Mail log problem -

[David G. Miller]

Bob Goodwin - W2BOD wrote:

> "reverse DNS?"  Wireshark displayed a number of lines about DNS which 
> > I did not understand.  I hate to admit it but what's a reverse DNS?  
> > Guess I need to look that up ...
> >
> > Bob Goodwin
> >
>   
> Ok, I see reverse DNS is simply reversing the process, not sure how that 
> affects me?
>
> The maillog does show some cryptic [to me] errors:
>
> Jun 28 16:36:55 box6 sendmail[1091]: l5SKaLF4001091: 
> to=bobgoodwin at wildblue.net, ctladdr=root (0/0), delay=00:00:34, 
> xdelay=00:00:30, mailer=relay, pri=989592, relay=[127.0.0.1] 
> [127.0.0.1], dsn=5.6.0, stat=Data format error
> Jun 28 16:36:55 box6 sendmail[1091]: l5SKaLF4001091: l5SKaLF5001091: 
> DSN: Data format error
>
> Perhaps someone can tell me what this means?
>
> Maybe I should just wait until I've installed Fedora 7.  It may be 
> different then.
I just did a Google search for "DSN: Data format error" and got a bunch 
of hits.  It could be that your ISP wants a valid host name or at least 
domain name (resolvable through DNS) before accepting mail.  You may 
need to set up something through one of the dynamic DNS services so your 
stuff can be resolved.  Alternatively, you may be able to set up 
Wildblue's mail server as a "smarthost" in your sendmail configuration 
(Google for "smarthost sendmail", I haven't set it up for a while so 
you'll do better with Google than relying on my memory).

A lot of the spam on the 'net is sent through zombies that typically 
don't have a valid host name/domain name or resolvable address.  It 
could be that Wildblue has decided to tighten up their requirements for 
processing e-mail even from their own subscribers.  Hopefully, they 
haven't blocked port 25 connections to customers and assume you must use 
their e-mail servers.

Cheers,
Dave

-- 
Politics, n. Strife of interests masquerading as a contest of principles.
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