Re: How to get current timeline of host in postgres 10.4?

[Rui DeSousa <rui.desousa@xxxxxxxxxx>]

Shreeyansh,

Given the LSN you can get the filename which has the timeline encoded in it.

(Can only get the filename on master)

> select substring(pg_walfile_name(pg_current_wal_lsn()), 1, 8);

 substring 

-----------

 00000002

Other options (works on both master/slave):

# pg_control_data | grep -i TimeLine

Or 

Just use the same method on the you used on slave on the master.

psql -h "localhost" -F' ' -c 'IDENTIFY_SYSTEM' 'dbname=replication replication=true' -U postgres

On Jun 15, 2018, at 12:41 PM, Debraj Manna <subharaj.manna@xxxxxxxxx> wrote:

Hi Shreeyansh

I have executed the below query on master. But it is giving output like below

postgres=# select pg_current_wal_lsn();

 pg_current_wal_lsn

--------------------

 0/4B17D198

(1 row)

In slave side it is saying timeline 6

ubuntu@platform1:~$ psql -h "localhost" -F' ' -c 'IDENTIFY_SYSTEM' 'dbname=replication replication=true' -U postgres

      systemid       | timeline |  xlogpos   | dbname

---------------------+----------+------------+--------

 6567260231287314481 |        6 | 0/4B1786E0 |

How can I get the timeline from the output of the query in master?

On Fri, Jun 15, 2018 at 9:57 PM, Shreeyansh Dba <shreeyansh2014@xxxxxxxxx> wrote:

Hi Debraj,

Execute below query on Master Side :
select pg_current_wal_lsn();
Execute below query on Slave Side:
using replication protocol (example from version 10.4)
psql -h "$host" -F' ' -c 'IDENTIFY_SYSTEM' 'dbname=replication replication=true'

Hope it helps.

On Fri, Jun 15, 2018 at 9:35 PM, Debraj Manna <subharaj.manna@xxxxxxxxx> wrote:

HI

Can someone let me know what is the best way to get current timeline of host (in both master and the slaves) in postgres 10.4?

Thanks,