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@@ -30,6 +30,22 @@ We at OPL use `docker-compose` both for provisioning our development machines as
 
 ### Backup & restore
 
+There are two databases that are vital for the systems integrity. They contain the "source of truth" for the state in the system: *MySQL* holds all the patrons, items and ciruclation data, and *Fuseki* is master for the knowledge graph representing the catalog and related metadata. Needless to say, backups of those should be performed regularly and stored in a safe place.
+
+All databases in the system use docker volumes to persist data.
+
+#### MySQL
+
+Normally, we take backups by simply copying the datavolume, but in the case of MySQL, we found there is a risk of getting a corrupted backup, probably due to the large number of writes happening at any time. So to get a safe snapshot of the data use mysqldump:
+
+    docker exec -i koha_mysql_slave bash -c 'mysqldump -uroot -p$MYSQL_PASSWORD $MYSQL_DATABASE --single-transaction --master-data=2 --flush-logs --routines --triggers --events --hex-blob' > /data/dumps/`date +%F`/koha_mysqldump_full.sql
+
+At OPL we are running the backup against a read-only slave, as not to create additional burden on the master DB.
+
+#### Fuseki
+
+#### Others
+
 ## Customizations
 
 ### Internationalization