Jumbo Frame Support - Cisco Catalyst 4500 Series Configuration Manual

Chapter 7 Configuring Interfaces
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Jumbo Frame Support

These sections describe jumbo frame support:
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Maximum Transmission Units
The Catalyst 4500 series switch allows you to configure a maximum of 32 different maximum
transmission unit (MTU) sizes system wide. This means that the maximum number of different MTU
sizes that you can configure with the system mtu, mtu, ip mtu, and ipv6 mtu command on all Layer 2
and Layer 3 interfaces combined is 32.
Also, the system stores the IPv4 and IPv6 MTU sizes configured on an interface separately. For every
system mtu command or per interface mtu command, two separate MTU values are stored, one for IPv4
and one for IPv6. This further reduces the number of slots available (out of 32). However, only a single
MTU value is stored for each ip mtu and ipv6 mtu commands.
If the new MTU value you are configuring is already present in the system (that is, configured on some
other interface), then no new slot(s) are allocated to store it again.
If the maximum limit of 32 is reached and an attempt is made to configure a new MTU size on a new
interface, the system only allows configuration to proceed if the new MTU size has previously been
configured on some interface. Otherwise, an error message is displayed and the default MTU size is
assigned to the interface being configured.
Jumbo Frame Support Overview
A jumbo frame is a frame larger than the default Ethernet size. Enable jumbo frame support by
configuring a larger-than-default MTU size on a port or interface.
OL-25340-01
Supervisor uplink ports
WS-X4306-GB: all ports
WS-X4232-GB-RJ: ports 1-2
WS-X4418-GB: ports 1-2
WS-X4412-2GB-TX: ports 13-14
WS-X4506-GB-T
the 4648-GB-RJ45V
WS-X4648-GB+RJ45V
WS-X4648-RJ45V-E
WS-X4648-RJ45V+E
WS-X4706-10GE
Maximum Transmission Units, page 7-25
Jumbo Frame Support Overview, page 7-25
Ethernet Ports, page 7-26
VLAN Interfaces, page 7-26
Software Configuration Guide—Release IOS XE 3.3.0SG and IOS 15.1(1)SG
Configuring Optional Interface Features
7-25