PgBackRest : Restore to a checkpoint shows further transactions

From: KK CHN <kkchn(dot)in(at)gmail(dot)com>
To: pgsql-general <pgsql-general(at)postgresql(dot)org>
Subject: PgBackRest : Restore to a checkpoint shows further transactions
Date: 2024-09-25 06:12:58
Message-ID: CAKgGyB_UaN7a5Pe9ea2e5at7LLrypYEQit=XmWc_SKXnHWpjdg@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

List,

PgBackRest : I tried to restore the latest backup taken at my RepoServer
to a testing EPAS server freshly deployed .

I have a full backup, two diff and one INCR as on today morning. The
latest one is INCR

full backup: 20240922-232733F
timestamp start/stop: 2024-09-22 23:27:33+05:30 / 2024-09-23
09:17:00+05:30

diff backup: 20240922-232733F_20240924-222336D
timestamp start/stop: 2024-09-24 22:23:36+05:30 / 2024-09-24
22:55:41+05:30

incr backup: 20240922-232733F_20240925-082637I
timestamp start/stop: 2024-09-25 08:26:37+05:30 / 2024-09-25
08:36:00+05:30

On my Test EPAS Server :

[root(at)dbch ~]# *sudo -u enterprisedb pgbackrest --stanza=Repo1 --delta
--set=20240922-232733F_20240925-082637*I --target-timeline=current
*restore*

2024-09-25 10:28:42.493 P00 INFO: restore command end: completed
successfully (2657236ms)

Now I comment out the archive command in the test EPAS server
postgresql.conf and started the EPAS server.

WHen I issue a query to select few rows To my surprise I am seeing the
records with columns with time stamp up to a time 10.36:11:968 and 1
0:36:13.363 :

How did this happen ? I specified the restore point file (incr) taken at
2024-09-25 08:26:37, naturally I expected restore may show records up
to this time stamp or up to 2024-09-25 08:36:00+05:30 but it shows
further to 10.36:11:968 and 0:36:13.363 but not beyond this !!!

But my restore ends successfully at 2024-09-25 10:28:42.493 P00 INFO:
restore command end: completed successfully (2657236ms)

Could someone explain how this comes about ?

But no other records latest than 10.36:11:968 and 0:36:13.363
showing .. How is it delimited here at this time stamp ?

SO I guess this is due to specifying --target-timeline=current ? But
restore finished at 10.28:42.493

OR

Does this take all wal and replay up to the EPAS service starting time
of the testing EPAS server ?

Thank you,

Krishane.

For more inputs : I have queried like this below..

t_db=# select * from c.cti_all_info ORDER BY received_time DESC LIMIT 1;
id | caller_number | call_identifier | ivr_start_time |
ivr_connect_time | ivr_drop_time | ivr_drop_reason | call_landing_time |
call_start_time | call_end_time | call_drop_reason
| sip_extension | call_direction |

message_list

| voice_path | partition_key | received_time
| remarks | source_ip_address | pilot_number
---------+---------------+--------------------+-------------------------+------------------+---------------+-----------------+-------------------+-----------------+-------------------------+-------------------
+---------------+----------------------------------------------------------------------------------------------------------------------------+------------+---------------+----------------------
---+---------+-------------------+--------------
66769044 | 555657643942 | 140771.5140 | 2024-09-25 10:36:11.968 |
| | | |
| 2024-09-25 10:36:13.363 | User Disconnected
| | IN | ["{\"srcType\":\"ACS\",\"srId\":\"

I have PgBack successfully running on a Production Server and a Repo
Server RHEL9.4, PgBackRest 2.52.1 and EPAS 16.1 . Restore performing for
the first time.

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Paul Foerster 2024-09-25 07:16:20 Re: glibc updarte 2.31 to 2.38
Previous Message Danish Hajwane 2024-09-25 05:27:10 MError after replication in postgresql