As per your other thread you just need to use the Cisco config guides. Here is the one for the 3900 router -
See the thread in firewalling for the ASA. As for CPU see the thread in firewalling as well.
Hmmm, it should be, perhaps there is a problem with your browser ?
Anyway, on the Cisco homepage search for "12.4T network management configuration". Click on the link in the results page for the above and then go to chapter 3 "Troubleshooting, Fault Management and Logging". The instructions are in there.