At 7:11 PM +0200 5/6/03, Reinier Jonker wrote:
>After an unexplanatory freeze on my Quadra 840 running 1.6R, I had 
>to manually reset the machine. Since this has happened once or twice 
>before, I expected fsck to be run and be finished in half an hour. 
>Unfortunately, fsck immediately exited reporting:
>
>dev/rsd1a: BAD SUPER BLOCK: VALUES IN SUPER BLOCK DISAGREE WITH THOSE IN FIRST
>ALTERNATE
>
>The filesystem appeared to function normally. I read the man page 
>for fsck (couldn't find anything) and then the one for fsck_ffs. I 
>found out fsck_ffs -d would give me diagnostic reports. I saw some 
>values were replaced by noughts in the alternate super block.
>
>I can't get fsck(_ffs) to repair this problem. Help! ;-)
>Thanks very much in advance.

fsck has an option to force it to use a specific superblock. 
Probably you want to fsck the disk using the primary superblock since 
that appears to be OK.  Maybe if you do that it will automatically 
update the alternates.

If not there ought to be a way to force the alternates to agree, 
otherwise why have them?  I will admit I don't see how to do that 
from the man pages though.
-- 
The opinions expressed in this message are mine,
not those of Caltech, JPL, NASA, or the US Government.
Henry.B.Hotz@jpl.nasa.gov, or hbhotz@oxy.edu