Fortigate Radius logins for SSL VPN with Password expiration/renewal ability
July 27, 2017
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I’ve blogged on using the SSL VPN to renew passwords if they expire before using LDAPS, but I have not blogged on doing this through Radius authentication.
One awesome aspect of this is that by default, the max LDAP servers you can configure on a Fortigate is 10 – so if you have a lot of different domains – as I do with one client – you might be pushed to go to Fortiauthenticator for the ability to have more, or use dual factor. Using Radius to authenticate can help remedy this issue because you can authenticate as many domains as you like behind 1 radius server. You can also have that server allow users to change their password if it expires, or if you set the policy in AD to make the user change their password.
To authenticate many different groups through radius for the SSL VPN you have to configure a vendor specific option. I wrote an entry not long ago on how to do this found here – https://travelingpacket.com/2016/01/26/fortigate-radius-group-authentication/ That was written for 5.2 but same stuff applies to 5.4 and 5.6 .
Once NPS is setup, the Radius server is created on the FGT, User groups are created on the FGT and of course SSL VPN policies are good to – you can modify the server in CLI and set the options to allow passwords to be change if expired.
In this case my server is called Presrv04 – The below is the setup for that server
Then we need to modify the options in CLI
Next I changed my account to force me to change my password at next login – check this out.
There we go! once I change my password to something that meets the complexity requirements of my organization it will allow me directly into the VPN – and change my password.