dns resolution delays

[Kevin Darcy]

I'm surprised you can get any resolution at all: I can't, even when
querying both delegated nameservers directly with a 2-minute timeout
setting...


- Kevin

Eric wrote:

> We have an internal dns that resolves internal names.  Anything
> external like microsoft.com will be forwarded to external name
> servers.  For some reason, when I do an nslookup -type=mx itsa.com
> which should return an invalid address, it takes 1 minute 15 seconds
> to return " can't find itsa.com: Non-existent host/domain".  I run it
> again and it takes 20 seconds.  I run it again and it takes 1 minute
> 15 seconds again.  It seems to be totally random as to which time span
> it takes.  What I'm thinking is that there is some sort of random
> picking of which nameserver to forward the request to on the immediate
> nameserver.  Whichever nameserver it auto forwards to designates how
> long the request takes.  I also believe that since 1 of these servers
> is very slow and the other very fast, that the one that is slow has an
> issue.  Is there any way for me to do like a traceroute of this dns
> request so I can see exactly where the request is being forwarded and
> from which server it is awaiting a reply?