Lock value: If enabled, will prevent Moodle users and admins from editing the field directly. Use this option if you are maintaining this data in the external auth system.
You can lock user data fields. This is useful for sites where the user data is maintained by the administrators manually by editing user records or uploading using the \'Upload users\' facility. If you are locking fields that are required by Moodle, make sure that you provide that data when creating user accounts or the accounts will be unusable.
Consider setting the lock mode to \'Unlocked if empty\' to avoid this problem.
Update local: If enabled, the field will be updated (from external auth) every time the user logs in or there is a user synchronisation. Fields set to update locally should be locked.
Update external: If enabled, the external auth will be updated when the user record is updated. Fields should be unlocked to allow edits.
Note: Updating external LDAP data requires that you set binddn and bindpw to a bind-user with editing privileges to all the user records. It currently does not preserve multi-valued attributes, and will remove extra values on update.