Yealink SIP T46G Administrator's Manual page 167

Administrator's Guide for SIP-T46G IP Phone
the call:
1. Send the INVITE request to the primary server.
2. If the primary server does not respond correctly to the INVITE, then try and make
the call using the secondary server.
3. If the secondary server is also unavailable, the IP phone will try the fallback server
until it either succeeds in making a call or exhausts all servers at which point the
call will fail.
At the start of a call, server availability is determined by SIP signaling failure. SIP
signaling failure depends on the SIP protocol being used as described below:
If TCP is used, then the signaling fails if the connection fails or the Send fails.

If UDP is used, then the signaling fails if ICMP is detected or if the signal times out. If

the signaling has been attempted through all servers in the list and this is the last
server, then the signaling fails after the complete UDP timeout defined in RFC 3261.
If it is not the last server in the list, the maximum number of retries depends on the
configured retry count.
Procedure
Server redundancy can be configured using the configuration files or locally.
Configuration File
Local
To configure the server redundancy via web user interface:
1. Click on Account.
2. Select the desired account from the pull-down list of Account.
3. Select the desired value from the pull-down list of Transport.
4. Configure parameters of the SIP server 1 in the corresponding fields.
154
<MAC>.cfg
Web User Interface
Configure the server
redundancy on the IP phone.
For more information, refer to
Server Redundancy on page
311.
Configure the server
redundancy on the IP phone.
Navigate to:
http://<phoneIPAddress>/servl
et?p=account-register&q=load
&acc=0