On Wed, 12 Jul 2000, Dmitry Alyabyev wrote:
> Why ? What is wrong in the MX-list ?
What is the point of having the same host at different priorities?
> >> 123.com preference = 30, mail exchanger = relay2.mydomain.com
> >> 123.com preference = 20, mail exchanger = mail.123.com
> >> 123.com preference = 10, mail exchanger = mail.123.com
> >> 123.com preference = 20, mail exchanger = relay.mydomain.com
If you take this list at face value, it says
"Try mail.123.com; if that is down, try mail.123.com and
relay.mydomain.com in either order; if they are both down, try
relay2.mydomain.com."
That is silly. Why try mail.123.com twice?
> IFAIK that is normal behavior when you put one host several times with
> different preference and have several hosts with the same pref. as
> well.
No, that is not normal practice. One host usually appears only once.
> I must to say what I've never seen a problem like this with Sendmail.
It should not be a problem with Exim. Exim just optimizes by skipping
the higher preference, because it has already tried that host.
> I understand what if first (lowest) relay is down Exim will try to
> connect to anothers (with pref. 20) but it's extremely wrong to treat
> itself like "lowest MX record" in the case.
Please understand: I do not think this is the cause of your problem. I
just pointed it out as something that was unusual. Of course, it
*might* be the cause - it is a rare situation, so the code in Exim is
not often tested, and any code may contain bugs. If it really is the
cause, then Exim needs to be fixed, but as I said, I don't think it is
very likely to be.
However, when I get time I will set up a test like this just to make
sure Exim is working as it should be.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
