be taken offline for maintenance, the
server fails, or the connection between the IP phone and the server fails.
Two types of redundancy are possible. In some cases, a combination of the two may
be deployed:
Failover: In this mode, the full phone system functionality is preserved by having a

second equivalent capability call server take over from the one that has gone
down/off-line. This mode of operation should be done using the DNS mechanism
from the primary to the secondary server.
Fallback: In this mode, a second less featured call server with SIP capability takes

over call control to provide basic calling capability, but without some advanced
features offered by the working server (for example, shared line, call recording
and MWI). IP phones support configuration of two SIP servers per SIP registration for
fallback purpose.
Phone Configuration for Redundancy Implementation
To assist in explaining the redundancy behavior, an illustrative example of how an IP
phone may be configured is shown next. In the example, server redundancy for
fallback and failover purposes is deployed. Two separate SIP servers (a working server
Features
Configuring Advanced
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