group set leader v5.6
Switches a group over to new write leader
Synopsis
Switches over to new write leader. Use the method fast
for immediate
switchover. Use strict
to wait until lag is less than route_writer_max_lag
on the given target node. If switchover fails due to timeout or any other
issue, BDR might elect a write leader that's different from the given target
node.
pgd group set leader [flags]
Options
Flag | Flag, long | Value | Description |
---|---|---|---|
--group-name | groupname | group name of group where write leader will change | |
--node-name | nodename | node name of proposed new write leader | |
--method | strict | fast | switchover method. Default strict | |
--timeout | duration | timeout period when switchover method is strict. Default 10s |
Switchover methods
strict
- waits until lag on given node is less thanroute_writer_max_lag
(default).fast
- immediate switchover,route_writer_max_lag
is ignored.
Examples
With defaults
In this example, we use the option defaults. This means the method defaults to strict
and uses the default 10s
timeout.
$ pgd group set leader --group-name group_a --node-name bdr-a1
Output
switchover is complete
With options
In this example, we explicitly use the strict
method but set the timeout to 15s
.
$ pgd group set leader --group-name group_a --node-name bdr-a1 --method strict --timeout 15s
Output
switchover is complete
Immediate switchover
In this example, we use the fast
method for immediate switchover.
$ pgd group set leader --group-name group_a --node-name bdr-a1 --method fast
Output
switchover is complete