how to find out who's propagating wrong IP for my server?

[Simon Waters]

Mark Lin wrote:
> 
> We recently switch ISP, so we change our DNS entry too.  Here's the
> funny thing,
> my company website is www.macysnyc.com and when you ping that name, it
> will return 209.10.179.184 which is also my primary domain name
> server(baldur.macysnyc.com, btw that's the correct IP).  But if I just
> ping baldur.macysnyc.com, it will "SOMETIMES" return me with
> 64.63.59.41 which is IP I used to have from the old ISP.  So my
> question is, how can I find out for sure who is still propagating old
> IP address of my server for me?

Looks like it is the gtld-servers.net - the servers that run
"com".

So presumably you have some other domains registers for which
this server is the DNS server, and this still points to the old
address.