subdomain points a different NS
 

Hi,
Sorry, if this is not the correct forum to post DNS issues.
(i'm new to LQ.org)

This is my problem

I have a domain, assume.. mydomain.com. currently it is hosted in "ISPA" (assume), they provide me the freedom to edit my Zone file. (mydomain.com.db)

Now, I want to host one of my subdomain in "ISPB" (on a different isp, while the main domain remain hosted on "ISPA"),

assuming the sub domain is "subd.mydomain.com", and the "ISPB's" NSs are "NS1.ISPB.COM" and "NS2.ISPA.COM".

What are the records to be added in my main domain zone file.?

thanks
Viraj