It's a good practice to backup your database and your preview files. Here is a quick guide to backup all the required files. You will find information too about how to restore them.

Backup database

To run a backup of the Zou database, run the following command:

cd /opt/zou/backups
DB_PASSWORD=mysecretpassword /opt/zou/zouenv/bin/zou dump-database

All data will be stored in a file in the current directory. The generated file name will follow this format: 2021-03-21-zou-db-backup.sql.gz


To restore the database to a new Postgres instance make sure the source and target version of the api match, otherwise the database schema may not match, if all matches run

gunzip 2021-03-21-zou-db-backup.sql.gz
createdb -h localhost -p 5432 -U postgres targetdb
psql -h yourphost -p 5432 -U postgres -1 -d targetdb -f 2021-03-21-zou-db-backup.sql

you can also just write directly to zoudb (the default database):

gunzip 2021-03-21-zou-db-backup.sql.gz
psql -h yourphost -p 5432 -U postgres -1 -d zoudb -f 2021-03-21-zou-db-backup.sql

when writing to a previously created database, make sure to terminate all the connections to said database by using the following statement:

SELECT pg_terminate_backend (pid) FROM pg_stat_activity WHERE datname = 'zoudb';

you can also change the name of a database to convert it to the default db:


you can also change the database being used by using an environment variable in



Backup files

If you rely on an object storage, you have to check with your provider that your data are properly replicated.

If you store your files directly on your drive, you must backup the preview folder (/opt/zou/previews by default). There are plenty of documentation and tools available on the internet to do that. We won't cover this subject here.


To restore the files you simply have to put the files from your backups the directory you want. Then make sure thate the PREVIEW_FOLDER environment variable targets it properly.