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Hello!
I am both a newbie and not a newbie. Relative to someone who's never seen the CLI, I know quite a bit -- that is to say, I know just enough to get me into trouble. That being said, I apologize in advance if this thread ranges far-afield.

The Problem:
I plan on installing several distros across numerous partitions and 2 hds. I have moderately old computer (P4), and both of the hds will be approximately 20Gs. Don't worry about saving Windows (shudder). I'm a MacHead, so the very idea of Windows is anathema to me.

My questions relate primarily to how to partition the hds -- what can be shared and what cannot.

I already have decided not to share a /home partition amongst the various distros. (I thank mugstar in another post for that

Code:

ln -s /data

idea). Instead, I can't find much info about sharing other partitions.

1. Can I share partitions like /tmp and /var, which seem to me just to fill with logging info or temporary crud you don't necessarily need or want to hold onto? I'm not running a web-server or anything, so I can't see a real reason for an isolated or complicated /var.

2. A tricker and confusing bit: can you share /usr or /usr/local? Now, I realize that this is just shear lunacy and heresy to some, but I don't really understand why a number of distro's can't share some common /usr or /usr/local space (they're all using the same programs, right?, only the individual .config files would change per /home distro, right?)

3. I know /swap can be shared, and I plan on doing just that -- on the outer partitions of the slave drive so that it runs a little faster (I read that somewhere, so correct me if I'm wrong). If I can share /tmp or /var, can I put those near /swap as well, since they're probably not filled with a huge amount of really important info? I realize that if /usr or /usr/local gets its own partition, it should be relatively large and located on the master drive -- that just makes more logical sense to me.

Ok, that was most of the abstract partition business. Now, down to the /boot partition. What exactly is in the /boot partition, anyway? The kernel ... the boot loader ... the MBR ... what? If it's the kernel, can that be shared across multiple distros? (because that would be both nifty and possibly weird)

Before I go any further, let me lay out my current partition plan (this is given that I'm uncertain about that whole /tmp /var /usr /usr/local business)

Code:

hda1 =>  /boot    /*  yes?  */

hda2 =>  /Gentoo

hda3 =>  /Fedora4 

hda4 =>  /Suse10  /* in a month or so */

hda5 =>  /data  /* storing all my shared files  */



hdb1 =>  /FreeBSD5  

/*  does this complicate things 

inordinately?  I read that GRUB should 

point to FreeBSD on the othe drive, and 

while I'm entirely unsure of how that 

works, I might be able to figure it out 

(any help would be greadly appreciated).  */

hdb2 =>  /Darwin8  /*  What can I say? I'm a mac fan */

hdb3 =>  /minix2    

/*  all these distros are 

really just so that I can learn 

about the underlying operating 

systems and their concepts  */

hdb4 =>  /var

hdb5 =>  /tmp

hdb6 =>  /swap

Is this reasonable, or am I just crazy for wanting to experiment so much?

On a related note, I want to know how to set the UID and GID during install (per distro info, if that's necessary, would be great) or resetting them after install (if that's even possible). What are reasonable UIDs and GIDs by the way? I'm not sure what I should change them to even if I have the chance to set them.

Oh, and what about a reiserfs file system for the whole thing? I've read that it's pretty good. Also, can I use reiserfs with the /boot partition, or must I use ext2?

Is this whole plan reasonable, or am I just trying to drown myself in distros?

All answers or suggestions are immensely apprectiated!
Thanks!