Is there a way to remove/reset the history or accounting of a) a particular user, b) everyone so that their cluster ID counter starts back at 1 and the history of previous runs is removed from a condor pool.
The cluster id is per-schedd, and cannot be set per user.
If you want to reset the saved accounting history that is used for the fair-share algorithm for a particular user, an administrator can use the condor_userprio -setprio command to reset the priority, and override the historical usage.
If you want to remove the historical job information that is
displayed by the condor_history command, there is no way to do
this per-user, as all of these job ads are stored in the history
files. You could remove the history files by hand if you really
wanted to erase all job history. The base history file can by
found by running condor_config_val HISTORY
If you want to remove all active jobs for all users in the queue, and reset the clusterid back to one, you can remove the job_queue.log file in the condor spool directory. Obviously, this is a very dangerous thing to do with a production system.