Asynchronous Mirroring in Unix

One of the issues I’ve found with having lots of data is the fact that I’m worried that a hard drive will fail, and I’ll lose something important. Since I did have that happen earlier this year, I am now determined to not let it happen again. I’ve been focusing a lot on resiliency – making it so that there are no single points of failure. Since I have been collecting a lot of hard drives, I decided to put them to good use, and set up some data replication onto multiple drives.

You might ask, why not just set up a RAID5? Or, alternatively, why not buy a Drobo and be done with it? I hear the first one a lot, especially since I deal with RAID day in and day out for my day job. The main issue I don’t do either of these things is that I’m cheap! I want to be able to use all of the hardware I have without tossing out old stuff. On my server, I have the following drives:

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How To Set Up a Two-Way Mirror Between Mac OS X and Ubunt...

After my hard drive crash a few months ago, I’ve been a bit paranoid about losing data.   By “a bit” I mean I’ve been sticking copies of my data on different machines to make sure I have various copies in case another hard drive dies, or a computer gets fried, melting everything inside, or my house burns down… Oh wait, I don’t have that scenario covered….  Time to fix that!  What I want is the ability to copy my data to an offsite location, and keep the backup up to date.  The main thing I care about is my family photos.   I was talking to my cousin Dave, and he had the same issue.  He wanted access to my photos, as well as have an offsite backup copy of his family’s photos.  I thought of a solution.  What if we could set up a two-way mirror between his machine and mine, and keep it updated nightly?  That way if he sticks something in the directory on his machine and vice versa, keeping a live backup.  I began doing some research, and I found the tool — Unison.

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