On 2/11/24 03:14:49, William Kenworthy wrote:
[...]
It occurred to me fairly quickly after that press of RET that I
could have done well with a COW snapshot facility, something which
has been discussed at length on another recent thread. I even have
LVM on my machine for its RAID capabilities. But I've never
bothered before. I mean "I'm too careful", amn't I? ;-( At least
I do a weekly backup, though.
[...]
No, you don't need a snapshot system - you need a proper backup
system that stores the proper metadata. When I was experimenting
with snapshots (btrfs and moosefs) at different times I lost
everything a few times with filesystem corruption which meant I lost
the snapshots too.
Snapshots are NOT safe backups - treat them as a convenient copy ...
Snapshots are as reliable as the underlying file system. Here at CeBiTec
we use snapshots on several PB CephFS and ZFS with great success.
And yes, I completely agree with Alan, snapshots would have saved his
day as they provide excellent and cost efficient protection against
pilot errors.
Our users restore lost data from snapshots themselves in seconds, while
it usually takes several hours to restore data from tape. Snapshots
and tape backups complement each other perfectly and both strategies
provide means of protection the other lacks.
Cheers
Björn
