Link aggregation

Introduction

Ethernet link aggregation bundles multiple physical Ethernet links into one logical link (called an aggregate link). Link aggregation provides the following benefits:

• Increased bandwidth beyond the limits of a single individual link. In an aggregate link, traffic is distributed across the member ports.

• Improved link reliability. The member ports dynamically back up one another. When a member port fails, its traffic is automatically switched to other member ports.

Aggregation mode

An aggregation group operates in one of the following modes:

• Static—Static aggregation is stable. The aggregation states of the member ports in a static aggregation group are not affected by the peer ports.

• Dynamic—Dynamic aggregation is implemented through IEEE 802.3ad Link Aggregation Control Protocol (LACP). The local system and the peer system automatically maintain the aggregation states of the member ports. Dynamic link aggregation reduces the administrators' workload.

Load sharing mode

The following load sharing modes are supported:

• Destination MAC-based load sharing

• Source MAC-based load sharing

• Destination IP-based load sharing

• Source IP-based load sharing

Application scenarios

As shown in Figure-1, Device A and Device B are connected by three physical Ethernet links. These physical Ethernet links are combined into an aggregate link called link aggregation 1. The bandwidth of this aggregate link can reach up to the total bandwidth of the three physical Ethernet links. At the same time, the three Ethernet links back up one another. When a physical Ethernet link fails, the traffic transmitted on the failed link is switched to the other two links.

Figure-1 Schematic diagram for link aggregation

Configuration guide

Procedure

Add an aggregation group and configure its basic configuration

1. From the left navigation pane, select Configure > Network Config > Interface > Link Aggregation.

2. Click Add on the link aggregation configuration page.

3. (Optional.) For the Aggregation type field, select an aggregation type for the aggregation group.

4. For the Aggregation mode field, select an aggregation mode for the aggregation group. Options include Static aggregation and Dynamic aggregation.

5. (Optional.) In the Description field, enter the description of the aggregation group.

6. Click Submit. To cancel the creation of the aggregation group, click Cancel.

Edit basic configuration of an existing aggregation group

1. From the left navigation pane, select Configure > Network Config > Interface > Link Aggregation > Aggregation configuration.

2. On the link aggregation configuration page, click Basic Configuration to expand the basic configuration page.

3. Click the Turn on aggregate interface toggle button to enable the aggregate interface.

4. From the Link Type dropdown list, select the link type for the aggregate interface.

5. In the PVID field, configure the VLAN ID for the aggregate interface. The default value is 1.

6. (Optional.) In the Description field, enter the description of the aggregation group.

7. For the Aggregation mode field, select an aggregation mode for the aggregation group. Options include Static aggregation and Dynamic aggregation.

8. In the Member ports area, assign ports to or remove ports from the aggregation group through configuring the ports in the Unselected area and Selected area.

   • The ports in the Unselected area are ports not assigned to any aggregation group. Select ports and then click the > button on the right to assign these ports to the aggregation group.

   • The ports in the Selected area are ports assigned to the aggregation group. Select any ports, and then click the < button on the left to remove these ports from the aggregation group.

9. From the Load sharing type list, select a load sharing type.

10. Click Go to Global Configuration to access the global load sharing type configuration page.

11. In the System LACP priority field, enter the system LACP priority.

12. From the Global load sharing type list, select a global load sharing type.

13. Click the Aggregated traffic redirection toggle button to enable link-aggregation traffic redirection.

14. Click Submit to complete configuring the global load sharing type. To cancel configuring the global load sharing type, click Cancel.

15. Click Submit to complete editing the aggregation group. To cancel editing the aggregation group, click Cancel.

Edit advanced configuration of an existing aggregation group

1. From the left navigation pane, select Configure > Network Config > Interface > Link Aggregation > Aggregation configuration.

2. On the link aggregation configuration page, click Advanced Configuration to expand the advanced configuration area.

3. In the Link attributes area, select whether to allow oversized frames to pass. In the Maximum Frame Size field, set the maximum frame length.

4. Click the Port status change log toggle button to enable or disable generating logs for link-up and link-down events when the state changes.

5. Click the Port status change SNMP alarm toggle button to enable or disable SNMP notifications for link state changes of interfaces.

6. In the Aggregation attributes area, select the maximum/minimum number of Selected ports by dragging the value bar, entering a value directly, or clicking the button.

Edit the member ports of an aggregation group

1. From the left navigation pane, select Configure > Network Config > Interface > Link Aggregation > Member port list.

2. On the member port list page, the member port list of the current aggregation group is displayed.

3. On the member port list page, click the icon in the Actions column for a member port to access the member port configuration page.

4. In the Port priority field, set the priority for this member port.

5. Click Submit to complete editing the member port configuration. To cancel editing the member port configuration, click Cancel.

6. On the member port list page, click the icon in the Actions column for a member port to delete that member port.