Extreme Networks ExtremeWare 7.5, Command Reference Manual

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configure jumbo-frame size
ExtremeWare 7.5 Command Reference Guide 255
configure jumbo-frame size
configure jumbo-frame size <number>
Description
This command sets the maximum jumbo frame size for the switch chassis.
Syntax Description
Default
The default setting is 9216.
Usage Guidelines
Jumbo frames are used between endstations that support larger frame sizes for more efficient transfers
of bulk data. Both endstations involved in the transfer must be capable of supporting jumbo frames.
The
number
keyword describes the maximum jumbo frame size “on the wire,” and includes 4 bytes of
cyclic redundancy check (CRC) plus another 4 bytes if 802.1Q tagging is being used.
To enable jumbo frame support, you must configure the maximum transmission unit (MTU) size of a
jumbo frame that will be allowed by the switch.
Some network interface cards (NICs) have a configured maximum MTU size that does not include the
additional 4 bytes of CRC. Ensure that the NIC maximum MTU size is at or below the maximum MTU
size configured on the switch. Frames that are larger than the MTU size configured on the switch are
dropped at the ingress port.
For MPLS modules: You should enable jumbo frame support on the ports that are members of an
MPLS VLAN. The jumbo frame size should be set to accommodate the addition of a maximally-sized
label stack. For example, a jumbo frame size of at least 1530 bytes is needed to support a two-level label
stack on a tagged Ethernet port and a jumbo frame size of at least 1548 bytes is needed to support a TLS
encapsulated MPLS frame.
The MPLS module supports the MTU size configured using the
configure jumbo-frame size
command.
For version 6.1 and later:
• The jumbo_frame_mtu range is between 1523 through 9216.
For version 6.0:
• The jumbo_frame_mtu range is between 1522 through 9216.
Example
The following command configures the maximum MTU size of a jumbo frame size to 5500:
configure jumbo-frame size 5500
number Specifies a maximum transmission unit (MTU) size for a jumbo frame.