# Sessions

LL::NG rely on a session mechanism with the session ID as a shared secret between the user (in SSO cookie) and the session database.

To configure sessions, go in Manager, `General Parameters` » `Sessions`:

- Store user password in session data: see password store documentation.
- Sessions timeout: Maximum lifetime of a session. Old sessions are deleted by a cron script.
- Sessions activity timeout: Maximum inactivity duration.
- Sessions update interval: Minimum interval used to update session when activity timeout is set.

Session activity timeout requires Handlers to have a write access to sessions database.

- Opening conditions: rules which are evaluated before granting session, see Grant Session plugin documentation
- Sessions Storage: you can define here which session backend to use, with the backend options. See sessions database configuration to know which modules you can use. Here are some global options that you can use with all sessions backends:
  - generateModule: allows one to override the default module that generates sessions identifiers. For security reasons, we recommend to use Lemonldap::NG::Common::Apache::Session::Generate::SHA256
  - IDLength: length of sessions identifiers. Max is 32 for MD5 and 64 for SHA256
- Multiple sessions, you can restrict the number of open sessions:
  - One session per user: when a user logs in, all their previous sessions are removed
  - One IP address per user: when a user logs in, all their previous sessions on a different IP address are removed
  - One user per IP address: when a user logs in, all sessions that belong to a different user on that IP address are removed
  - Display deleted sessions: display deleted sessions on authentication phase.
  - Display other sessions : display other sessions on authentication phase, with a link to delete them.
- Persistent sessions: are used for storing users log in history, 2F devices, OIDCConsents and so on. Heavy organizations may have to disable persistent sessions storage to avoid too many database tuples.
  - Disable storage: Do not store user persitent sessions.

Note that since HTTP protocol is not connected, restrictions are not applied to the new session: the oldest are destroyed.

# Command-line tools

- LLNG Portal provides a simple tool to delete a session: `llngDeleteSession`. To use it, simply give it the user identifier (wildcard are authorizated):

    # Delete all sessions opened by user "dwho"
    $ llngDeleteSession dwho
    # Delete all sessions opened by user starting with "dh"
    $ llngDeleteSession dh*
    # Delete all sessions:
    $ llngDeleteSession *