[Help] Backing up mariadb with "mariadb-backup"

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The Basics

  • Nextcloud Server version (e.g., 29.x.x):
    • Nextcloud Hub 25 Autumn (32.0.4)
  • Operating system and version (e.g., Ubuntu 24.04):
    • TrueNAS SCALE Community Edition 25.10.1 - Goldeye
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    • nginx/1.28.0
  • Reverse proxy and version _(e.g. nginx 1.27.2)
    • caddy v2.10.2
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    • PHP 8.4.16
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  • Installation method (e.g. AlO, NCP, Bare Metal/Archive, etc.)
    • docker image linuxserver/nextcloud
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    • No

Summary of the issue you are facing:

I would to do a periodical backup. As the instance is running on ZFS, I take periodical snaphots of all the files and settings and back them up. The issue is the database. The instance is running on MariaDB. I know the official recommendation is mysqldump/mariadb-dump. However, it takes hours to do a full backup.

I am thinking about an alternative that utilizes mariadb-backup to do an incremental backup and running the following script periodically after a full backup:

#!/bin/bash

export BACKUP_DIR_IN_CONTAINER='/config/backup/2026-01-16'

ts=$(date +'%Y-%m-%d_%H-%M-%S%z')
docker exec nextcloud occ maintenance:mode --on
docker exec nextcloud-mariadb mariadb-backup --backup \
	--databases="nextcloud" \
	--target-dir="${BACKUP_DIR_IN_CONTAINER}/incremental-${ts}/" \
	--incremental-basedir="${BACKUP_DIR_IN_CONTAINER}/base/" \
	--user=ncuser \
	--password="mypassword"
docker exec nextcloud occ maintenance:mode --off

Is it a viable solution? Any other thing I have missed?

Many thanks.

2

After running it a couple days, I realized that incremental backups are not any quicker than backing up with mysqldump/mariadb-dump but it is significant susceptible to corruptions.

I understand the reasons behind the official approach now.

Due to the extended down time with mysqldump/mariadb-dump , is a master-slave cluster the best compromise in term of redundancy?

3

For people in the future who may run into this situation:

I discovered there are commands for taking snapshots of the database with external tools. They are called BACKUP STAGE. It is a much quicker solution I have been waiting for.