Two atwo articles on the subject of Session Broker Load Balancing are definitely worth reading. In fact, this is the best reference so far that provides some insight into the inner workings of Session Broker Load Balancing. I already knew this by poking around but it's always nice to have Microsoft itself confirm this kind of stuff. Some highlights:

• The Session Broker stores session state information in a Jet database: %systemroot%\system32\tssesdir\tsesdir.edb
• Session Broker Load Balancing has built-in black hole protection (logon throttling) and a max-session count.
• The HKLM\System\CurrentControlsSet\Control\Terminal Server\UserSessionLimit value in the registry controls the maximum number of sessions you want to allow to a Terminal Server.
• Session Broker Logging: HKLM\System\CurrentControlSet\Services\Tssdis\Parameters\TraceOutputMode
  • 0: No Output
  • 1: Output to Debugger
  • 2: Output to command window.  This option only applies when starting TSSDIS.EXE using the -debug switch for debugging
  • 3: Output to log file.  When the value is set to 3, the Session Broker log file, tssdis.log is created