[vox-tech] Re: Partition question

[Rick Moen]

Margo, if you don't mind my addressing your concerns only obliquely, it
seems to me you've run into some Core Truths about filesystems:

1.  DOS is balky about where it's willing to boot from.
2.  The IBM/Microsoft partitioning scheme we've all inherited on IA32
    architecture (commodity PCs) is inflexible.
3.  Drive letters (a la DOS/Windows) suck.
4.  Multi-boot problems will drive you crazy.
5.  Repartitioning tools, especially the "non-destructive" ones, 
    have limits as to what they can do.

Personally, I think that the most important tools to have around when
you're rearranging filesystems are (1) maintenance boot media such as an
LNX-BBC, Knoppix disk, or Tom's Root-Boot floppy, (2) a LAN, and (3)
another PC.  Given those, you can just copy any file trees you care
about across the wire to your spare PC[1], blow away the existing
partition table, make a new one with the desired layout, mkfs those
new filesystems, and then copy the files back across the wire.  Works
for Me<tm>.

But I carefully avoid having to cope with multi-booting problems (and
concur with Jeff Newmiller's views on that).  When you're running a
Linux-only system, you can move files around as desired, and need only
adjust /etc/fstab to accomodate changes of device-names (e.g., /dev/hda
becoming /dev/hdb, etc.).  And sometimes you have to refresh your
bootloader's data.  But that's it.

Throw DOS into the picture, and you must contend with the facts that (1) 
it's happy about booting only from the first primary partition on the
first physical drive, and (2) its apps are prone to breakage if drive
letters change because you reshuffled things.  Sometimes, you can repair
that breakage, e.g., by adding dummy devices in CONFIG.SYS to pad out
drive letter assignments, such that your CD-ROM doesn't fall from F: to
E: despite your removal of the partition that used to furnish D:.[2]

(As I said, drive letters suck.  Unix, of course, never had 'em.)


Quoting Margo Schulter (mschulter at calweb.com):

> This is an interesting scenario, and the shared /home idea is
> something that I hadn't considered -- and the symlink that you
> discuss.

Sharing /home among multiple (multiboot) Linux distributions is an idea
that seems as if it should work -- and it might -- but it also might
not.  The joker in the pack is your "dotfiles" within your home
directories.  Let's say Slackware has GNOME 2.2 packages installed,
while Gentoo has GNOME 2.4 ones.  Let's say, for the sake of
illustration, that the GNOME configuration files' format changed
incompatibly between 2.2 and 2.4.  Most such configuration is handled
within /etc, so you'd be all right for that, as each distro would have
its own /etc tree.  But a user's home directory might well have a
~/.gconf tree, a ~/.dia tree, ~/.gconfd, ~/.gimp-2.0, ~/.gnome,
~/.gnome2, etc., and various apps may be broken by trying to read
configuration data of either either a newer or older format than they
expect.

That is not an easily solved problem.

So, for that reason and others -- as Jeff said -- I tend to avoid
complicated multiboot configurations.  Personally, when I want to try
multiple distributions, I either try them consecutively, or on different
computers, or at least on different hard drives that I exchange
physically when I want to switch.

That is not to say that you can't come up with workable partitioning
schemes to run multi-boot.  People do it all the time.  But at a
minimum, I'd copy the data off to a second disk or host, and then
repartition using good ol' "destructive" partitioners, redoing the
entire disk map in so doing.

[1] For tips about doing so, see "Copying Directory Trees" on
http://linuxmafia.com/kb/Admin/ .

[2] See "Drive Letter Order" on
http://linuxmafia.com/kb/Legacy_Microsoft/ .

-- 
Cheers,     Founding member of the Hyphenation Society, a grassroots-based, 
Rick Moen   not-for-profit, locally-owned-and-operated, cooperatively-managed,
rick at linuxmafia.com     modern-American-English-usage-improvement association.