splitting root partition into root, usr, var etc.

[Sven Hartrumpf]

Hi all.

We have some Linux boxes (SuSE 7.2 and 8.1) sitting around that do not have
separate partitions for /, /usr, /var etc. :

> df
/dev/hde3     ext2    9.8G  7.5G  1.9G  80% /
/dev/hde1     ext2     99M  9.7M   83M  11% /boot
/dev/hde4     ext2     26G   24G  1.3G  95% /home

(parted) print                                                            
Disk geometry for /dev/hde: 0.000-39266.718 megabytes
Disk label type: msdos
Minor    Start       End     Type      Filesystem  Flags
1          0.031    101.975  primary   ext2        boot
2        101.975   2157.165  primary   linux-swap  
3       2157.166  12401.740  primary   ext2        
4      12401.741  39260.412  primary   ext2        

1. To avoid/reduce critical data losses when the machine crashes without cleanly
   unmounting, such additional partitions are recommended. And from my own
   experience, this seems to be very true.  Is there a recommended partition
   scheme - in terms of partition contents (and filesystem types and maybe
   distribution on 2 disks and partition sizes)?

2. Has anybody tested/documented a safe method to split "/" in a way described
   above?  (Without reinstalling, of course.)

Greetings
Sven