Yes
I just enabled the streaming replication among 2 postgres instance and I just enabled the option wal_log_hints at the initial level of the streaming replication flow. So both master and stand by are configured with wal_log_hints as on. The streaming is going good . All the DB data replication is happening successfully.
These are the config options I have enabled in master before connecting to the slave
wal_log_hints = on
restart_command ='cp /path to the directory/%f %p'
archive_command='.......some command'
promote_trigger_file='/tmp/switch.txt'
recovery_target_timeline='latest'
After enabled the slave the same options are enabled in slave also.
Slave also running with wal_log_hints = on and all options....
Now coming to the manual fail over case I have converted the slave as master by using promote_trigger_file it was done successfully. The slave is accepting the read and write also. And now I am coverting the old master as slave for that I have done everything in new master and now by using pg_rewind I am syncing the data time lines but that command is giving the error like wal_log_hints should be in on . But I have enabled this option from beginning onwards still it is in on but in target server and source server.
On Wed, May 19, 2021 at 09:22:45PM +0530, Mohan Nagandlla wrote:
> Yes but the wal_log_hints will be in on from the begining of the server.
> Which means it is in on when I am starting the server.
Please describe more precisely the flow of what you are doing here.
It looks like what you are missing is that wal_log_hints needs to be
enabled on the target server, not the source. Please note that this
needs to be reflected in the control file of the target cluster (fetch
for "wal_log_hints setting" in the output generated by
pg_controldata).
--
Michael