Not a problem.

For each file system, there's a bit of "reserved for root" space.  This
varies from about 5% to 10% of the total space, and only processes with
euid=0 can allocate space in this reserved area.  This is ensure that
system activities, like syslog, can continue to work at least for a
while.

df shows the amount of space available to non-euid0 processes.  In your
case, the total disk is 990582K in size, and only 961902K used.  So
there's really 28680K available.  But, since something has "intruded"
into the reserved space, there's only -20850K available for non-root
processes!

On Sun, 31 Jan 1999, Jaromir Dolecek wrote:

> 
> I run out of disk space the  other day and df output looked a bit wierd:
> 
> dolecek~ > df
> Filesystem  1K-blocks     Used    Avail Capacity  Mounted on
> /dev/wd0a      990582   961902   -20850   102%    /
> /dev/wd0e      708411   556513   115303    82%    /usr/emul/linux
> kernfs              1        1        0   100%    /kern
> procfs              4        4        0   100%    /proc
> 
> This shouldn't happen, should it ?
> 
> -- 
> Jaromir Dolecek <dolecek@ics.muni.cz>	http://www.ics.muni.cz/~dolecek/
> -------------------------------------------------------------------------
> It is better never to have been born.  But who among us has such luck?
> One in a million, perhaps.
> 

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