How to list currently connected users

Dear colleagues,

I would like to know if there is any way to display a list of connected users so I can have some information and make sure that the number of available Global consoles is never exceeded.

Besides that, do you know if there is any limit on the number of logons for each user? We are experiencing strange logon errors depending on the user chosen to access the SAM system.

Thanks in advance for your time,
Hector