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jarl/docs/operations.md
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abrown38andClaude Opus 5.5 bd6b8778e4 Jarl 0.1.0: manage BIND through a web UI, REST API and CLI
Jarl keeps a BIND 9.20 server's whole configuration (views, ACLs, TSIG
keys, zones of every type, records, named.conf options) in SQLite and
renders named.conf, keys.conf and zone files from it.

Every change goes through one changeset pipeline: whole-configuration
validation, named-checkconf -z and named-checkzone in a staging
directory, atomic install, rndc reconfig/reload, serial verification
with rndc zonestatus, and rollback if named does not load the change.
Changes apply one at a time by default or are bundled and applied
together. Applied changesets can be reverted.

- jarld: the daemon with the REST API and an embedded web UI, plus import,
  adopt, check, resync, backup and local user recovery commands
- jarl: the CLI, including ACME DNS-01 hooks for certbot and acme.sh
- users with argon2id passwords and CSRF-protected sessions; hashed API
  tokens with granular grants and roles; an audit log
- systemd unit, sysusers.d/tmpfiles.d files, Makefile
- unit tests, integration tests against a real named, scripts/e2e.sh
- docs/ guides, README and CHANGELOG

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-07 15:03:13 +00:00

5.0 KiB

Running Jarl

Day to day

Task How
Is everything healthy? jarl status, or the web UI dashboard: named reachable, adoption, drift, open changesets, configuration problems
What changed and who did it? jarl history, jarl changeset show ID (with diff), jarl audit
Undo a change jarl changeset revert ID, review it, then jarl changeset apply NEW_ID (or History → Revert in the UI)
Check the configuration jarl check: full validation plus named-checkconf -z
Logs journalctl -u jarl (jarld, including msg=audit lines), journalctl -u named
Restart / reload TLS systemctl restart jarl / systemctl reload jarl

Restarting jarld doesn't affect DNS: named keeps serving the files it loaded. jarld is only needed to make changes.

Backups

Everything Jarl knows is in its database. The BIND files can be generated from it again at any time.

sudo -u jarl jarld backup /var/backups/jarl/jarl-$(date +%F).db   # consistent copy, safe while jarld runs

For example, as a daily timer or cron job:

# /etc/cron.daily/jarl-backup
#!/bin/sh
set -e
install -d -o jarl -g jarl -m 0700 /var/backups/jarl
sudo -u jarl jarld backup /var/backups/jarl/jarl-$(date +%F).db
find /var/backups/jarl -name 'jarl-*.db' -mtime +30 -delete

The database contains password and token hashes and the TSIG secrets in the clear, so keep backups private.

Restoring

systemctl stop jarl
install -o jarl -g jarl -m 0600 /var/backups/jarl/jarl-2026-10-01.db /var/lib/jarl/jarl.db
rm -f /var/lib/jarl/jarl.db-wal /var/lib/jarl/jarl.db-shm
systemctl start jarl
jarl resync --dry-run     # what differs between the restored database and the files
jarl resync --force       # write everything and reload named

An older backup can carry lower zone serials than named last served. Your own named doesn't mind, but secondaries and caches ignore a serial that went backwards. If you have secondaries, raise the serials after a restore: jarl zone update ZONE --serial <higher>.

Drift: files changed outside Jarl

Jarl keeps a checksum of every file it writes. If someone edits /etc/bind/jarl/named.conf or a zone file by hand (or a restore puts old files back), jarl status and the dashboard show drift, and changes that would overwrite those files are refused with 409 drift:

error: files managed by Jarl were changed outside Jarl: /var/lib/bind/jarl/internal/adbraun.lol.zone; review them and apply with force to overwrite

Decide which version is right:

  • Jarl's (the usual case): jarl resync --force rewrites every file from the database and reloads named. Any single change with --force also overwrites the drifted files.
  • The hand edit: put the same change into Jarl (for example jarl zone import ZONE /var/lib/bind/jarl/internal/adbraun.lol.zone for records), then jarl resync --force.

When an apply fails

Jarl checks everything it can before it touches named, so failures are rare. When one happens, nothing is left half-done:

Stage What you see State afterwards
validation 422 with problems Nothing written
named-checkconf / named-checkzone 422 validation_failed with the checker's messages in check, mapped to the zone/option that caused them Nothing written
rndc reconfig / reload fails, or a zone doesn't load within reload_timeout 502 bind_failed Previous files restored and named reloaded

A failed change is never recorded as applied. A staged changeset stays open, so you can fix it and apply again, and the failure is in the audit log (jarl audit --outcome failure). named's own log usually explains a load failure: journalctl -u named.

If named isn't running, changes fail at the reload step and are rolled back. Start named, then apply again.

Recovering access

Problem Fix (on the server)
Forgot the admin password sudo -u jarl jarld user passwd admin
Locked out by the login rate limit wait 15 minutes, or systemctl restart jarl (the limiter is in memory)
Lost every admin account sudo -u jarl jarld user add --admin rescue
Need a token without the web UI sudo -u jarl jarld user token admin cli

Taking Jarl out of the picture

The generated files are plain BIND configuration. To stop using Jarl, disable the service. named keeps working with /etc/bind/jarl/ exactly as it is. To go back to the configuration you had before adopting:

cp /etc/bind/named.conf.pre-jarl-<date> /etc/bind/named.conf
rndc reconfig

Monitoring

  • GET /healthz (no authentication) reports that jarld is up.
  • GET /api/v1/status with a read-only token reports named reachability, drift and configuration problems. It is suitable for a monitoring check:
    jarl --token @/etc/jarl/monitor.token status -o json | jq -e '.engine.drift == [] and .engine.adopted'
    
  • The audit log records failed logins as auth.login_failed / auth.login_blocked, and rejected tokens as auth.token_failed.