2. Commands
What can be done in user mode…
Show version – displays info on the IOS &
ROM versions, uptime, image file name, &
hardware specs.
Enable
Show running-config
3. Global configuration
(configure terminal)
Change the configuration register
Config-register 0x2100
Last digit is the boot mode
View what is in flash – show flash
Add boot system commands
0 – ROM Monitor
1 – RXBoot mode
2 – look in NVRAM for commands & load IOS from flash
Boot system flash cisco-g-1.2315-9
Show ip route
4. CDP (Cisco Discovery
Protocol)
Cdp enable – starts CDP
No cdp enable – stops CDP
Cdp timer 60 – sends updates every 60
seconds
Cdp holdime 100 – keeps cdp info in ram
for 100 seconds
5. Line status
Serial 0 is down, line protocol is down
First is layer 1, second is layer 2
6. ICMP codes
! – successful
. – request timed out
U – destination unreachable
& - TTL exceeded
Trace uses the TTL to track the route
8. Static NAT commands
Configure terminal
Interface Ethernet 0
Interface Serial 0
ip address 10.1.1.3 255.255.255.0
Ip nat inside
Ip address 200.1.1.251 255.255.255.0
Ip nat outside
Ip nat inside source static 10.1.1.2 200.1.1.2
Ip nat inside source static 10.1.1.1 200.1.1.1
9. Dynamic NAT commands
<uses prior commands minus the inside
source static lines>
Access list 1 permit 10.1.1.2
Access list 1 permit 10.1.1.1
Ip nat pool Test 200.1.1.1 200.1.1.2
netmask 255.255.255.252
Ip nat inside source list 1 pool Test
10. Dynamic NAT with Overload
commands
<uses prior static commands minus the
inside source static lines & access list
from dynamic>
Ip nat inside source list 1 interface Serial
0 overload
11. NAT commands
Clear ip nat translation – used in
dynamic to reset all translations
Show ip nat translations – show which
internal addresses & ports are mapped
to which external addresses & ports
Debug ip nat – shows each time an
address is translated