ArangoDB Server Database Options

Auto upgrade

--database.auto-upgrade

Specifying this option will make the server perform a database upgrade instead of starting the server normally. A database upgrade will first compare the version number stored in the file VERSION in the database directory with the current server version.

If the version number found in the database directory is higher than the version number the server is running, the server expects this is an unintentional downgrade and will warn about this. Using the server in these conditions is neither recommended nor supported.

If the version number found in the database directory is lower than the version number the server is running, the server will check whether there are any upgrade tasks to perform. It will then execute all required upgrade tasks and print their statuses. If one of the upgrade tasks fails, the server will exit with an error. Re-starting the server with the upgrade option will then again trigger the upgrade check and execution until the problem is fixed.

Whether or not this option is specified, the server will always perform a version check on startup. Running the server with a non-matching version number in the VERSION file will make the server refuse to start.

Directory

--database.directory directory

The directory containing the collections and datafiles. Defaults to /var/lib/arango. When specifying the database directory, please make sure the directory is actually writable by the arangod process.

You should further not use a database directory which is provided by a network filesystem such as NFS. The reason is that networked filesystems might cause inconsistencies when there are multiple parallel readers or writers or they lack features required by arangod (e.g. flock()).

directory

When using the command line version, you can simply supply the database directory as argument.

Examples

> ./arangod --server.endpoint tcp://127.0.0.1:8529 --database.directory
/tmp/vocbase

Database directory state precondition

--database.required-directory-state state

Using this option it is possible to require the database directory to be in a specific state on startup. the options for this value are:

• non-existing: database directory must not exist
• existing: database directory must exist
• empty: database directory must exist but be empty
• populated: database directory must exist and contain specific files already
• any: any directory state allowed

Force syncing of properties

--database.force-sync-properties boolean

Force syncing of collection properties to disk

Force syncing of collection properties to disk after creating a collection or updating its properties.

If turned off, no fsync will happen for the collection and database properties stored in parameter.json files in the file system. Turning off this option will speed up workloads that create and drop a lot of collections (e.g. test suites).

The default is true.

Wait for sync

--database.wait-for-sync boolean

Default wait for sync behavior

Default wait-for-sync value. Can be overwritten when creating a new collection.

The default is false.

More advanced options

--database.replication-applier flag

Enable/disable replication applier.

If false the server will start with replication appliers turned off, even if the replication appliers are configured with the autoStart option. Using the command-line option will not change the value of the autoStart option in the applier configuration, but will suppress auto-starting the replication applier just once.

If the option is not used, ArangoDB will read the applier configuration from the file REPLICATION-APPLIER-CONFIG on startup, and use the value of the autoStart attribute from this file.

The default is true.