What is the difference between “Exchange Legacy Distinguished Name Value” and “Distushed Name Active Directory”?

Question

I am a little confused by these two terms: " Legacy Distinguished Name " (Legacy DN) and " Distingushed Name " (DN).

The first term, Legacy DN, appears only for Exchange, and the last DN is only mentioned for Active Directory.

They are clearly not in the same format:

DN: CN = Morgan Cheng, OU = SomeOrg, DC = SomeCom, DC = com

LegacyDN is similar: / o = SomeDomain / ou = SomeGroup / cn = Recipients / cn = Morgan Cheng

I still do not quite understand what the difference is. Are these two completely different materials? or exactly the same information presented in two different forms?

And why is it called " Legacy "? If this is a legacy, something must be new, right?

Hope some experts from AD and Exchang can give me some inputs.

Answer 1

In Exchange 5.5, Exchange assigned distinguished names for accounts and mailboxes (Obj-Dist-Name). When Active Directory arrives, Exchange 2000 and later will use their distinguished names. To maintain backward compatibility, the transition from Exchange 5.5 to Exchange 2000 was moved over the old DNs to the legacyExchangeDN ActiveDirectory attribute.

Some applications continue to reference Obj-Dist-Name. To maintain compatibility with these applications, later versions of the exchange synthesize the legacyExchangeDN value even for objects that were not migrated from Exchange 5.5. RUS automatically sets it to some value, apparently with the same value as the outstandingName in your case.

The "new" way (since 2000) is to refer to objects using the distinguished name, and not to Obj-Dist-Name.