Hi,
I was going through the archives and there was a discussion about
using ini file to setup
replication.(http://www.postgresql.org/message-id/4C9876B4.9020803@enterprisedb.com).
I think if we work on this proposal and separate out the replication
setup from postgresql.conf file then we can provide more granularity
while setting up the replication parameters.
for example, we can set different values of wal_sender_timeout for
each standby sever.
So i think it is good idea to separate out the replication settings
from postgresql.conf file and put into ini file.
Once it is confirmed then we can extend the ini file to support future
developments into replication.
*for example: for failback safe standby.*
Below I have explained how to to use ini file for failback safe stadby setup:
While discussing feature of fail-back safe standby
(CAF8Q-Gy7xa60HwXc0MKajjkWFEbFDWTG=gGyu1KmT+s2xcQ-bw@mail.gmail.com)
We have decided to use the *ini* file to configure the fail-back safe standby
here is the link for that:
CAD21AoCY2_bQVPzJeY7S77amncCBXfJ+1gpHgGDbULKLAv0t+Q@mail.gmail.com
But there is no strong positive/negative feedback for the concept of
introducing the ini file.please have a look at it and give feedback.
In todays scenario, In replication we only have the 2 ways of
configuring the standby server
1. Asynchronous standby
2. Synchronous standby
With the patch of failback safe standby we have more granularity in
setting up the standby servers.
1. Default synchronous standby.(AAA)
2. Default asynchronous standby. (BBB)
3. Synchronous standby and also make same standby as a failback safe
standby.(CCC)
4. Asynchronous standby and also make same standby as a failback safe
standby.(DDD)
In failback safe standby we are thinking to add to more granular
settings of replication parameters for example
1. User can set seperate value for wal_sender_timeout for each server.
2. User can set seperate value of synchronous_transfer for each server.
Consider the scenario where user want to setup the 4 standby servers
as explained above so setting for them will be:--------- ini file -------------------------
[Server]
standby_name = 'AAA'
synchronous_transfer = commit
wal_sender_timeout = 60
[Server]
standby_name = 'BBB'
synchronous_transfer = none
wal_sender_timeout = 40
[Server]
standby_name = 'CCC'
synchronous_transfer = all
wal_sender_timeout = 50
[Server]
standby_name = 'DDD'
synchronous_transfer = data_flush
wal_sender_timeout = 50
--------------------------------------------------------
so setting up such a scenario through postgresql.conf file is
impossible and if we try to do that it will add lot of complexity to
the code.
so use of ini file will be the very good choice in this case.
Thank you ,
Samrat
