Re: repmgr cannot bring up the standby database after switchover manaully

Hello Fernando,

In my recent experience, there was no issue starting the old primary—it
came up normally. However, it resulted in a split-brain situation where the
old primary continued to accept both read and write operations while still
assuming the other two nodes were replicas.

This issue occurred with the following environment:

-

*OS version:* RHEL 8.10
-

*Postgres DB version:* 14.9
-

*repmgr version:* 5.5.0

Tayyab

On Wed, Oct 1, 2025 at 11:52 AM Fernando Hevia <fhevia(at)gmail(dot)com> wrote:

>
> I have 2 postgresql servers. One is the primary and another one is the
>> standby. I am trying to setup repmgr to do the switchover manually.
>> Passwordless ssh have been setup for postgres ID on both servers.
>>
>> I use this command "repmgr standby switchover --log-level=DEBUG
>> --verbose". The standy database is able to promote to be the primary. For
>> the previous primary database, it was shutdown. It was not able to bring up
>> as standby by repmgr.
>
>
> In a switchover the primary server is shutdown and restarted as a standby
> server after the newly promoted primary (former secondary) node has been
> started.
> If the primary did not start, there must have been an issue since this is
> not the standard behavior for a switchover command.
>
> Have you checked the Postgres log file for the previous primary? You
> should find the startup failure cause in the log.
>
> Regards,
> Fernando
>
>
>
> El mié, 1 oct 2025 a la(s) 7:30 a.m., Chris Lee (clee(dot)hk(at)gmail(dot)com)
> escribió:
>
>> Hi Tayyab,
>>
>> Thanks for your information . I also want to find out whether that is the
>> default behavior, or I am not configuring repmgr correctly.
>>
>> Regards,
>> Chris
>>
>> On Wed, 1 Oct 2025, 18:12 Imran Khan, <imran(dot)k(dot)23(at)gmail(dot)com> wrote:
>>
>>> Hi Tayyab,
>>>
>>> Is this a default behavior? We have 4 nodes cluster but never had issue
>>> in switchovers.
>>>
>>> Thanks,
>>> Imran
>>>
>>> On Wed, Oct 1, 2025, 1:10 PM Tayyab Fayyaz <tayyab(dot)humayl(at)gmail(dot)com>
>>> wrote:
>>>
>>>> Hello Chris,
>>>>
>>>> I faced this issue it will not add automatically as standby you have to
>>>> add it manually.
>>>>
>>>> But I wrote a script which perform to add old primary as standby once
>>>> it's back online.
>>>>
>>>> Tayyab
>>>>
>>>>
>>>> On Wed, 1 Oct 2025, 3:02 pm Chris Lee, <clee(dot)hk(at)gmail(dot)com> wrote:
>>>>
>>>>> Hi all,
>>>>>
>>>>> I have 2 postgresql servers. One is the primary and another one is the
>>>>> standby. I am trying to setup repmgr to do the switchover manually.
>>>>> Passwordless ssh have been setup for postgres ID on both servers.
>>>>>
>>>>> I use this command "repmgr standby switchover --log-level=DEBUG
>>>>> --verbose". The standy database is able to promote to be the primary. For
>>>>> the previous primary database, it was shutdown. It was not able to bring up
>>>>> as standby by repmgr.
>>>>>
>>>>> Does anyone encounter this issue before? Thanks a lot for any
>>>>> suggestions.
>>>>>
>>>>> Here is my OS and DB versions:
>>>>>
>>>>> OS version: CentOS Stream release 8
>>>>> Postgres DB version: 15.12
>>>>> rempmgr version: 5.5.0
>>>>>
>>>>> Here is the repmgr conf files:
>>>>> >>>>>
>>>>> node_id=1 # Use 2 on standby
>>>>> node_name='primary'
>>>>> conninfo='host=centos804 user=repmgr dbname=repmgr password=xxx
>>>>> connect_timeout=15'
>>>>> use_primary_conninfo_password=true
>>>>> data_directory='/var/lib/pgsql/15/data' # Adjust for your setup
>>>>> pg_bindir='/usr/pgsql-15/bin'
>>>>> service_start_command = 'sudo systemctl start postgresql-15'
>>>>> service_stop_command = 'sudo systemctl stop postgresql-15'
>>>>> <<<<<
>>>>>
>>>>> >>>>>
>>>>> node_id=2 # Use 2 on standby
>>>>> node_name='standby'
>>>>> conninfo='host=centos803 user=repmgr dbname=repmgr password=xxx
>>>>> connect_timeout=15'
>>>>> use_primary_conninfo_password=true
>>>>> data_directory='/var/lib/pgsql/15/data' # Adjust for your setup
>>>>> pg_bindir='/usr/pgsql-15/bin'
>>>>> service_start_command = 'sudo systemctl start postgresql-15'
>>>>> service_stop_command = 'sudo systemctl stop postgresql-15'
>>>>> <<<<<
>>>>>
>>>>> Regards,
>>>>> Chris
>>>>>
>>>>