Supermicro SuperBlade SBM-GEM-X2C, Руководство пользователя

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Chapter 6: 1-Gb Ethernet Switch Firmware
6-3 VLAN
Virtual LAN (VLAN) is a technology used to create several independent logical networks
in a physical network. Hence, it reduces the size of the broadcast domain in a network.
Packets are forwarded within the same VLAN. It can also be used to combine several
network segments into a same group of networks that appear as a single LAN to create
a flexible and extensible LAN network system. The VLAN screen is shown in
Figure 6-8 .
The switch supports an 802.1Q tagging VLAN. All packets entering the port of a switch
only can be forwarded to a port that is a member of same VLAN. The ingress untagged
frames are tagged by a per-port default tag (PVID). The forwarding decision is based on
this assigned default PVID. If the ingress frames are 802.1Q tagged, the port won’t alter
the frames but will keep the frame’s VLAN information intact. Tagged frames are
forwarded according to a VID contained within the tag.
The switch also supports ingress filtering. The switch will examine the VLAN information
in the incoming packets header to determine whether to drop or forward the packets. If
the incoming frame has tagged VLAN information, the ingress port will check itself to
see if it is a member of the tagged VLAN. If it is not, the frame will be dropped. If it’s a
member of the tagged VLAN, then it will check the destination port to see if it is a
member of the tagged VLAN. If not, the frame is dropped. If the destination is a member
1519-9216 Bytes Rx
Pkts indicates received packets with a packet length that is between (includes)
1519 ~ 9216 bytes.
1519-9216 Bytes Tx
Pkts indicates transmitted packets with a packet length that is between
(includes) 1519 ~ 9216 bytes.
Figure 6-8. VLAN Screen
Table 6-3. Port Statistics Screen Controls (Continued)
Control Description