Technical Tip: Limiting concurrent user authentication

Description

This article describes how to limit concurrent user authentication.  

Scope

FortiOS v7.x to v8.x.

Solution

The same user can be used for multiple concurrent authentications. Its maximum number can be limited globally or per user-group only via CLI.

Globally:

config system global
    set policy-auth-concurrent 10
end

Per user-group:

config user group
    edit <group-name>
        set auth-concurrent-override enable
        set auth-concurrent-value <number_of_max_concurrent_users>
    next
end

Note:

SAML user groups are not affected by the auth-concurrent settings, and the concurrent sessions of SAML users should be managed with the IdP.