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docs/maintenance-upgrading-services.md

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+# Upgrading the Matrix services
+
+This playbook not only installs the various Matrix services for you, but can also upgrade them as new versions are made available.
+
+If you want to be notified when new versions of Synapse are released, you should join the Synapse Homeowners room: [#homeowners:matrix.org](https://matrix.to/#/#homeowners:matrix.org).
+
+To upgrade services:
+
+- update your playbook directory (`git pull`), so you'd obtain everything new we've done
+
+- take a look at [the changelog](../CHANGELOG.md) to see if there have been any backward-incompatible changes that you need to take care of
+
+- re-run the [playbook setup](installing.md): `ansible-playbook -i inventory/hosts setup.yml --tags=setup-all`
+
+- restart the services: `ansible-playbook -i inventory/hosts setup.yml --tags=start`
+
+**Note**: major version upgrades to the internal PostgreSQL database are not done automatically. To upgrade it, refer to the [upgrading PostgreSQL guide](maintenance-postgres.md#upgrading-postgresql).