Leaving Noust

Noust does not sit between your applications and the machine. An application it deployed is a systemd unit, an nginx or Apache site, a directory and a .env file: ordinary things that go on working when Noust is stopped, removed, or never installed again. This page says what those things are, how to stop depending on Noust without stopping anything, and how to take Noust off the server afterwards. Nothing here needs Noust to be running except the first step.

The test of this page is the one every other page of Noust keeps: after you follow it, systemctl, journalctl, your web server and git are enough to run the server.

Before you go

Keep a copy of what Noust knows that the server does not show:

noust list                                   # every application, so none is forgotten
noust app export shop.example.com -o shop.json            # its settings, domains, health check, cron, variables, mounts
noust app export shop.example.com --as-yaml -o noust.yaml  # the same as a file for the repository
noust backup create shop.example.com --include-databases   # the files, with the databases it uses
noust env show shop.example.com --unmask     # the variables in clear, once, to a place you trust

app export keeps secrets out unless you ask for --with-secrets. The .env is a plain file (see below), so a copy of it is a copy of the variables. The audit log, the deployment history and the metrics are in the store (/var/lib/noust/noust.db) and stay there; export them if you need them.

What an application is, without Noust

Databases are the servers' own (PostgreSQL, MySQL, MariaDB, Redis, MongoDB) and keep their own data directories and roles; the credentials Noust created are roles of those servers, and the DATABASE_URL in an application's .env is the only trace of them. An engine Noust runs in a container (noust-db-*) is a Compose project under /var/lib/noust/ with its own data directory.

Taking Noust out of the way

Noust's own units are what to stop. None of the application units depends on them.

systemctl disable --now noust-web noust-monitor noust-previews.timer
systemctl list-unit-files 'noust-*' --no-legend      # everything else Noust wrote

Read that list before you remove anything:

Then, what changes in how you work:

• Deploying is yours again: git pull in repo/, build, ln -sfn the new release into current, systemctl restart <app>. The unit does not care who made the release.
• Environment changes are edits of the .env file and a restart. A reference such as {{project.NAME}} or {{secret:vault/path}} in the console is already resolved in the file; the text it came from lives only in the store.
• Certificates renew by certbot's timer. A name Noust issued through a DNS provider needs that provider's credentials in certbot's own configuration; check certbot certificates.
• Backups of the files are tar of the application directory and a dump of its databases.
• Sandboxed builds ran as noust-build in a transient unit; a build you run yourself is yours.

Coming back

A site you stop managing, or one Noust never deployed, can be registered again without rebuilding it: noust app adopt-site (Adopting sites that already run). Deleting an adopted site only forgets it.

Making the files yours

Every unit and site Noust writes starts with # Generated by Noust. That line is the only thing that decides whether Noust may rewrite or delete the file. If you keep using Noust on the server for some applications and want others left alone for good, delete the first line of their unit and site and Noust treats them as yours: it never rewrites a site or unit without the marker (an update says so and leaves the file). Removing the line from every file is also how you make a later re-install of Noust leave the server's applications alone.

grep -l 'Generated by Noust' /etc/systemd/system/*.service /etc/nginx/sites-available/* 2>/dev/null

Removing Noust

When nothing you kept needs the command any more:

apt remove noust        # or: dnf remove noust, zypper remove noust, pip uninstall noust

The package stops and disables the console and the monitor (noust-web, noust-monitor) and touches nothing else: your applications, their units and sites, the configuration, the store and the backups stay. apt purge goes one step further and removes /etc/noust, /var/log/noust and the two unit files, and still leaves /var/www/apps and /var/lib/noust. Everything below stays until you remove it yourself:

A server that came through 3.x may still carry links under the product's old names beside these paths; noust setup retire-links removes the ones nothing uses, and rm removes any that is left.

What a stopped Noust does

Nothing. Noust is not a daemon your applications call: it has no resident program in them and no proxy in front of them. The requests it makes on its own are the update check (GitHub and the package repository; updates.check: false turns it off) and the ones you configured (notifications, backup destinations, a Git host); there is no telemetry or error reporting to anyone else. Its data is in files you can read: the store is SQLite, the backups are tarballs with a manifest, the .env files are the applications' own.