We hear a lot about single-instance storage; single-instance
backup. When you start backing up operating
system (OS) files, you will have the same .DLL, for example, on
each of your Windows servers -- you may have 100 servers. I
would say, if you have a small environment, I wouldn't worry too
much about it. But, once you start growing into a larger
environment,
you probably should not back up OS files.
@24686 That said, the OS files should be protected, so we have
ghosting products. We have products that allow you to virtualize
some of your servers (e.g., VMware) where you can create a live
copy of your system living somewhere else. These allow you to not
back up your operating system files -- you don't want to have to do
this backup. However, you want to back up your system objects such
as a Windows registry because there's a lot of settings in there
that you don't want to reapply.
But as far as the OS files -- the ones that are installed -- I
would say get some system images that are updated frequently as
your operating system changes, and keep the OS content out of your
backup loop. Your backups should really protect your dynamic
application data and not the OS files. You can have
terabytes and terabytes of data that is
stored on
tape, and when you try and restore your
systems, typically you're going to rebuild an OS and then
restore your data. So, why did you back up these OS files in the
first place?
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