how to block a user temporarily?

hi to all

i'm a newbie on aix.

how would i block temporarily a few users in accessing our aix server so that other users may not be affected by th cpu usage...because if all of them accessing our server the CPU utilization goes high...

thanks

winky

Set their shells to a program that simply exits

Not sure about AIX but try:

echo "System busy... Please try again later." > /etc/nologin

lock their user account so they cannot login:

chuser account_locked=true <user_name>