Port Traffic Controls

Overview

Overview

Feature

Default

Menu

CLI

Web

Jumbo Packets

Disabled

n/a

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n/a

 

 

 

 

 

This chapter includes:

■Jumbo Frames: Enables ports operating at 1 Gbps or 10 Gbps speeds to accept inbound frames of up to 9220 bytes when configured for jumbo traffic.

Jumbo Frames

Feature

Default

Menu

CLI

Web

display VLAN jumbo status

n/a

—

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—

configure jumbo VLANs

Disabled

—

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—

 

 

 

 

 

The Maximum Transmission Unit (MTU) is the maximum size IP frame the switch can receive for Layer 2 frames inbound on a port. The switch drops any inbound frames larger than the MTU allowed on the port. On ports operating at 10 Mbps or 100 Mbps, the MTU is fixed at 1522 bytes. However, ports operating at 1 Gbs or 10 Gbps speeds accept forward frames of up to 9220 bytes (including four bytes for a VLAN tag) when configured for jumbo traffic. You can enable inbound jumbo frames on a per-VLAN basis. That is, on a VLAN configured for jumbo traffic, all ports belonging to that VLAN and operating at 1 Gbs or 10 Gbps allow inbound jumbo frames of up to 9220 bytes. (Regardless of the mode configured on a given jumbo-enabled port, if the port is operating at only 10 Mbps or 100 Mbps, only frames that do not exceed 1522 bytes are allowed inbound on that port.)

Terminology

Jumbo Frame: An IP frame exceeding 1522 bytes in size. The maximum Jumbo frame size is 9220 bytes. (This size includes 4 bytes for the VLAN tag.)

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