C921-4P Lan Port Static IP addresses

[snwhi]

I am trying to connect three servers with static IP addresses on the LAN Ports (0-3) of a C921. If I try to assign a static IP address to Port 0, it is refused with a message stating the an IP address cannot be assigned to a Layer 4 port. Is there a command to change this (Layer 4) configuration?

[Enes Simnica]

hello. The Cisco C921’s gig ports operate as Layer 2 (switchports) by default, which is why you're unable to assign an IP address directly. To configure the port as a Layer 3 (routed) port, you need to use then ow switchport command, which removes the Layer 2 functionality, enabling you to assign an IP address.

After converting it to Layer 3, you can configure the static IP.

conf t
int g0/0
no switchport
ip address ....

-Enes

[amikat · Accepted solution]

Hi,

You cannot assign an IP address to four Gigabit Ethernet LAN ports. The routing between the 4-port managed switch and WAN ports is performed via the switch virtual interface (SVI), ie. Interface Vlan. You configure "interface Vlan x", assign IP address to it and then assign a LAN port with "switchport access vlan x". Please see the details at the Configuration Guide as per beneath:

https://www.cisco.com/c/en/us/td/docs/routers/access/900/software/configuration/guide/900SCG.pdf

Best regards,

Antonin