v3.2.2 · Prometheus-native backup monitoring

Know your backups ran.
Before you need them.

backmon watches backup files in filesystems and S3-compatible object storage and turns them into Prometheus metrics you can graph and alert on.

Get started Star on GitHub

$ helm install dreitier/backmon

Backup statusillustrative data

DiskGroupFilesLatest sizeStatus

mysql-dumpsdaily7 / 71.84 GBOK

postgres-walhourly24 / 24312 MBOK

photos-archiveweekly3 / 448.2 GBLATE

s3-photosweekly0 / 40 BMISSING

Works withPrometheusGrafanaAlertmanagerAWS S3MinIODockerHelmRancher

Features

Everything you need to trust your backups

Filesystems & object storage

Watch backup files on local disks or in S3-compatible storage like AWS S3 and MinIO.

s3://backups

mysql/2026-10-13.sql.gz     1.8 GB
mysql/2026-10-12.sql.gz     1.8 GB
photos/2026-w41.tar        48.2 GB

Alert on failures

Get notified when a backup is missing, too small or too old.

BackupMissings3-photos · weekly

Multiple environments

One instance, many storages, each with its own rules.

aws-prodminio-devnas-local

Prometheus metrics

Presence, size, age and duration of every backup, ready for Prometheus and Grafana.

Purge old backups

Remove outdated backup files automatically so storage does not fill up.

Central download

Download backup files from one place instead of logging into every storage.

How it works

From a config file to an alert in three steps

StoragebackmonPrometheusAlertmanager

1. Describe
2. Scan
3. Alert

Tell backmon which disks to watch and what a healthy backup group looks like.

config.yaml

environments:
  aws-test-environment:
    disks:
      include:
        - s3-photos
    region: eu-central-1

On every interval it inspects your storages and exposes the result for Prometheus.

GET /metrics

backmon_backup_file_count{disk="mysql-dumps"} 7
backmon_backup_file_count_max{disk="mysql-dumps"} 7
backmon_backup_file_count{disk="s3-photos"} 0
backmon_backup_file_count_max{disk="s3-photos"} 4

A Prometheus rule on those metrics notifies your team before you ever need the backup.

alert rule

- alert: BackupMissing
  expr: backmon_backup_file_count
    < backmon_backup_file_count_max
  for: 15m
FIRING  disk="s3-photos"

Install

Up and running in a minute

Docker

shell

docker run -p 8000:8000 \
  -v "$PWD/config.yaml:/etc/backmon/config.yaml" \
  dreitier/backmon

Helm