Munir Nassar wrote:
> 
> Steve Siegfried writes:
> 
> > Actually, you don't need a static IP to run an email or http server.
> > There are dynamic DNS servers out there that let you send/receive
> > email as "sean at Waite.org" (or whatever) and host a web server at
> > your domain, too.  Google "Dynamic DNS service" (with the quotes)
> > for a list of suppliers.
> > 
> > I'm using www.tzo.com dynamic DNS service.  Been with 'em for 5+ years
> > and it works great... oh yeah... my net-tone supplier is Comcast.
> > 
> > Costs involved are:
> > 	- monthly Comcast service (you're already paying this)
> > 	- a domain name ($10-35/year)
> > 	- a DNS forwarding agent ($0-60/year)
> 
> I would urge you NOT to do it this way. while the rfcs are a bit fuzzy on 
> the issue, an SMTP server should have matching forward and reverse dns 
> entries and many anti spam features make use of this.
> 
> I've been doing it for a long time and i am starting to see major 
> ISPs and email providers(like Hotmail and AOL) do the same and reject mail 
> when forward and reverse dns does not match. There is no reason why a 
> legitimate mail server does not have matching dns entries.
> 
> Do yourself and all of us a favor and do the right thing; use a mail 
> server that has matching forward and reverse dns matching.
> 

You get around that issue by using "Smart" relay host, which for Comcast
looks like (in sendmail.cf):
	> # "Smart" relay host (may be null)
	> DSsmtp.comcast.net

Hotmail, AOL, et al have been rejecting mail when forward/reverse DNS
do not match for quite some time... like since CodeRed came out in 2001
(or was it the ILOVEYOU virus in 2000?).