Thursday, April 5, 2012

Data Backup (not recovery)

I am a great believer in making regular data backups and I don't hold much stock in the concept of data recovery.

I am also not a great fan of the backup solutions that are offered by Microsoft or third parties. Using a "robust copy" such as Windows robocopy or Linux rsync you can make incremental backups that can protect terabytes of data in a manner that doesn't take hours.
Once you have learned the syntax of the commands it is easy to use and you don't have to worry about loosing data to a drive going "bad".

In my experience you can predict when a drive is likely to fail and in situations where you do something like drop your laptop you will soon learn to make the backups that I describe. In addition, I am also of he opinion that you should not have your backup on a drive that you boot a computer. You can have copies of that data but when the boot drive goes bad so does that precious data.

I currently have up to about 4T Bytes of data and I cannot store this on a single drive in any case. My "backup and use" drives currently comprises of 2 * 2T drives plus 2 * 1.5T drives. The "pairs" are "working" and "backup" copies. The drives are mirrored using Windows robocopy.

As long as I remember to run the backups the incremental copy can take a matter of minutes.

As can be seen the copy of 734M of media took just over 28 min
The /MIR switch creates a "mirror" and if no changes are made to the 2 drives:
This is the same robocopy command as the copy above with no additional media
The mirror command only took 3 seconds - compare this will copying a 2T drive in its entirety which could take 12 to 24 hours!

In addition, should the connection between the drives and the computer or network be interrupted the process will restart where it left off.

1 comment:

igor said...

What is it with these companies that claim to provide a solution to your dalliances with regard to making backups up front?