Ah, but many anti-spam solutions do use PTR entries, on the theory that anybody not using a proper PTR is a) illegitimate, b) a 'dynamic' user that should be sending mail through their ISP's MTA, or c) so clueless that they're a huge security risk.
> -----Original Message----- > From: mikrotik-boun...@mail.butchevans.com [mailto:mikrotik- > boun...@mail.butchevans.com] On Behalf Of Terri Kelley > Sent: Wednesday, May 12, 2010 11:06 PM > To: Mikrotik discussions > Subject: Re: [Mikrotik] smtp delay > > Well I am not so sure. Our own email server should not require reverse > lookup for a client logging in and sending email. That is the norm for an > email server. Where PTR comes into play is when one email server sends an > email to another server. So that reverse lookup should not happen on the > initial send from a customer here to our own email server. > > PTR entries are usually only enter for servers, especially email servers > since that is a spam check. Think of a business. They don't have PTRs for > every desktop in their enterprise. That would be a nightmare. > > Terri Kelley > Network Engineer > 254-697-6710 x 1140 > Farm to Market Broadband > www.farm-market.net > > > This email message is intended only for the named recipient(s) above, and > may contain, together with any attachment(s), confidential information > that > is privileged. If you are not the intended recipient, be advised that you > have received this email in error and that any use, dissemination, > forwarding, printing, copying or distribution of this message and any > attachment(s) is strictly prohibited. > > > > > On May 12, 2010, at 1:23 PM, Butch Evans wrote: > > > On Wed, 2010-05-12 at 12:37 -0500, Terri Kelley wrote: > >> Really doubt it is my mail server. I have one customer > >> complaining that it happens to him when using other smtp > >> email servers. > > > > If you are natting, then DNS may still be the issue. If you ARE > > natting, then do a reverse lookup on the IP that you are natting to. > > I'd bet that you'll find there is no PTR record for that IP. > > > > > > -- > > ******************************************************************** > > * Butch Evans * Professional Network Consultation* > > * http://www.butchevans.com/ * Network Engineering * > > * http://store.wispgear.net/ * Wired or Wireless Networks * > > * http://blog.butchevans.com/ * ImageStream, Mikrotik and MORE! * > > ******************************************************************** > > > > _______________________________________________ > > Mikrotik mailing list > > Mikrotik@mail.butchevans.com > > http://www.butchevans.com/mailman/listinfo/mikrotik > > > > Visit http://blog.butchevans.com/ for tutorials related to Mikrotik > RouterOS > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://www.butchevans.com/pipermail/mikrotik/attachments/20100512/6360187 > f/attachment.html> > _______________________________________________ > Mikrotik mailing list > Mikrotik@mail.butchevans.com > http://www.butchevans.com/mailman/listinfo/mikrotik > > Visit http://blog.butchevans.com/ for tutorials related to Mikrotik > RouterOS _______________________________________________ Mikrotik mailing list Mikrotik@mail.butchevans.com http://www.butchevans.com/mailman/listinfo/mikrotik Visit http://blog.butchevans.com/ for tutorials related to Mikrotik RouterOS
