https://github.com/spantaleev/matrix-docker-ansible-deploy/blob/450e96526c9d31605ff57c63a74cfa6599d03ad3/docs/maintenance-migrating.md?plain=1
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 between different architectures. In this specific case, you can use the guide below as a reference, but you would also need to dump the database on your current server and import it properly on the new server. See our Backing up PostgreSQL docs for help with PostgreSQL backup/restore.
Migrating to new server
Prepare by lowering DNS TTL for your domains (matrix.DOMAIN, etc.), so that DNS record changes (step 4 below) would happen faster, leading to less downtime
Stop all services on the old server and make sure they won’t be starting again. Execute this on the old server: systemctl disable --now matrix* (you might have to cd to /etc/systemd/system/ first)
Copy directory /matrix from the old server to the new server. Make sure to preserve ownership and permissions (use cp -p or rsync -ar)!
Make sure your DNS records are adjusted to point to the new server’s IP address
Remove old server from the inventory/hosts file and add new server.
Run ansible-playbook -i inventory/hosts setup.yml --tags=setup-system-user. This will create the matrix user and group on the new server
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 manually by running this on the new server: chown -R matrix:matrix /matrix.
Run ansible-playbook -i inventory/hosts setup.yml --tags=setup-all,start to finish the installation and start all services