I don’t know if it is the „correct“ way but I do it the other way around. I have a server and a backup server. Server user can‘t even see backup server but packs a backup, backup server pulls the data with read only access, main server deletes backup, done.
For an organisation hosting as many companies data as this one I'd expect automated tape at a minimum. Of course, if the attacker had the time to start messing with the tape that's lost as well but it's unlikely.
Fundamentally there's no need for the user/account that saves the backup somewhere to be able to read let alone change/delete it.
So ideally you have "write-only" credentials that can only append/add new files.
How exactly that is implemented depends on the tech. S3 and S3 compatible systems can often be configured that data straight up can't be deleted from a bucket at all.
The 3-2-1 backup strategy: "Three copies are made of the data to be protected, the copies are stored on two different types of storage media and one copy of the data is sent off site."
Any redundant backup strategy uses both. They both have inherent data loss risks. Local backups are great, but unless you store them in a bunker they are still at risk to fire, theft, vandalism and natural disasters. A good backup strategy stores copies in at least three locations. Local, off-site and the cloud. Off-site backups are backups you can physically retrieve. Like tapes stored in a vault in another city.
Now that you mention fucking incompetence, I need to verify my 3-2-1 backup strategy is correctly implemented. Thanks for the reminder, CloudNordic and AzeroCloud!
Danish hosting firms CloudNordic and AzeroCloud have suffered ransomware attacks, causing the loss of the majority of customer data and forcing the hosting providers to shut down all systems, including websites, email, and customer sites.
I feel really bad for everyone involved - customers and staff. The human cost in this is huge.
Yes, there's a lot of criticism of backup strategies here, but I bet most of us who deal with this professionally have knowledge of systems that would also be vulnerable to malicious attack, and that's only the shortcomings we know about. Audits and pentesting are great, but not infallable and one tiny mistake can expose everything. If we were all as good as we think we are, ransomware wouldn't be a thing.
I think that people generally overestimate how much money tech companies like this one actually make. Their profits are tiny. A lot of the time, tech companies run on investment money, and can't actually turn a profit. They wait for the big acquisition or IPO payday. So if you think you're actually gonna get 100k off them, good luck. Sometimes they're barely keeping the lights on.
Martin Haslund Johansson, the director of Azerocloud and CloudNordic, stated that he does not expect customers to be left with them when the recovery is finally completed.
Sounds like they had all their backups online, instead of keeping offline copies. It's a reminder that everyone needs at least one backup that isn't connected to any computer. It's also a reminder that "the cloud" should not be the only place you keep your data, because hosting providers are targets for this stuff and you don't know how careful they are.