dual-ported raid

[Jeff Garlough]

Hi,

I have a dual-ported raid controller which allows two computers to
connect to the same ext3 filesystem. I never mount both systems
read-write at the same time. What I would like to do is use one
normally, and mount the second system read-only to perform backups and
to rsync the filesystem to another filesystem. When it's mounted
read-write from another system, will mounting the same filesystem
read-only cause the journal to be committed at the time it's mounted? If
so, is that a bad thing, that is, will it corrupt the filesystem? Are
journal events handled similar to databases, with regard to transaction
processing of journal events, or could playing "partial" journal events
(if there is such a thing) cause corruption?  Is mounting the read-only
instance as a ext2 filesystem the best solution, or does it matter if
it's mounted ext2 or ext3 as long as it's read-only?

--
Jeff Garlough