Re: failed to setup barman backup when Posgres is running in Podman Container

Am 16.01.24 um 09:54 schrieb Romas Kontrimas:
> Hi,
>
> If I understand correctly, you already have WAL streaming setup and
> it's in OK state (setting in in conf streaming_archiver = on). Barman
> will continuously receive and archive transaction logs. Why would you
> still need standard archive_command?
> https://docs.pgbarman.org/release/3.9.0/#wal-streaming
>
>
>
> On Thu, 11 Jan 2024 at 11:13, duc hiep ha <haduchiep(at)googlemail(dot)com>
> wrote:
>
>
> Dear All,
>
>
> I am trying to use Barman to back up PostgreSQL, which is running
> in a Podman container. However, I encounter the error "WAL
> archive: FAILED," as shown below:
>
> #barman check testdb
> Server testdb:
> WAL archive: FAILED (please make sure WAL shipping is set up)
> PostgreSQL: OK
> superuser: OK
> PostgreSQL streaming: OK
> wal_level: OK
> replication slot: OK
> directories: OK
> retention policy settings: OK
> backup maximum age: OK (no last_backup_maximum_age provided)
> compression settings: OK
> failed backups: OK (there are 0 failed backups)
> minimum redundancy requirements: OK (have 0 backups, expected
> at least 0)
> pg_basebackup: OK
> pg_basebackup compatible: OK
> pg_basebackup supports tablespaces mapping: OK
> pg_receivexlog: OK
> pg_receivexlog compatible: OK
> receive-wal running: OK
> archiver errors: OK
>
> I have identified that normally, when the PostgreSQL database is
> installed on a regular VM (not in a container), the
> archive_command parameter under postgresql.conf looks like this:
>
> archive_command = 'rsync -a %p
> barman(at)barman-backup-server-ip:/data/barman/main-db-server/incoming/%f'
>
> However, when PostgreSQL is installed on a Podman container, I
> cannot use the above archive_command because within the PostgreSQL
> container, it doesn't understand rsync, ssh, and the barman user.
> That's why I have to use a normal copy command like:
>
>           archive_command = 'cp -i %p /srv/archive/%f'
>
> I then mounted this wal-files folder on
> '/data/barman/main-db-server/incoming/%f'. As a result, all these
> wal_files have the PostgreSQL ownership and not the barman
> ownership. The barman user has no privileges to change these
> wal-files, which is why the WAL archive is marked as FAILED.
>
> Do you know how to solve this issue? do I have to install Barman
> and PostgreSQL in the same Pod container in order to backup 
> PostgreSQL container? Or is there another solution to this problem?
>
> Thank you for your support in advance.
>
> Best,
> Ha
>

> Why would you still need standard archive_command?

You need it only if the streaming secondary servers are offline for a
while and cannot stream old WAL files from the primary because the have
been deleted there.

Archive shipping can then come to the rescue, so that the standby server
can get the missing WAL file from the archive. Subsequently, it will
continue to stream directly from the primary.

Regards,

Holger

--
Holger Jakobs, Bergisch Gladbach, Tel. +49-178-9759012