matrix-docker-ansible-deploy/docs/maintenance-migrating.md

> **Note**: This migration guide is applicable if you migrate from one server to another server having the same CPU architecture (e.g. both servers being `amd64`).
>
> If you're trying to migrate between different architectures (e.g. `amd64` --> `arm64`), simply copying the complete `/matrix` directory is not possible as it would move the raw PostgreSQL data (`/matrix/postgres/data`) between different architectures. In this specific case, you can use the guide below as a reference, but you would also need to avoid syncing `/matrix/postgres/data` to the new host, and also dump the database on your current server and import it properly on the new server. See our [Backing up PostgreSQL](maintenance-postgres.md#backing-up-postgresql) docs for help with PostgreSQL backup/restore.

# Migrating to new server

This documentation explains how to migrate your Matrix services (server, client, bridges, etc.) from an old server to a new server.

## Lower DNS TTL

Prepare by lowering DNS TTL for your domains (`matrix.example.com`, etc.), so that DNS record changes would happen faster, leading to less downtime.

## Stop services on the old server

Before migrating, you need to stop all services on the old server and make sure they won't be starting again.

To stop the services, go to the `matrix-docker-ansible-deploy` directory on your local computer, and run the command:

```sh
ansible-playbook -i inventory/hosts setup.yml --tags=stop
```

Alternatively, you can log in to the old server and run the command (you might have to `cd` to `/etc/systemd/system/` first):

```sh
systemctl disable --now matrix*
```

## Copy data directory from the old to the new server

Then, copy directory `/matrix` from the old server to the new server. When copying, make sure to preserve ownership and permissions (use `cp -p` or `rsync -ar`)!

## Adjust DNS records

Make sure your DNS records are adjusted to point to the new server's IP address.

## Update `hosts` file

Having adjusted DNS records, remove old server from the `inventory/hosts` file, and add new server to it.

## Create `matrix` user and group on the new server

After updating `inventory/hosts` file, run the command below to create the `matrix` user and group on the new server:

```sh
ansible-playbook -i inventory/hosts setup.yml --tags=setup-system-user
```

**Note**: because the `matrix` user and group are created dynamically on each server, the user/group ID may differ between the old and new server. We suggest that you adjust ownership of `/matrix` files. To adjust the ownership, log in to the new server and run the command:

```sh
chown -R matrix:matrix /matrix
```

## Start all services on the new server

Finally, run the command below to finish the installation and start all services:

```sh
ansible-playbook -i inventory/hosts setup.yml --tags=setup-all,start
```