# ownCloud 9.0 Server Administration Manual

# Migrating to a Different Server

If the need arises ownCloud can be migrated to a different server. A typical use case would be a hardware change or a migration from the virtual Appliance to a physical server. All migrations have to be performed with ownCloud offline and no accesses being made. Online migration is supported by ownCloud only when implementing industry standard clustering and HA solutions before ownCloud is installed for the first time.

To start let us be specific about the use case. A configured ownCloud instance runs reliably on one machine. For some reason (e.g. more powerful machine is available but a move to a clustered environment not yet needed) the instance needs to be moved to a new machine. Depending on the size of the ownCloud instance the migration might take several hours. As a prerequisite it is assumed that the end users reach the ownCloud instance via a virtual hostname (a `CNAME` record in DNS) which can be pointed at the new location. It is also assumed that the authentication method (e.g. LDAP) remains the same after the migration.

Note

At NO TIME any changes to the ORIGINAL system are required EXCEPT putting ownCloud into maintenance mode.

This ensures, should anything unforseen happen you can go back to your existing installation and provide your users with a running ownCloud while debugging the problem.

1. Set up the new machine with the desired OS, install and configure the Web server as well as PHP for ownCloud (e.g. permissions or file upload size limits) and make sure the PHP version matches ownCloud supported configuration and all relevant PHP extensions are installed. Also set up the database and make sure it is an ownCloud supported configuration. If your original machine was installed recently just copying that base configuration is a safe best practice.
2. On the original machine then stop ownCloud. First activate the maintenance mode. After waiting for 6-7 minutes for all sync clients to register the server as in maintenance mode stop the application and/or Web server that serves ownCloud.
3. Create a dump from the database and copy it to the new machine. There import it in the database (See Backing up ownCloud and Restoring ownCloud).
4. Copy all files from your ownCloud instance, the ownCloud program files, the data files, the log files and the configuration files, to the new machine (See Backing up ownCloud and Restoring ownCloud). The data files should keep their original timestamp (can be done by using `rsync` with `-t` option) otherwise the clients will re-download all the files after the migration. Depending on the original installation method and the OS the files are located in different locations. On the new system make sure to pick the appropriate locations. If you change any paths, make sure to adopt the paths in the ownCloud config.php file. Note: This step might take several hours, depending on your installation.
5. While still having ownCloud in maintenance mode (confirm!) and BEFORE changing the `CNAME` record in the DNS start up the database, Web server / application server on the new machine and point your web browser to the migrated ownCloud instance. Confirm that you see the maintenance mode notice, that a logfile entry is written by both the Web server and ownCloud and that no error messages occur. Then take ownCloud out of maintenance mode and repeat. Log in as admin and confirm normal function of ownCloud.
6. Change the `CNAME` entry in the DNS to point your users to the new location.