Disk Partitions under Sys V/386

[Piercarlo Grandi]

In article <598 at gistdev.UUCP> joe at gistdev.UUCP (Joe Brownlee) writes:

   I have a 6386 WGS on which I am about to install UNIX System V/386, version
   3.2.  The machine has two disk drives: a 72 MB and a 40 MB drive. I wish to
   place partitions on the disks such that /, swap, and a /usr2 partition are
   on the first disk (the 72 MB), and /usr is on the 40 MB.  OK, so far.

Actually you want to have the 40 meg disc with '/,/tmp,/usr' as
the first disk, and the 72 meg one with 'swap,/usr2' as the
second disc, for good performance reasons.

   The problem seems to be that when you are installing UNIX, the installation
   software only knows about the first disk.

You can do all you want if you do not use the automatic install
to the end. Just have it create the mini root on the hard disc, of the
size you want it to have; lie to the disk setup program so that the root
partition comes out of the right size.

Once you have booted the hard disc with the mini root, edit /etc/partitions
in the way that suits you most, adding in the second hard disc, and
partitioning the disc as you best please. I would advise having the following
setup:

	disc0:
		root: 10 megs [0s1]
		/tmp: 4 megs [0s2]
		/usr: 26 megs [0s3] (you will want to put here /usr/local)

	disc1:
		swap: 8 megs [1s2]
		/usr2: 64 megs [1s3]

For every partitions you have to invoke 'mkfs' and 'labelit'; a
good guide to the number of inodes to configure with mkfs, is 1
for every 10 sectors, i.e. just drop the last digit from the
number of sectors, and use that as the number of inodes, e.g.
'mkfs /dev/rdsk/1s3 128000:12800 x y'.

Notice that the kernel you are running will use by default '0s2'
as the swap device; delay setting up the '/tmp' partition until
you have added the line 'swapdev=hd(18,0)' to
'/etc/default/boot'. If your system crashes on this, you must
edit by hand '/etc/conf/pack.d/kernel/space.c' and set the
'nswap' variable to the number of sectors in '1s2'.

	Note: having the swap partition on a disc that is not the one
	holding the binaries (that is, the root and '/usr' partitions)
	may be almost as big a win as not having '/tmp' on the same disc
	as your most frequently edited/compile files.

Once you have your filesystems made and labeled, just mount them and use
the package installation script to load the rest of the root partition and
'/usr', and the optional components (SDS, ETI, etc...).
--
Piercarlo "Peter" Grandi           | ARPA: pcg%cs.aber.ac.uk at nsfnet-relay.ac.uk
Dept of CS, UCW Aberystwyth        | UUCP: ...!mcvax!ukc!aber-cs!pcg
Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg at cs.aber.ac.uk