Hi. On my computer at home, I have 800 GB of data. My external storage is
1000 GB and I use Acronis from your recommendation. I have a backup of my
computer and then weekly, I do differential backups, but the storage is becoming
full. So I had to delete the external storage and start again. So for five hours,
if my computer broke, I was going to lose everything. Is the only solution to
buy a bigger external storage?
In this excerpt from
Answercast #11, I look at the issue of storing backup files, explain
different methods of storing backups, and look at what might be the easiest
solution to a large data problem.
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A bigger hard drive?
It’s not the only solution, but it is certainly a solution and it might even
be the easiest solution.
There are a couple of different approaches you can take.
One is to crank up compression.
Acronis and similar backup tools usually have the option to compress the
data that they’re backing up. The default is typically what I would call
moderate compression. They can usually be turned up so that they’ll compress
the data a little bit more. The actual backup copy then would take up less
The cost is that the backup might take a little bit longer because you’re
actually asking the CPU to do more work as the backup happens.
Another option is: instead of using differential backups, use incremental
The difference is actually simple. You started out with a full backup (which
I assume is the five hours initial backup that you started with), every backup
thereafter can be either incremental or differential.
- Incremental says, “Save the changes since the previous backup.” Those are
typically fairly small or small in comparison.
- Differential backups are backups that include everything that changed since
the full backup was taken.
A differential backup would get bigger every time you take it until you run
out of space. An incremental backup would actually vary in size because its
size will depend only on what has changed since the previous incremental backup.
So, that’s another option.
Certainly getting another hard disk is a very simple option.
Creative system images
The other approach (I’m a little reluctant to go this way) is to consider
whether or not everything on your primary hard drive needs to be backed up or
needs to be backed up all the time. One solution is to take a system image – an
initial system image – and save that in a different place, or on a different
platform, and then selectively choose what to backup on a more frequent
I suggest that only because it’s certainly a possibility. I’m reluctant to
suggest it only because you do run the risk of not necessarily backing
everything that you wanted to.
Less frequent backups
Another approach, of course, is to do less frequent backups. In fact, I ran
into this myself several years ago, I had Acronis doing a full backup followed
by nightly incremental backups.
My hard drive (my backup drive) got full. So, I made a choice to do
incremental backups every other night instead. The same could apply with a
solution that still uses your differential backups.
So, there are a lot of different approaches to solving this particular
problem. You can reconfigure your backup to do things a little bit
Cost of a hard drive
By far, the simplest, (even though you already have a pretty big drive at a
terabyte) is to go out and get another hard drive. Get one that is as
large, and come up with a way to spread the backup across the two drives
(which is not necessarily an easy thing to do). Or go out and get yourself a new
even larger one.
I believe they just released a three terabyte for not that much. I know that I have
series of two terabyte drives in my basement right now.
So there are definitely some easier options there with respect to simply
getting larger hard disk. In all honesty, given the price of hard disks these
days, that’s probably the easiest and safest way to go.