On Sat, Jun 19, 1999 at 12:07:11PM +0200, Peter van der Landen wrote:
> > Also set the queue directory of the mail daemon to update
> >synchronously. The following example is for sendmail:
> >
> > /sbin/chattr +S /var/spool/mqueue
>
> Should I conclude from this that somehow Linux is extra vulnerable to queue
> corruption (there's no such instruction for other OS'es). If so, why doesn't
> Dan (who I know as a very careful person) recommend this?
>
> Is it a good idea to apply this +S attribute to the Qmail queue directory?
> Would it have a high impact on performance?
In Linux, in case of power loss you can lose the mail that you received in
the last 30 seconds.
The chattr trick was suggested a year ago on this list. I tried it but it
didn't help at all in case of directories. I guess the attribute only works
for files which are opened, not for directories where files are opened. I
have no idea if something has changed after that.
But there's a little shared library which adds extra fsync() system calls
and which should make qmail on Linux reliable:
ftp://elektroni.ee.tut.fi/pub/qmail_linux_metadata_message
(the included patch for the kernel is not needed any longer)
