Cisco CATALYST 2960 - Configuring the System Mtu

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Catalyst 2960 and 2960-S Switches Software Configuration Guide, Release 15.0(1)SE
OL-26520-01
Chapter 12 Configuring Interface Characteristics
Configuring Layer 3 SVIs
Configuring Layer 3 SVIs
Note Only switches running the LAN base image support Layer 3 SVIs for static routing.
You should configure SVIs for any VLANs for which you want to route traffic. SVIs are created when
you enter a VLAN ID following the interface vlan global configuration command. To delete an SVI,
use the no interface vlan global configuration command. You cannot delete VLAN 1.
Note When you create an SVI, it does not become active until you associate it with a physical port.
For information about assigning Layer 2 ports to VLANs, see Chapter 13, “Configuring
VLANs.”
A Layer 3 switch can have an IP address assigned to each SVI, but the switch supports static routing on
16 SVIs. All Layer 3 interfaces require an IP address to route traffic. This procedure shows how to
configure an interface as a Layer 3 interface and how to assign an IP address to an interface.
Beginning in privileged EXEC mode, follow these steps to configure a Layer 3 SVI:
To remove an IP address from an SVI, use the no ip address interface configuration command.
This example shows how to configure a Layer 3 SVI and to assign it an IP address:
Switch# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# interface vlan 33
Switch(config-if)# ip address 192.20.135.21 255.255.255.0
Configuring the System MTU
The default maximum transmission unit (MTU) size for frames received and transmitted on all interfaces
is 1500 bytes. You can increase the MTU size for all interfaces operating at 10 or 100 Mb/s by using the
system mtu global configuration command. You can increase the MTU size to support jumbo frames on
all Gigabit Ethernet interfaces by using the system mtu jumbo global configuration command.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
interface vlan vlan-id Specify the VLAN to be configured as a Layer 3 SVI,
and enter interface configuration mode.
Step 3
ip address ip_address subnet_mask Configure the IP address and IP subnet.
Step 4
end Return to privileged EXEC mode.
Step 5
show interfaces [interface-id]
show ip interface [interface-id]
show running-config interface [interface-id]
Verify the configuration.
Step 6
copy running-config startup-config (Optional) Save your entries in the configuration file.