Grandstream Networks GRP261X Administration Manual page 44

DNS SRV Fail-over
Mode
Register Before DNS
SRV Failover
Primary IP
Backup IP 1
Backup IP 2
If the user wishes to locate the server by DNS SRV, the user may select
"SRV" or "NATPTR/SRV".
If "Use Configured IP" is selected, please fill in the three fields below:

Primary IP

Backup IP 1

Backup IP 2
If SIP server is configured as domain name, phone will not send DNS query,
but use "Primary IP" or "Backup IP x" to send SIP message if at least one of
them are not empty.
Phone will try to use "Primary IP" first. After 3 tries without any response, it
will switch to "Backup IP x", and then it will switch back to "Primary IP" after
3 re-tries.
If SIP server is already an IP address, phone will use it directly even "User
Configured IP" is selected.
The option will decide which IP is going to be used in sending SIP packets
after IPs for SIP server host are resolved with DNS SRV.

Default
If the option is set with "default", it will again try to send register messages to
one IP at a time, and the process repeats.

Saved one until DNS TTL
If the option is set with "Saved one until DNS TTL", it will send register
messages to the previously registered IP first. If no response, it will try to
send one at a time for each IP. This behavior lasts if DNS TTL (time-to-live)
is up.

Saved one until no responses
If the option is set with "Saved one until no responses", it will send register
messages to the previously registered IP first, but this behavior will persist
until the registered server does not respond.
Indicates whether a REGISTER request will be initiated when a server
failover occurred under DNS SRV mode.
Default setting is No.
Configures the primary IP address where the phone sends DNS query to
when "Use Configured IP" is selected for DNS mode.
Configures the backup IP1 address where the phone sends DNS query to
when "Use Configured IP" is selected for DNS mode.
Configures the backup IP2 address where the phone sends DNS query to
when "Use Configured IP" is selected for DNS mode.
GRP261x/GRP2624/GRP2634 Administration Guide
Version 1.0.5.48
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