10
Cisco 3900 Series, Cisco 2900 Series, and Cisco 1900 Series Integrated Services Routers Generation 2 Software Configuration Guide
Chapter Overview of the Hardware and Software
IOS Commands
Random
Entropy
No special
Command exists
for this.
After the system
boot up, entropy is
collected by
accessing the
security chip. This
is potential
enough to flap the
BFD session
immediately after
the router boots
up.
No command Potential enough to flap bfd.
Crashing the
router on user’s
wish.
test crash This is a hidden
Cisco IOS
command to crash
the Cisco router
on a user’s wish.
Router#test crash Potential enough to flap bfd.
License EULA license accept
end user
agreement
To accept the
End-user License
Agreement
(EULA) for all
Cisco IOS
software packages
and features at one
time.
Router(config)#lice
nse accept end
user agreement
Potential enough to flap bfd.
RTC Battery
Failure
No CLI Write the event of
losing battery for
Real Time Clock.
No CLI Potential enough to flap bfd.
Note This is a one-time event during a
hardware failure.
Erasing NV
memory.
erase nvram This command
erases the nvram:
file system.
Router#erase
nvram:
Potential enough to flap bfd.
Erasing
startup-config
erase
startup-config
This command
erases startup
configurations.
Router#erase
startup-config
Potential enough to flap bfd.
Erasing NV
memory.
write erase This command
erases the NV
memory.
Router#write erase Potential enough to flap bfd.
Writing
configuration to
memory.
write This command
quickly saves
config to memory.
Router#write Potential enough to flap bfd.
Table 7 Cisco IOS Commands
Functionality Command Name Description
Configuration
Example Impact