Hetzner Cloud – Data loss incident
Data loss incident (snapshots)
Dear Customer, Unfortunately, we have to inform you that there was a data loss incident that affects a small amount of your snapshots on Hetzner Cloud. All snapshots you create are stored on our highly available storage systems. The snapshot contents are distributed over multiple internal servers and data is stored in a way that allows up to two separate disks to fail without impacting data integrity. This means the snapshot can still be accessed, even if two disks fail at the same time. Due to a recent, very unfortunate series of events in one of our clusters, multiple disks failed in short succession and caused a small number of snapshots to become unavailable. We immediately tried to recover the affected snapshots but unfortunately the data is lost and we have exhausted all our options.
Affected snapshots in your account: XXXXXXXXX
The snapshots have been removed from our system as they are no longer accessible. We sincerely hope this doesn’t cause too much trouble for you; we know losing data is the worst-case scenario. Also, we have added 20€ as Cloud Credits to your account (valid for one year). While we know that this will not bring back your data, we still hope that you will accept the gesture. In response to this we will re-evaluate our snapshot cluster data replication strategies as well as our strategies for replacing disks and rebuilding redundancy after replacement.
Best Regards, Hetzner Cloud
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It's really odd to see so many complaining when yesterday a thread about Atlassian was asking for precisely this type of communication.
They communicated what went wrong, how it happened (in a nutshell), apologized and stated how they're planning to do better.
They even threw in 20€ which when compared to the pricing of their snapshot storage is more than fair.
Shit happens, things go wrong. If you lost very important data because you only stored it in one location, then you're equally at fault. Especially when taking into account that they are a rather cheap service.
What more do you want?
Anybody have more color on the nature of the "recent, very unfortunate series of events in one of our clusters [such that] multiple disks failed in short succession"? What kind of "events"? A failed climate-control system? A berserk employee with a sledge hammer? Russian hackers? The Spanish Inquisition?
It seems odd that they'd be quite so vague and circumspect about it. Why not just say what it was, so we're not all left to speculate, perhaps for the worst?
There is no reason to rely on "triple replication" for data integrity. This has long been a solved problem. An appropriate erasure encoding can reduce the probability of loss ~ten-fold while consuming physically less space (i.e. 2x worth of replication). Companies forego this technology because they feel confident in their operational ability to address failures quickly and competently. That's what we're relying on for data integrity, not the math.
Folks, remember the 3-2-1 rule. IMO, it’s still extremely relevant, even in today’s cloud-centric world.
For data you can’t afford to loose, please, for the love of $ {DEITY}, don’t store it with just one vendor. You never know what happens.
https://www.backblaze.com/blog/the-3-2-1-backup-strategy/ ↗
I've never trusted cloud provider snapshots because it's just paying more for something that might fail outside of your responsibility.
I have a local backup box and a remote one and they both sync stuff in from rsync on a cron job from multiple servers. Works great. In case of catastrophic failure (Which has happened a few times), putting my eggs in more than one basket has been extremely successful.