Vlans Overview - Lenovo Flex System Fabric CN4093 Application Manual

VLANs Overview

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CN4093 Application Guide for N/OS 8.2
Setting up virtual LANs (VLANs) is a way to segment networks to increase
network flexibility without changing the physical network topology. With network
segmentation, each switch port connects to a segment that is a single broadcast
domain. When a switch port is configured to be a member of a VLAN, it is added
to a group of ports (workgroup) that belong to one broadcast domain.
Ports are grouped into broadcast domains by assigning them to the same VLAN.
Frames received in one VLAN can only be forwarded within that VLAN, and
multicast, broadcast, and unknown unicast frames are flooded only to ports in the
same VLAN.
The CN4093 automatically supports jumbo frames. This default cannot be
manually configured or disabled.
The CN4093 10Gb Converged Scalable Switch (CN4093) supports jumbo frames
with a Maximum Transmission Unit (MTU) of 9,216 bytes. Within each frame, 18
bytes are reserved for the Ethernet header and CRC trailer. The remaining space in
the frame (up to 9,198 bytes) comprise the packet, which includes the payload of
up to 9,000 bytes and any additional overhead, such as 802.1q or VLAN tags.
Jumbo frame support is automatic: it is enabled by default, requires no manual
configuration, and cannot be manually disabled.
Note: Jumbo frames are not supported for traffic sent to switch management
interfaces.