2 Apr
2014
2 Apr
'14
12:30 p.m.
On 04/02/2014 09:24 AM, Glen Slick wrote:
# dd if=/dev/zero of=/dev/rra8a bs=512
write error: read only file system
2+0 blocks in
2+0 blocks out
#
Does it work if you dd from the rx33 instead of to it? Can you read the
entire disk doing that?
Yes, dd will read all 2400 blocks from /dev/rra8a.
I took a quick find/grep around in /usr/src/sys/.../*.c for EROFS, and
it wasn't immediately obvious where to patch; ufs_fio.c is definitely
not responsible...
| I vaguely remember making a minor modification somewhere in the kernel
source and rebuilding it when I wanted to dd an image to an entire disk.
There is some code
| somewhere that appeared to want to prevent write access to the
disklabel area. I'll have to see if I can find the details of what I did
there. -Glen
Thanks, I'll also look into it a bit further after work tonight.