Re: BDR, wal segment has been removed, is it possible move forward?

Hi Craig

On Wed, Sep 6, 2017 at 7:21 AM, Craig Ringer <craig(at)2ndquadrant(dot)com> wrote:
>
>
> BDR can, see bdr.skip_changes_upto .
>
> Unluckily my bdr is 0.9.3

> But PostgreSQL's logical decoding requires a contiguous WAL stream to
> maintain a valid catalog_xmin and restart_lsn, so it'll still fail to
> advance. So your replication from that node is broken, and you have to part
> the node then rejoin. You'll need to manually recover any diverged data.
>
> Yup, I willing to reconcile data manualy via dblink or else,
is it still possible to move wal segment in 0.9.3?

I've played these at dev env to simulate, but no luck:

# select * from pg_replication_identifier_progress;
local_id | external_id | remote_lsn | local_lsn
----------+----------------------------------------+------------+-----------
1 | bdr_6461744703437035137_1_34424_30406_ | 0/4288950 | 0/3007588
(1 row)

# SELECT
pg_replication_identifier_setup_replaying_from('bdr_6461744703437035137_1_34424_30406_');
pg_replication_identifier_setup_replaying_from
------------------------------------------------

(1 row)

# SELECT
pg_replication_identifier_setup_tx_origin('0/4288960','2017-09-06');
pg_replication_identifier_setup_tx_origin
-------------------------------------------

(1 row)

# select * from pg_replication_identifier_progress;
local_id | external_id | remote_lsn | local_lsn
----------+----------------------------------------+------------+-----------
1 | bdr_6461744703437035137_1_34424_30406_ | 0/4288950 | 0/3007588
(1 row)

--
regards

ujang jaenudin | DBA Consultant (Freelancer)
http://ora62.wordpress.com
http://id.linkedin.com/pub/ujang-jaenudin/12/64/bab