--- title: Migrating to a new machine description: Copying your Mastodon installation to a new server without losing anything. menu: docs: weight: 90 parent: admin --- Sometimes, for various reasons, you may want to migrate your Mastodon instance from one server to another. Fortunately, this is not too difficult of a process, although it may result in some downtime. {{< hint style="info" >}} This guide was written with Ubuntu Server in mind; your mileage may vary for other setups. {{< /hint >}} ## Basic steps {#basic-steps} 1. Set up a new Mastodon server using the [Production Guide]({{< relref "install" >}}) (however, don’t run `mastodon:setup` and only leave the PostgreSQL service running). 2. Stop Mastodon on the old server (e.g. `systemctl stop 'mastodon-*.service'`). 3. Dump and load the PostgreSQL database using the instructions below. 4. Copy the `system/` files using the instructions below. (Note: if you’re using S3, you can skip this step.) 5. Copy the `.env.production` file. 6. Save the Redis database, stop the Redis service, and copy the Redis database from `/var/lib/redis/` to the new server. 7. Run `RAILS_ENV=production bundle exec rails assets:precompile` to compile Mastodon 8. Start Mastodon and Redis on the new server. 9. Run `RAILS_ENV=production ./bin/tootctl feeds build` to rebuild the home timelines for each user. 10. Run `RAILS_ENV=production ./bin/tootctl search deploy` to rebuild your Elasticsearch indices (Note: if you are not using Elasticsearch, you can skip this step.) 11. Update your DNS settings to point to the new server. 12. Update or copy your Nginx configuration, and re-run LetsEncrypt as necessary. 13. Enjoy your new server! ## Detailed steps {#detailed-steps} ### Stop the Mastodon services ```bash systemctl stop 'mastodon-*.service' ``` ### What data needs to be migrated {#what-data-needs-to-be-migrated} At a high level, you’ll need to copy over the following: * The `~/live/public/system` directory, which contains user-uploaded images and videos (if using S3, you don’t need this) * The PostgreSQL database (using [pg_dump](https://www.postgresql.org/docs/9.1/static/backup-dump.html)) * The `~/live/.env.production` file, which contains server config and secrets * The Redis database in the `/var/lib/redis/` directory, which contains unproccessed Sidekiq jobs. Less crucially, you’ll probably also want to copy the following for convenience: * The nginx config (under `/etc/nginx/sites-available/mastodon`) * The SSL certificates for your domain (under `/etc/letsencrypt/live/` if using LetsEncrypt) * The systemd config files (`/etc/systemd/system/mastodon-*.service`), which may contain your server tweaks and customizations * The PgBouncer configuration under `/etc/pgbouncer` (if you’re using it) ### Dump and load PostgreSQL {#dump-and-load-postgresql} Instead of running `mastodon:setup`, we’re going to create an empty PostgreSQL database using the `template0` database (which is useful when restoring a PostgreSQL dump, [as described in the pg_dump documentation](https://www.postgresql.org/docs/9.1/static/backup-dump.html#BACKUP-DUMP-RESTORE)). If you are using a password for your PostgreSQL user, you may want to configure the `mastodon` user on your new system to use the same password as your old system for convenience: ```bash sudo -u postgres psql ALTER USER mastodon WITH PASSWORD 'YOUR_PASSWORD'; \q ``` Run this as the `mastodon` user on your old system: ```bash pg_dump -Fc mastodon_production -f backup.dump ``` Copy the `backup.dump` file over, using `rsync` or `scp`. Then on the new system, create an empty database as the `mastodon` user: ```bash createdb -T template0 mastodon_production ``` Then import it (replace # in -j# with the number of CPUs in your system to improve restore performance): ```bash pg_restore -Fc -j# -U mastodon -n public --no-owner --role=mastodon \ -d mastodon_production backup.dump ``` (Note that if the username is not `mastodon` on the new server, you should change the `-U` AND `--role` values above. It’s okay if the username is different between the two servers.) ### Copy files {#copy-files} This will probably take some time, and you’ll want to avoid re-copying unnecessarily, so using `rsync` is recommended. On your old machine, as the `mastodon` user, run: ```bash rsync -avz ~/live/public/system/ mastodon@example.com:~/live/public/system/ ``` You’ll want to re-run this if any of the files on the old server change. You should also copy over the `.env.production` file, which contains secrets. Now copy your Redis database over (adjust the location of your Redis database as needed). On your old machine, as the `root` user, run: ```bash redis-cli SAVE EXIT systemctl stop redis-server.service rsync -avz /var/lib/redis/ root@example.com:/var/lib/redis ``` Optionally, you may copy over the nginx, systemd, and PgBouncer config files, or rewrite them from scratch. ### During migration {#during-migration} You can edit the `~/live/public/500.html` page on the old machine if you want to show a nice error message to let existing users know that a migration is in progress. You’ll probably also want to set the DNS TTL to something small (30-60 minutes) about a day in advance, so that DNS can propagate quickly once you point it to the new IP address. ### After migrating {#after-migrating} Run the following commands as your mastodon user: ```bash RAILS_ENV=production bundle exec rails assets:precompile ``` Now run the following commands as your root user: ```bash systemctl daemon-reload systemctl start redis-server systemctl enable --now mastodon-web mastodon-sidekiq mastodon-streaming systemctl restart nginx ``` Once your server is back online, you can rebuild the home feeds for users (this can take a long time depending on the number of users.) ```bash RAILS_ENV=production ./bin/tootctl feeds build ``` If you use Elasticsearch, run the following command to rebuild the indices (this can take a long time depending on the number of statuses you have.) ```bash RAILS_ENV=production ./bin/tootctl search deploy ``` You can check [whatsmydns.net](https://whatsmydns.net/) to see the progress of DNS propagation. To jumpstart the process, you can always edit your own `/etc/hosts` file to point to your new server so you can start playing around with it early.