Remounting a drive as read/write crashes the system and no dmesg.boot

[Mel Flynn]

On Thursday 20 August 2009 18:40:27 Scott Schappell wrote:
> On 8/20/2009 7:36 PM, Scott Schappell wrote:
> > On 8/20/2009 4:31 PM, Mel Flynn wrote:
> >> http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/ker
> >>neldebug.html
> >
> > OK, /backup was mounted read only, I did the following
> >
> > umount /backup
> > mount -o rw /backup
> > [root at arthur ~]# dd if=/dev/zero of=/backup/testfile bs=1024
> > dd: /backup/testfile: end of device
> > 21122+0 records in
> > 21121+0 records out
> > 21627904 bytes transferred in 2.215991 secs (9759924 bytes/sec)
> > [root at arthur ~]#
>
> As of now, the dd command above has not crashed and it's past 3 GiB,
> using the mount -u -w syntax versus unmount, mount -o rw.
>
> This is puzzling.

I agree. These errors make no sense to me, which leads me to drive cable or 
physical memory problems, perhaps filesystem corruption. Since you have plenty 
of space on /home, is it possible for you to move whatever's on /backup to 
/home, then newfs /backup? Of course you could try fsck -y /backup in single 
user, but with these weird errors, I trust the filesystem on that disk as far 
as I can throw it.
-- 
Mel