AKA Schrödinger’s Backup. Until you have successfully restored from a backup, it is just an amorphous blob of data that may or may not be valid.
I say this as someone who has had backups silently fail. For instance, just yesterday, I had a managed network switch generate an invalid config file for itself. I was making a change on the switch, and saved a backup of the existing settings before changing anything. That way I could easily reset the switch to default and push the old settings to it, if the changes I made broke things. And like an idiot, I didn’t think to validate the file (which is as simple as pushing the file back to the switch to see if it works) before I made any changes.
Sure enough, the change I made broke something, so I performed a factory reset and went to upload that backup I had saved like 20 minutes prior… When I tried to restore settings after the factory reset, the switch couldn’t read the file that it had generated like 20 minutes earlier.
So I was stuck manually restoring the switch’s settings, and what should have been a quick 2 minute “hold the reset button and push the settings file once it has rebooted” job turned into a 45 minute long game of “find the difference between these two photos” for every single page in the settings.
That’s always just one of the worst feelings in the world. This thing is supposed to work and be easy and… nope. Not there. It’s gone. Now you have work to do. heh
I remember back when I first started seeing a DR plan with three tiers of restore, 1 hour, 12 hours or 72 hours. I knew that to 1 hour meant a simple redirect to a DB partition that was a real time copy of the active DB, and twelve hours meant that failed, so the twelve hours was a restore point exercise that would mean some data loss, but less than one hour, or something like that.
I had never heard of 72 hours and so raised a question in the meeting. 72 hours meant having physical tapes shipped to the data center, and I believe meant up to 12 (though it could have been 24) hours of data lost. I was impressed by this, because the idea of having a job that ran either daily or twice daily that created tape backups was completely new to me.
This was in the early aughts. Not sure if tapes are still used…
We used to say Raid is not a backup. Its a redundancy
Snapshots are not a backup. Its a system restore point.
Only something offsite, off system and only accessible with seperate authentication details, is a backup.
3-2-1 Backup Rule: Three copies of data at two different types of storage media, with 1 copy offsite
AND something tested to restore successfully, otherwise it’s just unknown data that might or might not work.
(i.e. reinforcing your point, no disagreements)
AKA Schrödinger’s Backup. Until you have successfully restored from a backup, it is just an amorphous blob of data that may or may not be valid.
I say this as someone who has had backups silently fail. For instance, just yesterday, I had a managed network switch generate an invalid config file for itself. I was making a change on the switch, and saved a backup of the existing settings before changing anything. That way I could easily reset the switch to default and push the old settings to it, if the changes I made broke things. And like an idiot, I didn’t think to validate the file (which is as simple as pushing the file back to the switch to see if it works) before I made any changes.
Sure enough, the change I made broke something, so I performed a factory reset and went to upload that backup I had saved like 20 minutes prior… When I tried to restore settings after the factory reset, the switch couldn’t read the file that it had generated like 20 minutes earlier.
So I was stuck manually restoring the switch’s settings, and what should have been a quick 2 minute “hold the reset button and push the settings file once it has rebooted” job turned into a 45 minute long game of “find the difference between these two photos” for every single page in the settings.
That’s always just one of the worst feelings in the world. This thing is supposed to work and be easy and… nope. Not there. It’s gone. Now you have work to do. heh
Always a fun time when technology decides to just fuck you over for no reason
But the backup software verified the backup!
Schrödinger’s backup
Fukan yes
A LTO drive with a non-consumer interface?
We still say that.
I remember back when I first started seeing a DR plan with three tiers of restore, 1 hour, 12 hours or 72 hours. I knew that to 1 hour meant a simple redirect to a DB partition that was a real time copy of the active DB, and twelve hours meant that failed, so the twelve hours was a restore point exercise that would mean some data loss, but less than one hour, or something like that.
I had never heard of 72 hours and so raised a question in the meeting. 72 hours meant having physical tapes shipped to the data center, and I believe meant up to 12 (though it could have been 24) hours of data lost. I was impressed by this, because the idea of having a job that ran either daily or twice daily that created tape backups was completely new to me.
This was in the early aughts. Not sure if tapes are still used…