Directory Access tab in ESM/Servername when configured to auto

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I was under the impression that when you configure the Directory
Access tab in ESM/Servername to auto, it would first look for a GC it
its own site, then look out of its own site for a GC.

I have two sites, one local for the LAN here and one for a remote
datacentre that holds two machines, one 2003 DC/GC and one 2003
Exchange2003 Standard.

When my remote DC/GC was rebooted I noticed the Exchange was
reporting that it could contact the DC/GC in the other site either,
despite the fact it could ping the machine by IP/NetBios/DNS name -
what could be causing this?

Any ideas?

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