On 25/06/2010, at 10:03 PM, Jay Daley wrote:
I've tried contacting AirNZ about this to no avail
so the rest of you might appreciate knowing:
For ages now I've not been able to send email via one particular email provider from
the Koru lounge in Wgtn and I finally bothered to find out why. It seems the IP address
18.104.22.168 of koruout.airnz.co.nz has been added to XBL by Spamhaus and one of my email
providers uses that to reject connections.
It probably got blocked because an infected PC connected to the Koru wireless network and
sent out spam to a Spamhaus trap, which of course sees the IP address of the NAT/proxy and
so blocks that.
It gets worse for AirNZ because the WHOIS record for this IP address gives a non-existent
email address in the notify field and so any notification from Spamhaus that they have
been blocked will have bounced.
Of course, you should probably not be using port 25 for submission, or if your mail
provider has RBLs running on their submission port then something isn't quite right.
Also, surely RBLs should be consulted to decide whether to accept mail from an
unauthenticated client, as opposed to you, who is presumably an authenticated client.
Not saying that AirNZ are doing it right, just saying that your mail provider could likely
be doing it better :-)
Though, to be honest, I'd be surprised if a more or less public connection like that
isn't listed in the XBL, given the number of random hosts that must come through it
spewing out garbage. Being able to rely on your end-user Internet connection not being in
a popular RBL is a thing of the past I think.