[NTLUG:Discuss] Sendmail slow to respond

[Patrick R. Michaud]

On Thu, May 12, 2005 at 01:58:00PM -0500, Neil Aggarwal wrote:
> Jay:
> 
> I tried several digs from the machine and several nslookups from
> my laptop.  They all come back quickly and just fine.

Are you testing forward resolution or reverse resolution?

Sendmail isn't trying to find the IP address of the host from its
DNS name (i.e., forward resolution) -- it's trying to find out the
name of the connecting host from its IP address (reverse resolution).
This makes it sound like there are some reverse-IP addresses missing
somewhere.

In other words, if you're connecting from "somewhere.com" at IP
address 24.1.26.250, you need to be seeing how long it takes to 
resolve 24.1.26.250, not "somewhere.com".

Pm