If you have setup a zone delegation properly for EP.petronas.com.my then you do not need to add additional delegation zones.  You can do an nslookup on NFS.EP.petronas.com.my and it will resolve.  The same with all the other SmartConnect zones.  The only feature you lose when you do this is the ability to use short names with most DNS resolvers.  Let's assume your DNS search domain is petronas.com.my  nslookup EP <--- This will work and resolve to the SIP. nslookup NFS <-- This will not work as it will actually lookup NFS.petronas.com.my nslookup NFS.EP <-- This does not work in most cases, as having a . in the name has the resolver assume it is fully qualified.  On some clients you can configure to append your search domain if the first lookup fails.  Another way to have this work, which most customers will not want to do is to add EP.petronas.com.my to the search list.  If you do this then nslookup NFS will work, assuming there is no NFS.petronas.com.my name already existing.
Hi There,  I have 1 SSIP (EPfsssip.petronas.com.my )which will service 4 smart connect zones which are :-     My question is, do I need to create a delegation for all the zones or do just for one which is  EP.petronas.com.my. iF customer were to nslookup on " NFS.EP.petronas.com.my " for example. Would it resolve?
DNS name registration