Re: e-postage stamps, was Welcome to the new(ish) ASRG list

On 3/17/2013 1:09 AM, Franck Martin wrote:
> I'm all for outright blocking on no rDNS but who are these large ISPs?

I don't have a list off the top of my head... but I did have a friend
who is an IT guy at a company and where the made some changes to their
firewall just two weeks ago... which mistakenly caused their exchange
server's outbound IP to switch to an IP that didn't have rDNS.
Immediately, there were massive numbers of outbound messages blocked
across many recipients, including some large ISPs. I didn't make a list,
but he said, "we're being blocked by this and that"... and I recall
hearing some "household names". (Also, this wasn't totally scientific
since you could argue that their IP being "new" might have factored into
the mix... but they were NOT sending ANY spam at that time!)

Also, I recall a person high up at Cox Communications saying that they
block on "no rDNS", fwiw.

-- 
Rob McEwen
http://dnsbl.invaluement.com/
[email protected]
+1 (478) 475-9032