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through the interface. Layer 2 trac is unaected by the shutdown command. One of the interfaces in the system must be in Layer 3
mode before you congure or enter a Layer 3 protocol mode (for example, OSPF).
Enable Layer 3 on an individual interface
INTERFACE mode
ip address
Enable the interface.
INTERFACE mode
no shutdown
Example of Error Due to Issuing a Layer 3 Command on a Layer 2 Interface
If an interface is in the incorrect layer mode for a given command, an error message is displayed (shown in bold). In the following example,
the ip address command triggered an error message because the interface is in Layer 2 mode and the ip address command is a
Layer 3 command only.
Dell(conf-if)#show config
!
interface TengigabitEthernet 1/2
no ip address
switchport
no shutdown
Dell(conf-if)#ip address 10.10.1.1 /24
% Error: Port is in Layer 2 mode Te 1/2.
Dell(conf-if)#
To determine the conguration of an interface, use the show config command in INTERFACE mode or the various show interface
commands in EXEC mode.
Conguring Layer 3 (Interface) Mode
To assign an IP address, use the following commands.
Enable the interface.
INTERFACE mode
no shutdown
Congure a primary IP address and mask on the interface.
INTERFACE mode
ip address ip-address mask [secondary]
The ip-address must be in dotted-decimal format (A.B.C.D) and the mask must be in slash format (/xx).
Add the keyword secondary if the IP address is the interface’s backup IP address.
Example of the show ip interface Command
You can only congure one primary IP address per interface. You can congure up to 255 secondary IP addresses on a single interface.
To view all interfaces to see with an IP address assigned, use the show ip interfaces brief command in EXEC mode as shown in
View Basic Interface Information.
To view IP information on an interface in Layer 3 mode, use the show ip interface command in EXEC Privilege mode.
Dell>show ip int vlan 58
Vlan 58 is up, line protocol is up
Internet address is 1.1.49.1/24
Broadcast address is 1.1.49.255
Address determined by config file
Interfaces
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