Re: unknown rDNS

Sorry guys, today, your two answers were classified as Virus/Spam 
(unofficial) and I had to fetch them from quarantine :)

A virus was found: SecuriteInfo.com.Spam-111760.UNOFFICIAL
Scanner detecting a virus: ClamAV-clamd

The reason was mentioning the PTR of 107.150.1.216 in the mail. This is 
a well-known hosting provider whose infrastructure was frequently used 
to operate spam servers.

 From: Reindl Harald
> because "suomenporakaivo.fi" != "107-150-1-216-host.<...>"
> because "suomenporakaivo.fi" != "107.150.1.216"

In most of spam I get ehlo and rDNS are different. Absolute equality 
with rDNS is not required. In SMTP (RFC 5321), the client must specify a 
name or IP literal in HELO/EHLO that identifies it. rDNS itself is 
useful for reputation checks, but there is no requirement that EHLO == 
rDNS.

 From: Matus UHLAR
> while the IP has PTR record, the name in PTR does not exist, so nobody 
> will
> seriously use its content.

Didnt know that it also checks the name in PTR. I put this info into my 
docu as a reminder.

Best regards,
Thomas B