fsck on a mounted fs as read-only

[Nikos Vassiliadis]

On 5/31/2012 12:19 PM, dmitry at zhigulinet.ru wrote:
> Good afternoon.
> Could not tell whether you can run fsck on checking mounted file system as read-only, if prior to that with which the parameters
>
>
> ftp # mount
> ...
> / dev/aacd0 on / var / ftp (ufs, NFS exported, local, read-only)

Could you copy & paste the exact lines?
The "/ dev/aacd0 on" & "on / var / ftp" parts make no sense to me.
It should be:
some_dev on some_dir (ufs, NFS exported, local, read-only)

>
> Launched with these parameters and this is what gives
>
> ftp # fsck -yf / dev/aacd0
> ** / Dev/aacd0 (NO WRITE)
> ** Last Mounted on / var / ftp
> ** Phase 1 - Check Blocks and Sizes
>
> As I understand it does not fix the fsck filesystem.
>

fsck filesystem_goes_here
for example "fsck /dev/ada0s1a"
or
fsck mount_point_goes_here
for example "fsck /"

You are probably trying to fsck the wrong device...

Rebooting to single user and fscking the RO mounted / fs works as usual.
Please provide more info.

HTH, Nikos