AB Client Sessions perfmon counter...

[Guest]

Trying to locate/find some additional info on this counter. What does this
counter directly indicate? Is this counter indicative of the number of
outlook clients connected to the DC? Which other app/process can show up as a
session under this counter, on a domain controller? Any info/insights will be
much appreciated!

 

[Joe Richards [MVP]]

The official definition is

Shows the number of connected Address Book client sessions.

This would be any client applications that know how to create an address book
session to the global catalog through NSPI. If you are trying to find what
clients are touching the AB, you would have to query the endpoint mapper for the
NSPI port and then start filtering network traffic with a sniffer and pulling
off any traffic to/from that port and work out the IP addresses from it. As to
which app on a given machine is generating it, that will be tougher but you
might be able to find out via any tool that maps ports to processes.