In this blog we will go through the procedure of configuring static routing on Cisco devices in GNS3.

Prequires

  1. Install GNS3
  2. Import Cisco device image as EtherSwitch and Router. I’m using C3660.

Example 1

Topology

   fa1/1┌────┐ fa1/2   
  ┌─────┤ R1 ├──────┐  
  │     └────┘      │  
  │e0               │  
┌─┴──┐           ┌──┴─┐
│VPC1│           │VPC2│
└────┘           └────┘

Topology of Example 1

Step by Step

on Router:

enable
conf ter
do show interfaces status
interface fa 1/1
no switchport
ip address 192.168.1.254 255.255.255.0
exit
interface fa 1/2
no switchport
ip address 192.168.2.254 255.255.255.0
exit
ip routing
ip route 192.168.1.0 255.255.255.0 FastEthernet1/1
ip route 192.168.2.0 255.255.255.0 FastEthernet1/2
end

on VPC1

ip 192.168.1.1 255.255.255.0 192.168.1.254
show ip

on VPC2

ip 192.168.2.1 255.255.255.0 192.168.2.254
show ip
ping 192.168.1.1

Example 2

Topology

   ┌───┐                ┌───┐   
   │PC1│                │PC2│   
   └─┬─┘                └─┬─┘   
     │                    │     
10.1.3.0/24          10.1.2.0/24
fa1/0│                    │fa1/2
  ┌──┴───┐fa1/15       ┌──┴───┐ 
  │Route1├─10.1.1.0/24─┤Route2│ 
  └──────┘       fa1/15└──┬───┘ 
                          │fa1/3
                     10.1.4.0/24
                          │     
                        ┌─┴─┐   
                        │PC3│   
                        └───┘

Topology of Example 2

Step by Step

on Router1:

enable
conf ter
do show interfaces status
interface fa 1/0
no switchport
ip address 10.1.3.254 255.255.255.0
exit
interface fa 1/15
no switchport
ip address 10.1.1.1 255.255.255.0
exit
ip routing
ip route 10.1.3.0 255.255.255.0 FastEthernet1/0
ip route 10.1.1.0 255.255.255.0 FastEthernet1/15
ip route 10.1.2.0 255.255.255.0 FastEthernet1/15
ip route 10.1.4.0 255.255.255.0 FastEthernet1/15
end

on Router2:

enable
conf ter
do show interfaces status
interface fa 1/2
no switchport
ip address 10.1.2.254 255.255.255.0
exit
interface fa 1/3
no switchport
ip address 10.1.4.254 255.255.255.0
exit
interface fa 1/15
no switchport
ip address 10.1.1.2 255.255.255.0
exit
ip routing
ip route 10.1.2.0 255.255.255.0 FastEthernet1/2
ip route 10.1.4.0 255.255.255.0 FastEthernet1/3
ip route 10.1.1.0 255.255.255.0 FastEthernet1/15
ip route 10.1.3.0 255.255.255.0 FastEthernet1/15
end

on VPC1

ip 10.1.3.1 255.255.255.0 10.1.3.254

on VPC2

ip 10.1.2.1 255.255.255.0 10.1.2.254

on VPC3

ip 10.1.4.1 255.255.255.0 10.1.4.254

Example 3

Topology

  10.10.10.10/24   50.50.50.50/24     40.40.40.40/24 
    ┌───┐             ┌───┐                ┌───┐     
    │PC1│             │PC5│                │PC4│     
    └──┬┘             └─┬─┘                └─┬─┘     
       │VLAN10          │VLAN50              │VLAN40 
  10.10.10.0/24    50.50.50.0/24        40.40.40.0/24
    e1 │                │f1/0                │f1/2   
┌──────┴┐e0           ┌─┴┐              f1/0┌┴───┐   
│Switch1├─────────────┤R1├───60.60.60.0/24──┤ESW1│   
└──────┬┘         f3/0└──┘f2/0  VLAN1       └┬───┘   
    e2 │                                     │f1/1   
  20.20.20.0/24                         30.30.30.0/24
       │VLAN20                               │VLAN30 
    ┌──┴┐                                  ┌─┴─┐     
    │PC2│                                  │PC3│     
    └───┘                                  └───┘     
  20.20.20.20/24                      30.30.30.30/24

Topology of Example 3

Step by Step

on Router1:

Router, Cisco 3660 slot 0: Leopard-2FE slot 1-6: NM-1FE-TX

enable
conf ter

!disable interface 3/0's ip address. 
!We're using this interface as a 'trunk' port

interface fa 3/0
no ip address
no shutdown
exit

!set sub interfaces with VLAN

interface fa 3/0.10
encapsulation dot1Q 10
ip address 10.10.10.1 255.255.255.0
exit

interface fa 3/0.20
encapsulation dot1Q 20
ip address 20.20.20.1 255.255.255.0
exit

interface fa 1/0
no shutdown
ip address 50.50.50.1 255.255.255.0
exit


!TODO: SET F2/0 TO COMMUNICATE WITH ESW1

interface f 2/0
ip address 60.60.60.1 255.255.255.0
no shutdown
exit

ip route 30.30.30.0 255.255.255.0 60.60.60.2
ip route 40.40.40.0 255.255.255.0 60.60.60.2

end

on SW1:

L2 Switch, provided by GNS3

Set E0 Trunk dot1Q VLAN 1
set E1 Access VLAN 10
set E2 Access VLAN 20

on ESW1 :

EtherSwitch Router, Cisco 3660 slot 0:Leopard-2FE slot 1:NM-16ESW

enable

vlan database
vlan 30
vlan 40 exit

conf ter
interface f1/1
switchport mode access
switchport access vlan 30
exit

interface f1/2
switchport mode access
switchport access vlan 40
exit

interface vlan 30
ip address 30.30.30.1 255.255.255.0
exit

interface vlan 40
ip address 40.40.40.1 255.255.255.0
exit
ip routing

interface f 1/0
switchport mode trunk
switchport trunk allowed vlan all
exit

interface vlan 1
ip address 60.60.60.2 255.255.255.0
no shutdown
exit

ip route 10.10.10.0 255.255.255.0 60.60.60.1
ip route 20.20.20.0 255.255.255.0 60.60.60.1
ip route 50.50.50.0 255.255.255.0 60.60.60.1

end

on VPC1

ip 10.10.10.10/24 10.10.10.1

on VPC2

ip 20.20.20.20/24 20.20.20.1

on VPC3

ip 30.30.30.30/24 30.30.30.1

on VPC4

ip 40.40.40.40/24 40.40.40.1

on VPC5

ip 50.50.50.50/24 50.50.50.1