Thanks @paul, that’s very helpful to know.
Mattermost offers a User Filter LDAP setting, which allows you to query which users have access to Mattermost. I think this might work for your case.
In particular, you might consider
- setting an attribute in LDAP that defines which users are authorized to use Mattermost
- use the User Filter setting to select those users.
Anyone not selected by the filter wouldn’t be able to log in to Mattermost.
Let me know if that might work, or if you have any questions about it?