Author: John W. Baxter Date: To: exim users Subject: Re: [exim] SMTP processing hangs during bayes sync
On 8/31/06 10:02 AM, "W B Hacker" <wbh@???> wrote:
> We do have to 'brownlist', for example, NetSol, who send from IP's with no DNS
> entry, but even there, it is only for traffic from one domain.tld, and fewer
> than a dozen usernames we allow in that domain.tld. The rest can whistle.
Our little nonameok.txt file (which prevents generation of the headers we
create that SpamAssassin gives points for) presently has 51 lines. It
probably doesn't have that many *needed* entries, as I add entries as needed
but haven't recently done a pass through it to remove IPs that now DO have
reverse name service.
Just today, my message from the Washington State Lottery mailing list wound
up in my Spam folder because of the points added for no name: the state
outsourced (or changed the outsourcing) of the list to a company whose mail
server has no reverse DNS (really none, as opposed to reverse that doesn't
please Exim). So nonameok.txt grew by one entry today.
We learned early on (which for us means mid-1990s) that we couldn't afford
to simply block for no name: The state runs DNS for all the school
districts in the state except Seattle, and didn't know how to do it right
(and still messes it up now and then, although they seem now to *intend* to
have it right). Teachers really don't like it if they can't send email from
school to spouses at home--and no one at the schools involved can fix the
problem.
We spent a LOT of support time trying to educate admins about DNS in the mid
to late 1990s, and gave up (we couldn't afford to continue).