[ILUG] sendmail

[Declan Grady]

Yeah.. that makes sense about the caching, I guess.

I had a look at the logs with a 'cat messages | grep pppd | grep Connect'
and it is mostly 5 minute connection times.. very rarely connecting for more
than 15 mins.
(Well, it *is* a 56k modem !)

Thanks for all the replies.

fyi, I do indeed have a fixed IP addy, but then again I do pay IOL through
the nose for it.

Cheers,
Declan



> -----Original Message-----
> From: ilug-admin at linux.ie [mailto:ilug-admin at linux.ie]On Behalf Of Niall
> O Broin
> Sent: 20 June 2002 17:49
> To: Ilug at Linux.Ie
> Subject: Re: [ILUG] sendmail
>
>
> On Thu, Jun 20, 2002 at 05:10:11PM +0100, Declan Grady wrote:
>
> > When I dialup to iol I get a fixed ip addy.
> > Iol's relay(s) then dump my mail to my sendmail to handle.. no problems
> > there.
> >
> > However, I would expect to receive mail direct to my box form
> other sources,
> > but I dont seem to. Everything comes from relay1.mail.iol.net or
> > relay2.mail.iol.net.
> >
> > I do have some ipchains rules, but I dont see anything obvious in the
> > syslogs to show denied connection attempts.
> >
> > If I do a 'dig mx nuvotem.com' my fixed IP is listed with the highest
> > priority, so I would expect to be receiving mails while I'm connected.
> >
> > Am I missing something ?
>
> Probably :-)
>
> I'm guessing that relatively speaking, your fixed IP is more
> often than not
> unreachable. So mostly sending mail servers will fail to reach
> it, and will
> use instead one of the backup MX and (now comes the guessing
> part) they will
> cache this for a period of time (the guessing here is becuase I don't know
> how caching of MX to A rec. is done, or if it's done at all. The cricket
> book is silent about it, but domain data is cached -> MX records
> are cached.
> However, is the fact that we had to use a particular MX last time
> cached, or
> is a fresh lookup done each time - I don't know.
>
> But if that result is cached, it would go a long way to explaining your
> problem.
>
>
>
>
> Niall
>