> I've installed NetBSD 1.4.1 on a Dell box. There is 3000M space
> in the NetBSD partition. However, when I tried to download something
> (as a common user) to the disk, I was told "/: write failed, file system is 
> full" during the downloading. I checked the disk usage by "du -sk", and the 
> result is : 512692, which is about 512M. There should be plenty of space 
> left.
	[...]
> 8 partitions:
> #        size   offset     fstype   [fsize bsize   cpg]
>   a:   567441       63     4.2BSD     1024  8192    16   # (Cyl.    0*- 562)
	[...]
>   e:  4525920  1618848     4.2BSD     1024  8192    16   # (Cyl. 1606 - 
> 6095)

There are two types of partition here. There are the BIOS partitions
(which you can see with fdisk) and the NetBSD partitions (the ones that
disklabel report) which are partitions inside the NetBSD part of your 
hard disc (a BIOS partition).

Looks like you have filled up your / NetBSD partition which is a in the
disklabel output. Presumably your /usr partition is e. And also regular 
users homespaces are probably in /home which is in your / partition.

A possible work around is to move /home to /usr/home and make a symbolic
link so that /home points to /usr/home.
e.g. ln -s /usr/home /home

That way your regular users will have their home spaces in the biggest
NetBSD partition of the disc.

HTH,
-- 
Chris