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Cisco Catalyst Blade Switch 3120 for HP Command Reference
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Chapter 2 Cisco Catalyst Blade Switch 3120 for HP Cisco IOS Commands
system mtu
system mtu
Use the
system mtu
global configuration command on the switch stack or on a standalone switch to set
the maximum packet size or maximum transmission unit (MTU) size for Gigabit Ethernet (10/100/1000)
ports, for 10-Gigabit ports, or for routed ports. Use the
no
form of this command to restore the global
MTU value to its default value.
system mtu
{
jumbo
bytes |
routing
bytes
}
no system mtu
[
jumbo
|
routing
]
Syntax Description
Defaults
The default MTU size for all ports is 1500 bytes.
The default value for the system routing MTU is the system MTU value.
Command Modes
Global configuration
Command History
Usage Guidelines
The switch does not support the MTU on a per-interface basis.
When you use the
system
mtu jumbo
bytes
command to change the system MTU or system jumbo MTU
size, you must reset the switch before the new configuration takes effect. The
system mtu routing
command does not require a switch reset to take effect.
The system MTU jumbo setting is saved in the switch environmental variable in NVRAM and becomes
effective when the switch reloads. Unlike the system MTU routing configuration, the MTU settings that
you enter with the
system mtu jumbo
command is not saved in the switch Cisco IOS configuration file,
even if you enter the
copy running-config startup-config
privileged EXEC command. Therefore, if you
use TFTP to configure a new switch by using a backup configuration file and want the system MTU to
be other than the default, you must explicitly configure the
system mtu jumbo
settings on the new
switch and then reload the switch.
jumbo
bytes
Set the system MTU for Gigabit Ethernet ports and 10-Gigabit Ethernet
ports. The system jumbo MTU is the maximum MTU received at the Gigabit
Ethernet and 10-Gigabit Ethernet ports.
The range is from 1500 to 9198 bytes.
routing
bytes
Set the maximum MTU for routed packets. You can also set the maximum
MTU to be advertised by the routing protocols that support the configured
MTU size. The system routing MTU is the maximum MTU for routed
packets and is also the maximum MTU that the switch advertises in routing
updates for protocols such as OSPF.
The range is from 1500 to the system jumbo MTU value (in bytes).
Release
Modification
12.2(40)EX1
This command was introduced.
