ext3 is unsafe for maildir, and with softupdates, so is ffs. One step forwards, two steps back. Fortunately, some people still have a choice. Wietse adi: > On Mon, Feb 04, 2002 at 10:34:02PM +0000, Stephen C. Tweedie wrote: > > On Mon, Feb 04, 2002 at 05:34:52PM +0800, Yusuf Goolamabbas wrote: > > > Postfix <http://www.postfix.org> does a chattr +S on its spool directory > > > when it is installed on Linux. > > > > > > Is this still required on ext3 ? > > > > I'm not sure --- it depends on what Postfix's assumptions are. If it > > expects all directory operations to be synchronous then the flag is > > still needed. If it is satisfied with fsync flushing dir information, > > then no it is not needed. > > I don't say that I know postfix better. Beside for calling fsync() > to ensure that message safely stored on the disk, postfix also > use rename(2) to move message accross queue dirs. It's okay because > postfix's queue-id use inode as it's name. > > If I understand correctly, link(2) and unlink(2) implementation > on ext3fs will be done asynchronously. This is use by postfix > (unlink()) to remove messages that already delivered (by calling > remove()). > > So, in case of power outage for example, no message will get lost, > but possibly be delivered twice. Note that postfix also mark all > of recipients which are already delivered as done (but without calling > fsync()). > > Then *I think* it's save to get rid chattr +S on ext3fs. > > On other issue, postfix also support local delivery using maildir > format (http://cr.yp.to/proto/maildir.html) which is use link(2) > and unlink(2). If there is power outage, it is possible that > linking file from tmp to new get failed. This is the same with > losing message as there is no MUA or other mail retreival agent > use that files which still stay on tmp directory. > > Regards, > > P.Y. Adi Prasaja > > - > To unsubscribe, send mail to majordomo@postfix.org with content > (not subject): unsubscribe postfix-users > >
