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Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 30 Configuring Layer 3 Interfaces
Configuring Logical Layer 3 VLAN Interfaces
Configuring Logical Layer 3 VLAN Interfaces
Note Before you can configure logical Layer 3 VLAN interfaces, you must create and configure the VLANs
on the switch, assign VLAN membership to the Layer 2 interfaces, enable IP routing if IP routing is
disabled, and specify an IP routing protocol.
To configure logical Layer 3 VLAN interfaces, perform this task:
This example shows how to configure the logical Layer 3 VLAN interface VLAN 2 and assign an IP
address:
Switch> enable
Switch# config term
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# vlan 2
Switch(config)# interface vlan 2
Switch(config-if)# ip address 10.1.1.1 255.255.255.248
Switch(config-if)# no shutdown
Switch(config-if)# end
This example shows how to use the show interfaces command to display the interface IP address
configuration and status of Layer 3 VLAN interface VLAN 2:
Switch# show interfaces vlan 2
Vlan2 is up, line protocol is down
Hardware is Ethernet SVI, address is 00D.588F.B604 (bia 00D.588F.B604)
Internet address is 172.20.52.106/29
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
Command Purpose
Step 1 Switch(config)# vlan vlan_ID Creates the VLAN.
Step 2 Switch(config)# interface vlan vlan_ID Selects an interface to configure.
Step 3 Switch(config-if)# ip address ip_address subnet_mask Configures the IP address and IP subnet.
Step 4 Switch(config-if)# no shutdown Enables the interface.
Step 5 Switch(config-if)# end Exits configuration mode.
Step 6 Switch# copy running-config startup-config Saves your configuration changes to NVRAM.
Step 7 Switch# show interfaces [type slot/interface]
Switch# show ip interfaces [type slot/interface]
Switch# show running-config interfaces [type
slot/interface]
Switch# show running-config interfaces vlan vlan_ID
Verifies the configuration.