Hello Cisco_lite,

debug commands can have such a disruptive effect on the network device even on a powerful one like a C6500 with Sup720.

For example by using a debug stp I caused a C4500 to become unusable and I needed someone to reload it !

Actually, displaying in a console has a great impact on the system you should

increase the local logging buffer size to 1000000 bytes or more

logging buffered

logging console 4

set logging console 4 to avoid to see debug messages on the fly then later you see the logging buffer by using

sh log

Think that usually is less heavy to export log messages to a syslog server then to have them displayed on the console or VTY connection.

We used this method of exporting to a syslog with logging disabled on the console, to get some debug outputs for Cisco TAC during some Service Request.

Hope to help

Giuseppe