Secret Cisco IOS Commands

Here are some commands in cisco systems' Internetworking Operating System
which are hidden from users at any privilege level. Some are informative,
while others are rather commonplace. Some will even lock the router if invoked
incorrectly. This list is a subset of all hidden commands. Descriptions
of commands are included where possible. All were tested on a device running
12.0-6S.



exec commands

@clear profile (clear cpu profiling)
@debug ip ospf monitor
@debug oir (debug online insertion and removal)
@debug par mo (debug parser modes)
@debug sanity (debug buffer pool sanity)
@debug subsys (debug discrete subsystems)
@debug buffer (additional buffer debugging)
@gdb kernel
@gdb examine pid
@gdb debug pid
@if-console [] [consoledebug]
@profile .
@sh chunk (show chunks of memory allocated to processes)
@sh chunk summ (show chunk allocation summary)
@sh idb (shows interface database)
@sh in stats (gives you switching path output per interface)
@sh ip ospf maxage-list
@sh ip ospf delete-list
@sh ip ospf statistic
@sh ip ospf bad-checksum
@sh ip ospf event
@sh isis timers
@sh isis tree IS-IS link state database AVL tree
@sh isis tree level-2
@sh isis private
@sh profile [detailterse] (show cpu profiling)
@sh parser modes (shows current process access-tree.)
@sh parser unresolv (shows unresolved links in access-tree)
@sh list
@sh list none
@sh region (shows image layout)
@sh region

(shows image layout at given address)
@sh timers (show timers for timer command in config mode)
@sh int switching (shows switching path information for the interface)
@sh proc all-events (shows all process events)
@sh sum (show current stored image checksum)
@test transmit (test the transmission of L2 frames)


configuration mode commands

@boot system rom
@boot module
@exception-slave dump X.X.X.X
@exception-slave protocol tftp
@exception-slave corefile
@ip route profile
@ip slow-convergence
@ip tftp boot-interface
@loopback diag
@loopback dec (at dec chip)
@loopback test
@loopback micro-linear
@loopback motorola
@scheduler max-task-time 200 (last val in milliseconds)
@scheduler heapcheck process (memory validation.. after proc)
@scheduler heapcheck poll (memory valid after some poll)
@scheduler run-degraded (perhaps in a failure mode?)
@service internal
@service slave-coredump
@service log backtrace (provides traceback with every logging instance)
@tunnel carry-security