When the IP phone registers to the sip server, if the main sip server is down, you can back up it to the other ip server.
the setting is like this:
1. we will input the related information like this:
Here the account and password of two sip server need to be same, and their server address and sip port can be different.
the related information of the main sip server is like this:
sip server address: 192.168.1.43
sip port: 5060
the related information of back up sip server is like this:
sip server address: 192.168.1.47
sip port: 6620
2. let us change the registration expires from 3600 to 60, when the main sip server is down, the phone will switch to the back up server soon.
3. if the sip server is ok again, the phone needs to switch to the main sip server, at present, we need to change one parameter in the config file.
please change the parameter SIP1 Enable Failbac as 1, and then save it.
After that, we need to upload the file to the phone.
that is all the settings.