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/// @startDocuBlock DatabaseDirectory
/// @brief path to the database
/// `--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
/// ```
/// @endDocuBlock
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