Mount same ext3 filesystem in 2 places... at the same time

[Anton Verevkin]

William, I would not be that sure about that. I've just tried such double-mount on my Debian system and it has
mounted silently, with not even a single warning message.

What I am trying to say is when both mounts happen in the same operating system/kernel, the developpers
have all they need to forsee such situation and correctly manage both of them together. However I am not
100% sure they did. Please someone correct me if you know the details of FS-stuff in Linux kernel.

Really bad things happen when a filesystem is mounted from two computers at a time (with SCSI bus, Fibre
Channel or other methods that allow access to the same physical disk from several machines). In this case
computers can not even guess that thay are not exclusive users of this filesystem and can corrupt it if both 
mounts are read-write.

Anyway I would always suggest mounting filesystems only once as the best practice. If you later need its 
contents mirrored in another place you can always use mount with 'bind' option (or 'rbind' if you need access
to mounted subdirectories). It is way more safe and flexible.

Best regards, 
Anton Verevkin 

On Tue 29/09/09 12:00 , William Muriithi <william.muriithi-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org> wrote:
> John
> >
> > Still being a #NIX newbie, thought I ought to pose the question:
> >
> > Can an ext3 filesystem be mounted in 2 places at the same time?
> >
> No, unless you want data corruption.
> Only cluster aware file system like gfs can safely be mounted in
> multiple points
> > Thanks!
> >
> > JohnM
> >
> >
> --
> The Toronto Linux Users Group.      Meetings: http://gtalug.org/
> TLUG requests: Linux topics, No HTML, wrap text below 80 columns
> How to UNSUBSCRIBE: http://gtalug.org/wiki/Mailing_lists
> 
> 
--
The Toronto Linux Users Group.      Meetings: http://gtalug.org/
TLUG requests: Linux topics, No HTML, wrap text below 80 columns
How to UNSUBSCRIBE: http://gtalug.org/wiki/Mailing_lists