The way to backup Orthanc depends on the database back-end that is used. In any case, you of course have to backup your configuration file.
By default, Orthanc uses SQLite to store its database. In this case, all the DICOM files together with the SQLite index are stored directly in the filesystem. The backup procedure works as follows:
OrthancStoragefolder next to the configuration file).
OrthancStorage/index*files next to the configuration file).
It is mandatory to stop Orthanc, as the Orthanc core makes the assumption that it is the only process to access the SQLite database at any time.
Karsten Hilbert provided us with a sample backup script for the official Debian package of Orthanc that automates this backup procedure. Note that in this script, the call to the SQLite command-line tool is used to force the WAL replay. This manual replay should not be necessary for Orthanc >= 0.7.3.
The default SQLite engine is well adapted for DICOM routing or for image buffering tasks, but not for enterprise scenarios. In such cases, you are highly recommended to use the PostgreSQL back-end.
If using PostgreSQL, you can do hot backups (i.e. while Orthanc is running), and you benefit from all the flexibility of PostgreSQL backup. These procedures are out of the scope of this manual. Please check the official backup and restore manual.