> Dear all,
> I have asked the following question on
> But then it clicked to me that I should have directed
the question here on livecd list.
> Is automounting of LVM volumes by a livecd dangerous?
Probably you've heard this before, but the short answer
is 'it depends'.
If you believe in the philosophy that a default livecd boot
guaranteed to not write any bits on system disk/storage,
then yes, it is
dangerous. I'll even go one further- it's even
dangerous to mount ext3
When implementing liveusb-persistence, an early variation
implementation would attempt to readonly mount every disk,
persistent overlay files to utilize. Ultimately, for the
persistence release, I backed off of the flexibility that
doing so would
enable, and now the current fedora liveusb mechanism will
default look at the booting media (e.g. usbstick) for the
file which is by definition already mounted.
One thing I noticed in that earlier implementation was that
if you did a
'blockdev --setro' on devices before attempting to
mount them readonly
(because like me, you are ultra paranoid, and believe that
be confident that by default no bits on their disks will be
Anyway, if you do that, and then try to mount readonly an
you'll be confounded by the fact that the mount now
fails, because for
some reason mounting an ext3fs readonly is not a purely
operation. I think maybe in some instances it really wants
the journal. I vaguely recall also trying to mount an ext3
as an ext2 filesystem, but I vaguely recall that not
Ultimately, for another tool I was working on (viros.org
I ended up
implementing a devicemapper solution. I.e. to be truly
can blockdev --setro, then build up a devicemapper snapshot
to ram to
get a virtually writable device, which you can then mount
amusingly, get some visibility into which bits get written
in such a case).
But back to your question- Another very good reason to be
paranoid, is whether or not you want to support the
- user has ubuntu(or any distro) installed on their system
- user hibernates
- user boots your livecd
- user reboots, and wants to unhibernate
- user is hosed if you mounted filesystems that were
mounted in the
By default slax mounts all devices rw including NTFS partitions. Maybe a warning should
be placed on the use. Anyhow, I have not seen it be dangerous with regular partitions.
Thank you for your input, I will relay the information to Tomas.