It's okay that there are history files logging the commands that has been used. That't not the problem. The problem is that when 2 admins are logged in to an AIX server then it could be bad:
If admin #A uses
rm FILENAME
then if admin #B hits the up arrow he gets the
rm FILENAME
command which is not a very good thing. So how can the termial be forced to only write the command history if the ssh session ended? (UPDATE#2: or solution could be that that each session has it's uniq command history, and thus we can't see each others command, only when they sign out for ex.)
UPDATE#1
4:root@SERVER:/root # echo $SHELL
/usr/bin/ksh
4:root@SERVER:/root # oslevel -s
6100-05-01-1016
4:root@SERVER:/root #
bash
feature other shells can behave differently.