Files

T

steffen f2257eae40

Build and Push backhaul-agent / build (push) Successful in 42s

backhaul-agent: public containerized DB-backup client

One docker run on a database's private network starts backing it up:
- backhaul-agent.py: stdlib-only sidecar — every-minute check-in, app-owned
  dump schedule, streams pg_dump/mysqldump/mongodump home chunked, self-updates.
- entrypoint.sh: bootstraps the newest script, installs the once-a-minute cron
  (sources persisted env), runs once immediately, hands off to cron; logs to a
  file surfaced via docker logs.
- Dockerfile: debian-slim + pg_dump 17 (PGDG — required for Postgres 17 servers)
  + mysql client. Mongo tools to follow.
- CI builds + pushes the public image and asserts the dump tools are present.

2026-08-11 13:56:01 +02:00

2.0 KiB

Raw Blame History

backhaul-agent

The public, containerized client for backhaul — a database-backup dashboard with proven restore. Run this as a sidecar on your database's private Docker network: it reaches the database internally and pushes dumps home over HTTPS. No inbound ports are ever opened — the agent only makes outbound calls.

How it works

Once a minute (in-container cron) the agent checks in: it heartbeats, reports the databases it can see, delivers any finished dump, and asks what to do.
The app owns the schedule. When a dump is due, the check-in reply says so; the agent runs pg_dump/mysqldump/mongodump and streams the result home chunked — never buffering the whole dump in memory or on disk.
The agent self-updates: the app advertises the current script version and the agent swaps its own script atomically (after a compile check). Disable with BACKHAUL_AUTOUPDATE=0.

Config pulls, data pushes.

Run it

docker run -d --name backhaul-agent --restart unless-stopped \
  --network <DB_DOCKER_NETWORK> \
  -e BACKHAUL_URL=https://backhaul.skui.io \
  -e BACKHAUL_TOKEN=<token from the backhaul admin> \
  -e BACKHAUL_TARGETS=postgres:<DB_HOST>:5432:<DB_NAME>:<USER>:<PASS> \
  git.skui.io/steffen/backhaul-agent:latest

--network must be the same private Docker network as the database, so the agent can reach it by service name.
BACKHAUL_TARGETS is a comma-separated list, each entry engine:host:port:db:user:pass. Engines: postgres, mysql, mariadb, mongo.

The agent registers each target with the app on its first check-in; tune the dump cadence, retention, and restore-drill schedule from the backhaul dashboard.

What's in the image

Debian slim + Python 3 (stdlib only — the agent has no Python dependencies) + postgresql-client-17 (pg_dump 17, required to dump Postgres 17 servers) + default-mysql-client. MongoDB tools are added in a follow-up.

Logs

docker logs -f backhaul-agent          # check-in activity