Partitioning for multiple systems

[Michael David Crawford]

I have a machine I plan to use solely for testing.  I have FreeBSD 
8.0-CURRENT on it right now, and would like to add FreeBSD 7.2-RC2 as 
well as CentOS 5.3 Linux.

Presently I have three Master Boot Record primary partitions - "slices" 
in the FreeBSD parlance, if I understand correctly:

- A Linux slice to be used for CentOS' /boot
- A BSD slice subdivided into partitions that hold 8.0-CURRENT
- A big FAT slice (so to speak) meant to be split up for 7.2 and CentOS

A PC-style Master Boot Record can hold a maximum of four primary 
partitions, or it can hold three primaries and a single extended 
partition that is subdivided into logical partitions.

The geometries of the logical partitions aren't given in the MBR, but 
exist as a linked list.

I *should* be able to split that FAT slice up into a primary for 7.2 and 
an extended partition that will hold CentOS' other partitions; however:

In Googling about this, I have read some dire warnings about FreeBSD 
being unable to understand logical partitions; apparently installing 
FreeBSD *before* an extended partition will result in all your logicals 
getting trashed.  One is advised to put all the FreeBSD MBR partitions 
*after* the extended partition.

Is that the case?  Have you any advice for me?

One more thing: if it's possible, I'd like for the /home directory to be 
shared between both of my FreeBSD installations.  In a normal 
installation, there is a real /usr/home directory, with /home being a 
symbolic link.

If I'm running FreeBSD out of one MBR partition (or slice), can I mount 
a directory that's in a different one?

Thanks for your help!

Mike
-- 
Michael David Crawford
mdc at prgmr.com

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