Wednesday, May 11, 2011

Be paranoid about your data!

You can never be too paranoid about the potential for technology do "disappear" your data. Whether it be business or personal there is much of our data that we just cannot afford to lose.
  • Want to reconstruct the contact list you've been using for 20 years and the new application you installed just scrambled?
  • How are you going to explain losing the only photos of "X"...?
Having data on your computer and one other copy on a single other disk - that you back up when you remember - is not a backup strategy. Why not? Your drive fails or you need a file you remember you deleted a while ago - and you go to the backup disk and find...
  1. it's corrupt, 
  2. failed to fully backup last time, 
  3. is a backup of the files after you deleted your precious desired files.
  4. all of the above...
Backing up to optical media I have found to be very unreliable - and quite incapable of dealing with the scale of data we have on our disks. So backing up to hard disks is essential - but they have to be checked / refreshed over a period of years since they are also not permanent.

Some guidelines
  1. Data is not really backed up unless it is in two places in addition to your working area
    • This means at a minimum, two separate physical devices
    • Ideally, the devices will be at two separate physical locations (see below!)
  2. If at all possible ensure all your data storage systems are RAID i.e. at least mirrored drives. (There are more sophisticated configurations). By this I mean your working computers and the storage you are backing up to. If the working computer is a laptop, this is generally not possible unfortunately
  3. Automate the process; the road to data hell is paved with good intentions to do that backup. 
  4. Ideally, use two different software solutions to backup critical data
The basic logistics

I don't advise buying single USB connected hard drives - they are cheap but require manual intervention and are a single point of failure. Do buy NAS (Network Attached Storage) units that take at least 2 drives and plug in to your network. They cost from around $200 and upwards with no drives. Buy the requisite number of large as cost-efficient drives to fill it. 2TB drives are below $100/unit...
There are many solutions, most will take snapshots of your data at regular intervals, some back it up continuously. The former can "miss" changes that have happened between backups, but can be very efficient. I favour the latter for user data and for people with just one software package, for disaster recovery as well. (Though it's slower in data recovery than snapshot approaches; just hope you don't need to do a lot of recovery!). Specific recommendations are:
    • For Mac's - use Apple TimeMachine
    • For PC's - use Genie TimelinePro
 Both these allow you to "wind back" the view in your data directories and recover earlier versions or lost files going back as long as you've been running the software (and have backup space on your NAS - which is the reason to have lots of storage in your NAS).
  1. Plug the NAS unit into your local area network (LAN). RTFM to learn how to set up the storage to be accessible from any computer on your network; wireless or wired. A "freebie" benefit is that this also provides shared storage for swapping files between computers and storing music and videos that can be streamed to all computers and many TV's, HiFi's and other media tech. The NAS will also have a way of notifying you via email if the unit is not working. Set this up! It will typically also allow you to set up a schedule so it powers down overnight; a good idea since it saves power and ensures the unit is clean booted every day.
  2. Install a (licensed!) copy of the backup software on every computer and laptop, and "point" it at your NAS.
  3. The minimum is to set this up to continuously backup each machine including disaster recovery. Again, RTFM to ensure this is how you have set it up. It is dead easy. The software will also have a way of notifying you via email if the backup is not working. Set this up too! There will also be a way to create a disaster recovery disk or USB. This you will need if a computer completely corrupts itself and needs to be rebuilt. The disk or USB can then be used to reboot the computer and restore it from the backup automatically. It's no good realising you need this after the computer is dead...
  4. Check you know how to recover both individual files and how to run the disaster recovery disk/USB. Reading the manual is not enough - you have to do it! 
  5. Regularly check that the software is running on each of the target machines and that the NAS has ample free space.

    This basic approach will give you real security against single drive failures. I strongly recommend in addition, using snapshot backup software (like Norton Ghost or Windows Backup which is free) to create images of your system to another backup storage - in addition to your NAS. Ideally this should also be automated, but manual is OK too if you have done the above. For real data security, see the most recent post.

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