Cisco Catalyst switch
Creado el: 18/06/2009 04:53 PM según TCC - Última modificación: 4/08/2009 04:07 AM según TCC
The ability of various Cisco Catalyst switches to support different frame sizes depends on many factors, one of which is the
hardware and software involved. Certainmodules can support larger frame sizes than others, even within the same platform.
Additionally, maximum frame size support can also change based on the software version used.
Jumbo frames are frameslarger than the standard Ethernet frame size of 1518 bytes, which includes the Layer 2 header and Frame
Check Sequence (FCS). In other words, jumbo frames refer to Ethernet packets of up to 9000 bytesin size. In Catalyst 4500 series
switches, the Supervisor III and IV can handle packets up to a maximum size of 9198 bytes.
Jumbo frame support can be enabled on these types of interfaces:Port-channel interface
Switched Virtual Interface (SVI)
Physical interface (Layer 2 (L2) / (L3))
When the jumbo frame feature is enabled on a port, the port can switch large or jumbo frames. This featureoptimizes server-toserver
performance. The default Maximum Transmission Unit (MTU) frame size is 1548 bytes for all Ethernet ports. The MTU size is
increased to 9216 bytes when the jumbo frame featureis enabled on a port.
On a Cisco Catalyst 3750 series switch, the jumbo frames are supported on the Gigabit Ethernet ports. The MTU cannot be changed
on an individual interface. It mustbe set globally. The switch must be reset afterward in order for the MTU change to take effect.
Consider this example:
3750(config)#system mtu jumbo 9000
Note: The default MTU size is 1500 bytes.If a value is entered that is outside the allowed range for the specific type of interface, the
value is not accepted.
Refer to the Catalyst 3750 Series section of Jumbo/Giant Frame Support on...