[cogs]

But if you restore from backup aren't you going to restore the trojans? And if the trojans wipe the disks after x days of radio silence?

[AnimalMuppet]

If you restore the system from clean images (if you have them!), then you can restore the data (and only that!) from backups.

If...

[cogs]

Yes, its the clean images I'm wondering about. It might not be easy to find clean images that are compatible with separate data backups.

[AnimalMuppet]

The backups can be backups of the whole image. That's fine, as long as the file structure is still there, so that you can restore the data, but not the programs, and even more not the OS.

[cogs]

There's surely a lot of bespoke software in those core Govt systems. So they'll be trying to run a software image from months ago with yesterdays data. The success of that depends on how quickly the software has been changing.