Hi there,

Recently I installed slack-current on an old box with a pair of 3.2GB HDDs,
today I changed my mind about the partitions and want to shrink /usr and
increase small FAT32 to ~250MB.

Temporarily convert the box to use an NFS mounted /usr during repartition
of one the small HDDs fitted. Note, a box will boot without /usr, but it
can be a pain if something you need is in the /usr tree after you deleted
it. I use reiserfs3. Currently I have:

root@pooh:~# fdisk -l /dev/hdc

Disk /dev/hdc: 3227 MB, 3227148288 bytes
128 heads, 63 sectors/track, 781 cylinders
Units = cylinders of 8064 * 512 = 4128768 bytes

Device Boot Start End Blocks Id System
/dev/hdc1 1 2 8032+ 4 FAT16 <32M
/dev/hdc2 3 66 258048 83 Linux
/dev/hdc3 67 130 258048 82 Linux swap
/dev/hdc4 131 778 2612736 83 Linux


/dev/hdc1 is there for old BIOS HDD geometry requirement, now I want to
make it 250MB as I've decided to install win98 and need a data partition.

hdc4 is /usr and hdc2 is /usr/local, I'll halve /usr/local size as well.

method
```````
Avoid reinstall! On a localnet server, create an NFS export:

root@deltree:~# cat /etc/exports
# See exports(5) for a description.
# This file contains a list of all directories exported to other computers.
# It is used by rpc.nfsd and rpc.mountd.

/home/share 192.168.1.0/24(sync,rw,no_root_squash,subtree_check)
/home/mirror 192.168.1.0/24(sync,ro,subtree_check)
#
/home/share 192.168.2.0/24(sync,rw,no_root_squash,subtree_check)
/home/mirror 192.168.2.0/24(sync,ro,subtree_check)
#
# export NFS mounted /usr for stinkpad laptop:
/home/hal/usr 192.168.1.30/32(sync,rw,no_root_squash,subtree_check)
# ditto for pooh
/home/pooh/usr 192.168.1.22/32(sync,rw,no_root_squash,subtree_check)
#

root@deltree:~# exportfs -rv
exporting 192.168.1.22/32:/home/pooh/usr <<== new export
....
reexporting later.mire.mine.nu:/home/share to kernel

On a root login to the target machine, copy the files across to the server:

mount deltree:/home/pooh/usr /mnt
rsync -avH /usr/* /mnt/ # this takes a while

edit /etc/fstab, comment out the local HDD and add the remote /usr:

root@pooh:~# cat /etc/fstab
# /etc/fstab for slackware-11 on pooh
#
/dev/hda2 / reiserfs defaults 0 0
/dev/hda4 /home reiserfs defaults 0 0
#/dev/hdc4 /usr reiserfs defaults 0 0
#/dev/hdc2 /usr/local reiserfs defaults 0 0
deltree:/home/pooh/usr /usr nfs hard,intr
#
/dev/hda3 swap swap defaults,pri=1 0 0
#/dev/hdc3 swap swap defaults,pri=1 0 0
#
/dev/cdrom /mnt/cdrom auto noauto,owner,ro 0 0
/dev/fd0 /mnt/floppy auto noauto,owner 0 0
#
devpts /dev/pts devpts gid=5,mode=620 0 0
proc /proc proc defaults 0 0
#
deltree:/home/mirror /home/mirror nfs noauto,hard,intr
deltree:/home/share /home/share nfs hard,intr
#

wait for /usr upload to server . . .

reboot

root@pooh:~# df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/hda2 258036 106872 151164 42% /
/dev/hda4 2128824 902220 1226604 43% /home
deltree:/home/pooh/usr
8224960 3854272 4370688 47% /usr
deltree:/home/share 8224960 3854272 4370688 47% /home/share

So /dev/hdc is no longer mounted and we still have /usr via NFS, do
the fdisk manipulation (I'm old fashioned, rebuild, zero then format
partitions before reuse -- don't trust these new-fangled resizing
tools

After that I'll copy the data from /usr to the new home in two passes,
/usr to /dev/hdc4, adjust /etc/fstab for /usr change and reboot, then
move /usr/local to dev/hdc2, via temp mounts on /mnt/, adjust /etc/fstab
to final version, done.

Grant.
--
http://bugsplatter.mine.nu/