How to login (at remote site) when primary DC is down

I was once asked this question which I could not find an answer to.

This is the scenario.

The primary Domain Controller is at Head Office. Remote office is connected to primary DC via internet link provided by third party. All desktop PCs at remote office is set to wipe credential caching when they boot. Local account login is disabled. There is no BDC/RODC at remote office.

If the next morning internet link goes down (at remote office) before people had a chance to turn on their PCs, what are the possible solutions to let people login to their desktops

Thanks Emon

Solution 1:

According to your specs:

All desktop PCs at remote office is set to wipe credential caching when they boot. Local account login is disabled.

There is no way, and that's the point. The only way would be to use some software to enable a local login on the desktops itself, but what's the point if the workstation probably won't have Internet, DNS or fileserver access?

Solution 2:

What is missing from the question is the business continuity plan. Which network connected applications are essential for business operations? How long of a downtime can be tolerated?

Users don't have AD auth, so they do not have desktops at all. Either get them in via a local user or fix the WAN.

And consider adding additional connectivity from a different provider. Cell data, or Internet connections of any kind.