Re: After crash, / comes up mounted read-only, but in multiuser; mfs /tmp?

John Baldwin wrote:
> On Friday 02 December 2005 08:33 am, David Xu wrote:
> 
>>Robert Watson wrote:
>>
>>>While testing the new DRM update (went badly :-), I crashed my system
>>>and had to power cycle it.  When it came back up, not surprisingly,
>>>the file systems weren't clean.  When I reached a login prompt, I
>>>logged in to modify /etc/rc.conf, and to my surprise, was told that
>>>/etc/rc.conf wasn't writable.  Turns out it was because / was mounted
>>>read-only:
>>>
>>>...
>>>
>>>/dev/ad0s3a on / (ufs, local, read-only)
>>>devfs on /dev (devfs, local)
>>>/dev/ad0s3e on /usr (ufs, local, soft-updates)
>>>/dev/ad0s3d on /var (ufs, local, soft-updates)
>>>/dev/md0 on /tmp (ufs, local)
>>>
>>>The rc scripts helpfully mounted an MFS /tmp for me, which while
>>>friendly, succeeded in masking the problem and allowing the system to
>>>come up in a rather undesirable state (from my perspective).  So it
>>>sounds like maybe / wasn't remounted properly, and then the scripts
>>>were too helpful thinking it was a diskless system.
>>>
>>
>>I have seen this for some days,  one machine I even have to reinstall
>>the system because mount -u / does not work. :-(
> 
> I've seen reports that mount -u -w / works whereas mount -u -o rw / doesn't, 
> so you might be able to mount -u -w / in single user mode after running fsck 
> as a way to recover.  Either that or boot single user, run fsck, and then 
> reboot before going into multiuser.

this is all very nice as workaround, but does somebody actually working 
on the _real_ problem?

it would be nice to have something in UPDATING saying this is broken 
now. all i can find in UPDATING is

20051129:
  The nodev mount option was deprecated in RELENG_6 (where it
  was a no-op), and is now unsupported.  If you have nodev or dev listed
  in /etc/fstab, remove it, otherwise it will result in a mount error.

sure that is not the problem, is it?

thanks,
max