I have a test network with 3 DC's all running DNS. 2 DC's are on the test.local domain. 1 DC is on a sub domain named subdomain.test.local. On the name servers tab of the test.local domain, it lists the name server for the sub domain, as well as the expected 2 DC's from the test.local domain. Is this normal? Should the sub domain's name server entry be deleted?