If you haven't been stuck in Antarctica for the last six years, you'll know that there's been a huge profusion of linux distros, as your regular visits to this site and distrowatch.com will confirm.

The trouble comes when you're not satisfied with just reading about them, but you actually want to try them out. In consequence you will inevitably become a serial hard disk partitioner.

Now, let it be said, there are several things you need to look out for, before carving up your hard disk like a Japanese Steakhouse Chef. However, I'm only going to mention one, because chances are, you know most of the others already.

The issue regards primary and logical partitions, and how it's important that you control that aspect from the very start. If your filesystem happens to slip from a primary to a logical partition because of some of your endless partitioning, well ... you will not be able to read it. And the venerable fsck and tune2fs won't help you too much either.

I say all this because it happened to me. I was/am a trigger happy distro fanatic. I wanted/want all of them bootable on my sturdy laptop harddisk. You might ask why. Well, for fun, F-U-N, fun. After all, that's the distrowatch slogan, "use linux: put the fun back into computing" (actually, this isn't entirely true, some of the stuff I install is seriously useful... can't divulge right here though).

Anyhow, what happened was, is .. that I had a hard disk with about 12 partitions, the first three being primaries, the fourth being extended, so I ¡could add a bunch of logical partitions, and not get stuck with Intel's four partition limit.

Now some of my primary partitions were quite big, so later on I decided to slim them down a bit (usually using cfdisk, but I think fdisk is similar). In doing so, I was increasing the number of primary partitions, which, can not be more than 3.

This process would cause certain primary partitions to be "relegated" to logical status, The problem is then, these - erstwhile primary - partitions - now logical - can't seem to be read anymore.

That can be particularly worrying. In my case I had a load of un-backed-up files, which I could no longer read.

I spent some time on these forums, and reading, and experimenting before I came up with a cunning plan. Rather than study the structure of ext2 filesystems in depth, or learn more about the tune2fs or e2fsck commands, I would ... wait for it, retrace my steps, and reverse the process.

In other words, if converting a partition from primary to logical made the filesystem unreadable, why not convert the logical partition back into a primary partition?

Actually, it was quite a troublesome plan, as it demanded my sacrificing some earlier installs, but at least it was all stuff I had backed-up. I don't mind deleting stuff I have backed up, although re-installing can be a pain sometimes.

However, this "reverse" process actually worked. Once the filesystem was on a primary partition (again), it could be read and written with no problems.

I also found out was that IDE drives can take a full logical 64 partitions. So I've decided to only have one or two primary partitions, and keep the majority of them logical. That way the filesystems on them can always be readable, no matter how often I take a knife to my hard-disk.

Now that's only one piece of advice, written, as you can see, to entertain as well as enlighten. So my motto now is:

"when adding new linux partitions, go for logical, not primary" Keep it in mind thou worthy distro-addicts.