I’ve recently been experimenting with AD Authentication on Ubuntu 18.04 using the guidence on the Ubuntu Documentation (Reference below).
Coming from a Windows background I was used to users on laptop being able to login to a Windows client they had logged into previously even without having access to the corporate AD environment (common laptop/notebook workflow) however, noticed that on Ubuntu this wasn’t the case and off the network users couldn’t login at all.
One of the things that kept popping up was libpam-ccreds however, this didn’t appear to have any impact.
I then stumbled upon some information on SSSD indicating that credential caching as default is not enabled for SSSD and is literally as simple as updating sssd.conf with:
[domain/EXAMPLE] cache_credentials = true
After updating the file and restarting the SSSD service, all is sorted! #EasyWhenYouKnowHow