Date: Mon, 8 Feb 2021 12:23:21 +0700
From: Victor Sudakov <vas@sibptus.ru>
To: pgsql-admin@lists.postgresql.org
Subject: Re: wal-g (https://github.com/wal-g/wal-g) reliability
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Nikolay Samokhvalov wrote:
> In short, it's reliable and battle-tested. It's used in  companies such as
> Yandex.Cloud and GitLab.com, successfully.

Nikolay, don't you mind another question? 

I'm used to the fact that "pg_basebackup -X" creates a self-sufficient
backup of a cluster which can be started right away as it contains all
the WAL files required for recovery. `touch recovery.signal` is never necessary,
and `touch standby.signal` is optional (when you do PITR etc).

It's not the case with wal-g, the result of the `wal-g backup-fetch` 
command requires `touch recovery.signal` and a restore_command
configured to fetch WALs from the wal-g storage.

I have also noticed that wal-g keeps pg_control in a separate tar
archive, and keeps a lot of metadata.

The questions are: 

1. If the metadata in the wal-g storage ever becomes corrupt, will I be
able to restore the database manually from the archives in
$WALG_*_PREFIX/{basebackups,wal}_005/ ?

2. Is there a `wal-g backup-fetch` option for truly self-sufficient
restoration?

-- 
Victor Sudakov,  VAS4-RIPE, VAS47-RIPN
2:5005/49@fidonet http://vas.tomsk.ru/