df -k reports incorrect disk space on Sun Ultra-1 running Solaris 2.5.1

1. df seems to report incorrect space

I can't figure this out.  I've got 3 disks, all of which don't show the
correct space as reported by df. i.e. the used+avail does not add up
to the total.

Here's what I have

My newest drive was put in today /c0t2d0s2 with 1.96G as reported in
format.dat's verify (below). As soon as I had installed this disk, the df reported 1.9G total and
1.77 avail -- 200 Mb seems missing -- this can also be seen here since
the used + avail for the last entry does not add up to the avail. capacity

What gives?

Thanks
Suresh

------------------------------------------------------------------
As reported by df:

Filesystem            kbytes    used   avail capacity  Mounted on
/dev/dsk/c0t3d0s0      47977   34398    8789    80%    /                  
/dev/dsk/c0t1d0s6    1832578 1553465   95863    94%    /usr              
/proc                      0       0       0     0%    /proc              
fd                         0       0       0     0%    /dev/fd            
swap                  159056     364  158692     0%    /tmp              
/dev/dsk/c0t3d0s1     114877   44233   59164    43%    /opt              
/dev/dsk/c0t2d0s2    1933463  344951 1395172    20%    /disk2            

As reported by format's verify on disk2

Part      Tag    Flag     Cylinders        Size       Blocks
  0       root    wm       0 -   72       64.37MB    (73/0/0)
  1       swap    wu      73 -  218      128.75MB    (146/0/0)
  2     backup    wu       0 - 2277        1.96GB    (2278/0/0)
  3 unassigned    wm       0               0         (0/0/0)
  4 unassigned    wm       0               0         (0/0/0)
  5 unassigned    wm       0               0         (0/0/0)
  6        usr    wm     219 - 2277        1.77GB    (2059/0/0)
  7 unassigned    wm       0               0         (0/0/0)

--
Suresh Rajagopalan

Live life -- Rollerblade!

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