notes

Cisco Shortcuts

General

  1. ? shows the list of available options (like tab in linux)
  2. do <command> - run admin commands from global config
  3. show running-config show the current configs
  4. w - save configs
  5. no ip domain-lookup - disable ip domain lookup

Auth

  1. Enable sync console (to avoid bad user expirience during typing)

     conf t
 line console 0
 logging syncronous

  2. Configure enable mode password

     conf t
 # the old way to do it is `enable password <password>`, but with password command it is not encrypted
 enable secret <password>

  3. Create user with password

     conf t
 username max secret <password>

  4. Secure console access

    conf t
line console 0

# use global password
login
password <password>

# use local user/password database
login local

  5. Configure telnet access

     cont t
 line vty 0 4

 # use global password
 login
 password <password>

 # use local user/password database
 login local

 transport input all

  6. Configure ssh access

     cont t

 crypto key generate rsa general-keys modulus 2048
 ip ssh version 2

 line vty 0 4
 login local
 transport input ssh

Switching

  1. show ip interface brief - show int info from global path

VLAN config

Switch

  1. View VLANs

     show vlan
 show interface f0/1 switchport
 show interface trunk

  2. Create VLAN

     conf t
 vlan 10
 name "vlan-name"

  3. Add interface to VLAN

     cont t
 int f0/0

 switchport mode access
 switchport access vlan 10

  4. Set interace as a trunk

     int f0/1

 # required for old switches, default value for new
 switchport trunk encapsulation dot1q

 switchport mode trunk

 # disable Dynamic Trunk Protocol (DTP)
 switchport nonegotiate

Router on a Stick

```
conf t

# create subinterface 10
int f0/0.10

# set VLAN 10 for this interface
encapsulation dot1Q 10

# set IP address for a new interface
ip address 10.0.0.1 255.255.255.0
```

Routing

Static Configs

  1. show ip route - show the list of routes

  2. Set IP address

     conf t
 int f0/0
 no shutdown
 ip address 10.0.0.1 255.255.255.0

  3. Create loopback address

     conf t
 int loopback 1
 ip address 10.0.0.1 255.255.255.0

  4. Set default route

     ip route 0.0.0.0 0.0.0.0 g0/0 10.1.0.99

OSPF

  1. View OSPF data

     show ip protocols
 show ip ospf
 show ip ospf interface brief
 show ip ospf neighbour

  2. Enable OSPF

     route ospf <process-id>

 # advertise any network with 10.x.x.x
 network 10.0.0.0 0.255.255.255 area 0

 # advertise any network
 network 0.0.0.0 255.255.255.255 area 0

 # set base for cost calculation to 1Gb/s
 auto-cost reference-bandwidth 1000

 # advertize default role
 network-information originate

Hints

  1. Configure the list of interfaces

     int range f0/1-24