10 pounds in a 5 pound bag..

[doelz at urz.unibas.ch]

In article <9008011308.AA17269 at avelon.lerc.nasa.gov>, 
fsfacca at AVELON.LERC.NASA.GOV (Tony Facca) writes:

>   Filesystem                 Type  blocks     use   avail %use  Mounted on
>   /dev/root                   efs   30360   25522    4838  84%  /
>   /dev/usr                    efs 1144503  382654  761849  33%  /usr
>   /debug                      dbg  196848   10224  186624   5%  /debug
> 

This is a partitioning which is generally undesirable. On our SGI as well 
as on the other mainframes I am responsible for it proved to be reasonable 
to create a partition /people in order to separate /usr - files which 
don't need to be backed up from those who do need occasional save sets. 
Secondly, desipte the fact that there should be no disk quota on /tmp, 
it is necessary to create a /tmp partition which is , let's say, 100 megs.
This /tmp then can easily be maintained but won't overflow the /usr. 
You could also create more partitions for software, or different working 
groups. On a bsd machine I need to keep as optimal as possible, 
I even have a second root partition which is mirrored to the root 
partition where unix lives on. In case of trouble, I boot from 
the other root disk. My df (with modified /root) on the SGI looks as follows: 

Filesystem                 Type  blocks     use   avail %use  Mounted on
/dev/root                   efs   33460   26550    6910  79%  /
/dev/dsk/ips0d1s6           efs   43200   34494    8706  80%  /usr2
/dev/dsk/ips0d1s5           efs   79800   75678    4122  95%  /biozen
/dev/dsk/ips0d1s3           efs  235600  232857    2743  99%  /profi
/dev/dsk/ips0d1s2           efs  193800  185380    8420  96%  /software
/dev/dsk/ips0d1s1           efs   38000   37996       4 100%  /profi2
/dev/dsk/ips0d0s5           efs   50470   14730   35740  29%  /tmp
/dev/dsk/ips0d0s6           efs  305760  248249   57511  81%  /usr
/debug                      dbg  255200    8704  246496   3%  /debug

Concerning the "/ is full" pity: You can easily softlink a reasonably 
large file to /usr if this one is not needed at boot time before the 
partitions other than / are mounted (meaning that 'unix' is not a good 
example). 

Concerning the repartitioning: If you are daring enough and have reliable 
backups on hand, you could try to use the standalone fx in order to 
modify partition sizes and/or create new ones. Take care of the different
disk types, because blocks and cylinders are different dependent on the 
model you are entering in the first questions of fx. There is an article 
in a recent 'pipeline' issue about using fx. A caveat is to be considered 
here: Though fx is capable to have up to 9 partitions, SGI is using 
only 0, 1, 5 and 6 in the /dev/dsk and /dev/rdsk. This means that you 
need to create new special files (see mknod(1M)) in order to use partition 
2 or 3. You shouldn't touch 7, 8, or 9 because these partitions are special. 


Hope this helps, 
Reinhard