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Meanwhile, the system with the higher system ID is aware of the aggregation state changes on
the peer system. The system sets the aggregation state of local member ports the same as their
peer ports.
Storm control
Storm control compares broadcast, multicast, and unknown unicast traffic regularly with their
respective traffic thresholds on an Ethernet interface. For each type of traffic, storm control provides
a lower threshold and an upper threshold.
Depending on your configuration, when a particular type of traffic exceeds its upper threshold, the
interface performs either of the following tasks:
•
No
action
—
Does not perform any actions on the interface.
•
Block
—Blocks this type of traffic and forwards other types of traffic. Even though the interface
does not forward the blocked traffic, it still counts the traffic. When the blocked traffic drops
below the lower threshold, the interface begins to forward the traffic.
•
Shutdown
—The interface goes down automatically and stops forwarding any traffic. When the
blocked traffic drops below the lower threshold, the interface does not automatically come up.
To bring up the interface, manually bring up the interface or disable the storm control function.
You can configure an Ethernet interface to output threshold event traps and log messages when
monitored traffic meets one of the following conditions:
•
Exceeds the upper threshold.
•
Drops below the lower threshold.
Port isolation
The port isolation feature isolates Layer 2 traffic for data privacy and security without using VLANs.
Ports in an isolation group cannot communicate with each other. However, they can communicate
with ports outside the isolation group.
VLAN
The Virtual Local Area Network (VLAN) technology breaks a LAN down into multiple logical LANs,
which is called VLANs. Each VLAN is a broadcast domain. Hosts in the same VLAN can directly
communicate with one another. Hosts in different VLANs are isolated from one another at Layer 2.
Port-based VLANs
Port-based VLANs group VLAN members by port. A port forwards packets from a VLAN only after it
is assigned to the VLAN.
You can configure a port as an untagged or tagged port of a VLAN.
•
To configure the port as an untagged port of a VLAN, assign it to the untagged port list of the
VLAN. The untagged port of a VLAN forwards packets from the VLAN without VLAN tags.
•
To configure the port as a tagged port of a VLAN, assign it to the tagged port list of the VLAN.
The tagged port of a VLAN forwards packets from the VLAN with VLAN tags.
You can configure the link type of a port as access, trunk, or hybrid. Ports of different link types use
different VLAN tag handling methods.
•
Access
—An access port can forward packets from only one VLAN and send them untagged.
Assign an access port to only the untagged port list of a VLAN.
