configuration.md

Configuration

To configure JULEA, the julea-config tool can be used. Configuration files are typically saved in ~/.config/julea (if --user is specified) or /etc/xdg/julea (if --system is specified). For an example invocation of julea-config, please refer to the Quick Start.

JULEA supports multiple configurations that can be selected at runtime using the JULEA_CONFIG environment variable. They can be created using the --name parameter when calling julea-config. If no name is specified, the default (julea) is used.

Backends

JULEA supports multiple backends that can be used for object, key-value or database storage. It is possible to use them either on the client or on the server. The following tables visualize all supported types and special configuration parameters. Some backends might require third-party servers to be usable. Please also refer to the documentation about containers.

The backend paths can contain the special string {PORT}, which will be replaced with the server's port at runtime. This can be used to run two servers on the same machine, as sharing backend paths among multiple instances will typically lead to problems.

Object Backends

Backend	Client	Server	Path format
gio	❌	✔	Path to a directory (/var/storage/gio)
null	❌	✔
posix	❌	✔	Path to a directory (/var/storage/posix)
rados	✔	❌	Path to a configuration file and pool name (/etc/ceph/ceph.conf:data)

Key-Value Backends

Backend	Client	Server	Path format
gdbm	❌	✔	Path to a file (/var/storage/gdbm)
leveldb	❌	✔	Path to a directory (/var/storage/leveldb)
lmdb	❌	✔	Path to a directory (/var/storage/lmdb)
mongodb	✔	❌	Host and database (127.0.0.1:julea_db)
null	❌	✔
rocksdb	❌	✔	Path to a directory (/var/storage/rocksdb)
sqlite	❌	✔	Path to a file (/var/storage/sqlite.db)

Database Backends

Backend	Client	Server	Path format
mysql	✔	❌	Host, database, user and password (127.0.0.1:julea_db:julea_user:julea_pw)
null	❌	✔
sqlite	❌	✔	Path to a file (/var/storage/sqlite.db) or :memory: for an in-memory database