I look after an office with 20 PCs and a server, and we run weekly full
backups and daily incrementals. Backups are to a USB-attached hard disk, which
is taken off-site overnight. What I’d ideally like to do is carry out the
backup process over the internet, to a remote PC with the backup drive
permanently attached to it, to avoid physically transporting the drive. Full
backup is around 120GB of data, incremental is 5 – 10GB. What would you
recommend as the best method to achieve this? (using an internet hosted,
paid-for backup service is not an option – too expensive!!)
On-line or internet hosted backup services (the ones you’re avoiding for the
cost in your situation) are becoming very popular. They definitely have their
place, but they also make me uncomfortable.
And they make me uncomfortable for the same reasons and issues that you’re
going to run into with what you’re attempting to do.
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The problem you’ll run into is bandwidth.
Unless you have an incredible internet connection, the copy off-site will
take longer than the backup period. In the table below I’ve done a little
back-of-the-envelope math, and as you can see, a 120 gigabyte backup will take
over a week to upload at “traditional” T-1 or good DSL speeds. If you have a
VERY good internet connection – beyond the maximum of DSL rates, you’re still
talking a day to upload and that’s assuming perfect communications and 100% use
of the internet connection.
|Backup Amount||1.5Mbs (T-1 or “good” DSL)||10Mbs (basic ethernet LAN speeds)|
|120gig||7.5 days||1.1 days|
|10gig||15.2 hours||2.2 hours|
In my opinion across-internet types of backups really only make sense
you have an extremely fast internet connection
or the amount of data that you’re backing up can somehow be constrained to a
more reasonable amount.
In other words, across-internet backups just don’t make sense for full
backups, and they rarely make sense in incremental backups in an busy
full backups, and they rarely make sense in incremental backups in a busy
So what about those online backup services?
First, I’m sure that they’re doing everything as smart as they possibly can
to minimize the impact of bandwidth limits. I’m sure they compress whatever
they can, and that they copy only things that have changed, and that they use
your internet connection at what would otherwise be “idle” times – which for
many people is most of the time.
However, that doesn’t change the fact that a full backup is a heck
of a lot of data; much more than one would want to upload via any typical
So compromises must be made, and it’s those compromises that concern me.
The most typical compromise is to use an internet backup service to backup
only your data. This makes total sense, and is a great compromise, as long as
one huge issue is addressed. In fact, I do something very similar myself on
a semi-regular basis.
That one huge issue? How do you backup the rest of your system?
It’s an issue that’s very common when you choose to backup only your data,
regardless of the reason. The issue is simply this: what happens when you lose
something that isn’t part of what you backed up? An installed application,
perhaps, or even Windows itself? Your on-line data-only backup will not
That’s why I recommend on-line backups only as part of a larger
backup strategy that includes full backups to more traditional backup
To put it even more concretely, here’s what I do:
Every night important data is collected on one central machine. The other
machines are not backed up in any other way. This implies that if something
worst-case happens to them I will end up having to rebuild them from scratch.
Based on what they do and how they are used, this is an explicit choice I’ve
That central machine is actually my primary desktop machine. Full backups
are performed on it monthly, and incremental backups are taken nightly. I use
Macrium Reflect and back up to a NAS device on my network.
Also nightly, some particularly critical data is copied across the
internet to the computers at my wife’s business, and vice versa. Because of the
bandwidth issues this is a limited amount of data; something that can be copied
in just a few hours in the middle of the night. (And the primary computer there
is also doing monthly full and nightly incremental backups using
Acronis to an external hard drive.)
Once a month a larger collection of data is assembled, compressed and
encrypted, and uploaded to an off-site server. This is about 2.5 gigabytes of
data, and takes several hours to upload.
As you can see, remote backup can be a part, but only a part, of a
larger backup strategy. I strongly recommend off-site backup of some sort, and
it’s one approach to that. However, that doesn’t remove the need to do an
explicit and well-thought out backup of full systems and data.