[LINK] RFI: Email Download Failure from Local ISP

[Scott Howard]

On 1/22/08, Roger Clarke <Roger.Clarke at xamax.com.au> wrote:
>
> At 22:00+11 Tue 22 Jan 2008 and up to 23:00ish, fetches of mail from
> mail.apex.net.au were dropping out - Eudora said 'No response after
> 120 seconds'.
>
> The Squirrelmail/webmail alternative also wasn't working, just
> hanging, and finally displaying a message I haven't seen before (at
> the very bottom).



Sounds like either the POP server is broken, or you're got a massively large
mailbox which is taking too long for the server to open.  The former is more
likely...


> A search of the DNS on mail.apex.net.au delivered:
> 15 - postoffice.telstra.net.au. (203.50.2.186)

[Only one MX record??  What kind of fallback arrangements are in place??]


I'm not sure where you're getting this result from.
MX records are for domains, so you should be looking at the MX record for
apex.net.au, not mail.apex.net.au.  This gives :
apex.net.au     mail exchanger = 15 postoffice.telstra.net.au.
apex.net.au     mail exchanger = 0 mail.apex.net.au.
apex.net.au     mail exchanger = 10 mail2.apex.net.au.

So their own mail servers are the primaries, and Telstra is a backup (lowest
numbers are highest priority, the order they are listed in above isn't
relevant)

mail.apex.net.au doesn't have any MX records, nor seem to have anything to
do with telstra, so I'm not sure where the results you got above came from.

[I've previously threatened to abandon them because the backup
> DNS-server is on the same subnet as the primary, in breach of the
> (advisory only) IETF RFC, i.e. the nearest thing to a standard that
> exists in Internet contexts]


Given that their entire ISP is probably on that same subnet,  it probably
doesn't make a lot of difference.  There are a hell of a lot of "advisory"
RFCs out there - many of which were far more relevant in a 1990's Internet
rather than a 2008 Internet (Not to mention that many of them contract
either themselves, other advisory RFCs, or in many cases contract the
standards track RFCs...)

An attempt to fetch mail from mail2.apex.net.au produces:
> Server not responding. 706; Lost connection to the server.



Not unexpected - you're trying to connect to it using POP or IMAP, when
there's nothing to say that this server actually supports either.  Having it
listed as an MX record means that it's willing to _accept_ mail on port 25,
not that it's a valid host for you "fetching" mail from it.  That said,
mail2.apex.net.au is also refusing connections on port 25, so...

$ telnet mail2.apex.net.au 25
Trying 203.20.62.11...
telnet: Unable to connect to remote host: Connection refused

  Scott.