Sample Network Topology

The assumption here is that there is one router acts as Internet gateway and one switch connecting the router and all LAN machines such as PC, printer, and server.

                                            Internet
                                               |
                                             Router
                                               |
                                               | 192.168.1.0/24
                                               |
                                       (Layer-2) Switch
                                        |      |      |
                                        |   Server 1  |
                                        |             |
                                        |             |
                                       PC 1       Printer 1

Sample Configuration

1. Internet Router

Assuming your Internet router receives IP address automatically from your ISP using a modem through DHCP, then following is one possible configuration. When you have different requirement such as PPPoE or static IP address, please check out the following FAQ to find the most suitable sample configuration for your Internet router.
Various Internet Gateway Sample Configurations

service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname Router
!
!
ip subnet-zero
no ip finger
ip dhcp excluded-address 192.168.1.1 192.168.1.30
!
ip dhcp pool insideDHCP
network 192.168.1.0 255.255.255.0
default-router 192.168.1.1
dns-server 4.2.2.5 4.2.2.6 4.2.2.66
!
!
!
!
!
interface Ethernet0
description Facing the ISP (the WAN)
ip address dhcp
ip nat outside
!
interface Ethernet1
description Facing my LAN
ip address 192.168.1.1 255.255.255.0
ip nat inside
!
interface Serial0
no ip address
shutdown
!
interface Serial1
no ip address
shutdown
!
ip nat inside source list 1 interface Ethernet0 overload
ip classless
no ip http server
!
access-list 1 permit 192.168.1.0 0.0.0.255
!
!
line con 0
exec-timeout 0 0
password 7 104308100F1E1C0C
logging synchronous
login
transport input none
line aux 0
password 7 082C4D4703100B10
login
line vty 0 4
password 7 050607062B45400E
login
!
end
 

2. Switch

Switch
 
vlan 1,11
!
!
interface FastEthernet0/1
description LAN 1
switchport access vlan 11
switchport mode access
!
interface FastEthernet0/2
description LAN 1
switchport access vlan 11
switchport mode access
!
interface FastEthernet0/3
description LAN 1
switchport access vlan 11
switchport mode access
!
interface Vlan1
description VLAN database management only
shutdown
!
interface Vlan11
description LAN 1 - Users
ip address 192.168.1.2 255.255.255.0
!
ip default-gateway 192.168.1.1
!
 

Check out the following FAQ for further illustration
»Cisco Forum FAQ »Should I use Layer-3 switch or router?

Discussion
»[HELP] multiple ip address

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by aryoba
last modified: 2011-06-24 12:13:30