Send a DNS query specifying one of the criteria specific DNS host names
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Yes
Among all DCs returned by the DNS server, that has not been pinged yet, choose one DC based on weighted random order. Ping it. Wait for 0.1 sec and listen for responses from this and previously pinged DCs.
NoNo
Did you receive a
DC's response?
Yes
Does it match
client's
requirements?
Yes
Cache the the
result and return it to client
Finish
Discovering Site specific DCs
When a locator searches for a DC, it attempts to find one in the same site where the client is unless specified otherwise. If at the beginning of the search the locator is not aware of the client’s site, it will query a DNS server for the records of the DCs in the specified domain. Then it contacts discovered DCs and finds the site to which the client belongs. If the discovered DC is not in the same site the locator will repeat DNS query specifying the client’s site.
Windows 2000 White Paper
35
