To further elaborate on what Ken said- By default a client that knows in what AD site it is in, will ask for a DC in that same site by querying DNS with:
* _ldap._tcp.<SITE>._sites.dc._msdcs.<DOMAIN>.<TLD> By default all DCs in AD site <SITE> will register that DNS SRV record. If no DCs are in that AD Site, the DCs in the nearest AD site will cover that AD site by registering their records in the DC-less AD site. The DCs in the site list are in a random order and provided by the DNS round robin mechanism. If a client does not know in what site it is in, it will ask for a DC in that same domain by querying DNS with: * _ldap._tcp.dc._msdcs. <DOMAIN>.<TLD> ________________________________ From: Ken Schaefer [mailto:[EMAIL PROTECTED] Sent: Wednesday, March 05, 2008 3:21 PM To: NT System Admin Issues Subject: RE: Default DC? -Client retrieves list of DCs from DNS -Client pings all DCs -Whichever responds first, client attempts to authenticate to -If the DC sees that there is a more appropriate DC based on site link costings, then the DC will return a referral to the client Cheers Ken From: Roger Wright [mailto:[EMAIL PROTECTED] Sent: Thursday, 6 March 2008 2:39 AM To: NT System Admin Issues Subject: Default DC? What determines which DC a user connects to when logging in? I've got one DC in a remote location yet some of my local machines are authenticating against it rather than the ones in the local network. Roger Wright Network Administrator 727.572.7076 x388 ~ Upgrade to Next Generation Antispam/Antivirus with Ninja! ~ ~ <http://www.sunbelt-software.com/SunbeltMessagingNinja.cfm> ~
