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LACP

Link Aggregation Control Protocol (LACP) allows the dynamic exchange of information about the link aggregation between two members of port link aggregation.

Settings

Assign a System priority to run with LACP and become a backup link if a link goes down. If a link goes down, the lowest system priority can decide which ports it participates in. When the same LACP port priority is assigned to two or more ports, the port with the lowest physical port number is selected as the backup port. If a LAG already exists with the maximum number of allowed port members, and LACP is subsequently turned on for another port using a higher priority than an existing member, the newly configured port will replace the existing port member that has a lower priority. A smaller number indicates a higher priority level. The System priority range is from 1 to 65535, and the default is 32768.

To configure LACP settings, do as follows:

  1. Go to Configure > Link aggregation > LACP > Settings.
  2. Enter a System Priority. The default is 32768, and the range is from 1 to 65535.

  3. Select a System Policy from the drop-down list. The following options are available:

    • src-mac: The switch distributes traffic using the source MAC address. Packets from different hosts use different ports in the channel, but packets from the same host use the same port.
    • dest-mac: The switch distributes traffic using the destination MAC address. Packets to the same destination use the same port, but packets to different destinations use different ports.
    • src-dest-mac: The switch distributes traffic based on the source and destination MAC addresses.
    • src-ip: The switch distributes traffic using the source IP address.
    • dest-ip: The switch distributes traffic using the destination IP address.
    • src-dest-ip: The switch distributes traffic using the source and destination IP addresses.
    • dest-l4-port: The switch distributes traffic using the destination Layer 4 port.
    • src-l4-port: The switch distributes traffic using the source Layer 4 port.

  4. Click Apply.

Timeout

The LACP timeout value is measured at periodic intervals. When the interval expires, the port is removed from the trunk. For busy trunked links, set a short timeout, for example, one second, to make sure that disabled ports are removed from the trunk group as soon as possible. The default value for LACP timeout is Long timeout.

To configure LACP timeout, do as follows:

  1. Go to Configure > Link aggregation > LACP > Timeout.
  2. Select the port you want to configure.
  3. Click Edit.
  4. Select the Time-out from the drop-down list.
  5. Click Apply.