[CentOS] centos] Useful NFS hint

[Gordon Messmer]

On 05/17/2010 03:44 PM, Ray Van Dolson wrote:
> What about re-mounting the same block device (presumably as ext3) in ro
> mode at another mountpoint?
>
> Or if that complained, maybe created an additional block device under
> /dev with identical major/minor numbers and mounting *that* RO?
>
> Maybe ext3 wouldn't handle that too well...

I'm reasonably certain that in the former case "mount" will refuse to 
mount the device twice, and in the latter case the kernel will report 
that the filesystem was not unmounted properly and refuse to mount the 
FS until it has been.

Even if mount and the kernel allowed you to do this, at some point the 
kernel could potentially read inconsistent data from the device and 
crash.  You'd never want to do this.