Bull 1GB Intel Ethernet Switch Module, Инструкция по установке и эксплуатации

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NovaScale Blade 1 GB Intel® Ethernet Switch Module: Installation and User’s Guide
each of the remaining network segments in accordance with IEEE 802.1D. Eventually, the packet is
made accessible to all nodes connected to the network.
This approach works well for broadcast packets that are intended to be seen or processed by all
connected nodes. In the case of multicast packets, however, this approach can lead to less efficient
use of network bandwidth, particularly when the packet is intended for only a small number of
nodes. Packets will be flooded onto network segments where no node has any interest in receiving
the packet. The problem of wasting bandwidth is even worse when the LAN segment is not shared,
for example in full duplex links.
Allowing switches to snoop IGMP packets is one way to solve this problem. The switch uses the
information in the IGMP packets as they are being forwarded throughout the network to determine
which segments should receive packets directed to particular group addresses.
Group addresses are stored in the Multicast Forwarding Database (MFDB). An IGMP address will
be removed from the database if a report for it is not received within the query interval. An interface
may be removed from an IGMP group in response to an IGMP Leave Group message.
Link aggregation (LAG)
The NovaScale Blade 1 GB Intel® Ethernet Switch Module supports Link Aggregation (LAG), or
port trunking. Port trunks (aggregated ports) can be used to increase the bandwidth of a network
connection or to ensure fault recovery.You can configure up to two trunk connections (combining
two to four ports into one fat pipe) between any two NovaScale Blade Chassiss or other Layer 2
switches. However, before making any physical connections between devices, use the Link
Aggregation commands to specify the ports that will belong to the trunking group on both switches.
When using a port trunk, note that:
•
The ports used in a trunk must all be of the same speed (100 Mbps or 1000 Mbps) and operate in
full-duplex mode only.
• The ports that can be assigned to the same trunk have certain other restrictions, as described in
this section.
• Each port can only be assigned to one trunk group, whether a static or dynamic group.
• The ports at both ends of a connection must be configured as trunk ports.
• All of the ports in a trunk have to be treated as a whole when moved from/to, added, or deleted
from a VLAN.
• The Spanning Tree Protocol (STP) will treat all the ports in a trunk as a whole.
• Enable the trunk before connecting any cable between the switches to avoid creating a data loop.
• Disconnect all trunk port cables or disable the trunk ports before removing a port trunk to avoid
creating a data loop.
Trunking can be set as a static or a dynamic port/group using the IEEE 802.3ad Link Aggregation
commands. When trunking is enabled, a blue border will be placed around the ports on the Web
device panel display.
Static LAGs
When you create a LAG, the member links will attempt to exchange LACPDUs with their partners.
If a link does not receive a LACPDU within 3 seconds, it will come up with default values. If a
LACPU is later received with different values, the link will drop out of the LAG. When all member