Cisco 1720 Router 2 IP Addresses


Is is possible to assign 2 IP addresses from different subnets to a single ethernet port on a Cisco 1720 router?

If so, how is it done?


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it is possible you have to create subinterface
ip add IP1 mask

ip add IP2 mask

yvsupportAuthor Commented:


What is the syntax?

I have the following as the lines of config for the ethernet port on the router. What do I need to add?

interface FastEthernet0
 ip address
 speed 100
interface FastEthernet0.1
 ip address
 speed 100

interface FastEthernet0.2
 ip address <or any other IP and mask>
 speed 100
yvsupportAuthor Commented:
OK. Have tried to enter an IP address for the subinterface and I get the following:

"Configuring IP routing on a LAN subinterface is only allowed if that
subinterface is already configured as part of an IEEE 802.10, IEEE 802.1Q, or ISL vLAN."

any ideas?
you have to set a VLAN encapsulation
(config)> int fa0
(config-interface)>encap dot

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