Blade ICE G8124 Manuale Utente

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BLADEOS 6.5.2 Application Guide
88  

  Chapter 6: VLANs
BMD00220, October 2010
VLANs Overview
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 RackSwitch G8124 (G8124) 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.
VLANs and Port VLAN ID Numbers
VLAN Numbers
The G8124 supports up to 1024 VLANs per switch. Even though the maximum number of VLANs 
supported at any given time is 1024, each can be identified with any number between 1 and 4094. 
VLAN 1 is the default VLAN for the data ports. VLAN 4095 is used by the management network, 
which includes the management port. 
Use the following command to view VLAN information: 
RS G8124# show vlan
VLAN
Name
Status
Ports
----
------------------------
------
-------------------------
1
Default VLAN
ena
1-24
2
VLAN 2
dis
empty
4095
Mgmt VLAN
ena
MGMTA MGMTB