Load Balancing options for WAN circuits

Bigleaf enables you to configure how network traffic is routed to WAN circuits, called Load Balancing. You can let Bigleaf decide how traffic is routed among your circuits, or you can decide whether to allow traffic to access a circuit in only specific cases.

Accessing the Load Balance options

1. Log in to the Bigleaf Web Dashboard with an Admin account.
2. Select the Configuration tab for the site you want to edit, and then select Edit.
3. Scroll down to the Circuits settings, locate the WAN circuit you want to configure, and select Show Advanced Options.
4. Under Circuit Usage, select your Load Balance setting, and then select Save.
   
   

Load Balance

This option allows the Bigleaf service to dynamically route traffic in real-time based on observed circuit conditions and detected traffic type. It’s generally best to let Bigleaf’s dynamic Quality of Service (QoS) system make the decisions about which circuit to use. The Load Balancing system is designed to work with no custom configuration in most circumstances. This is the recommended setting.

Avoid

This option routes traffic based on the type of traffic it is. To some extent, the Avoid setting prevents Bigleaf’s traffic algorithm from freely choosing a circuit. The router will prefer Load Balance circuits even when Avoid circuits are healthy.

Our algorithms will not route traffic over an avoided circuit unless minimum alarm levels occur on other Load Balance circuits. For example, a circuit set to Avoid for the VoIP traffic class could still get VoIP traffic if a Load Balance circuit produces a Level-1 packet loss alarm, since VoIP traffic is handled sensitively. For this reason, we sometimes say that Avoid mode is halfway between the Load Balance and Backup Only modes.

These are the minimum alarm levels that must occur to route traffic to an avoided circuit:

• VoIP traffic will be routed to an avoided circuit if the other circuits are at a Level 1 packet loss or Level 2 for any other alarm.
• General traffic will be routed to an avoided circuit at Level 3 of any alarm.
• High throughput traffic will be routed to an avoided circuit at Level-4 packet loss or Level-5 of any alarm.

Backup Only

When setting a circuit to Backup Only, you lose the ability to automatically load balance traffic over multiple circuits, since a Backup Only circuit is used only in a failover situation, when all other circuits are completely down. Even if other circuits are performing very poorly, they will continue to be used until they are completely offline. This can result in poor performance throughout a site.

The Backup Only setting uses half as much data for Bigleaf circuit monitoring -- only 2GB per month instead of 5GB per month. This mode is helpful to minimize traffic over a 4G LTE or other metered link to lower link costs. You can monitor throughput and circuit alarm levels for a circuit configured as Backup Only on the Web Dashboard.

Custom Settings - Block

This setting allows you to configure how specific classes of traffic are handled on a WAN circuit, for example, VoIP, Real-Time, Urgent, Bulk Data, and more.

If you select Block mode for a specific traffic class on a circuit, all such traffic will be blocked from using that circuit. That traffic will be sent over any other circuit that is available. However, if the circuit where the traffic class is blocked is the only circuit available because all other circuits are down, all traffic in that traffic class will remain blocked until other circuits are restored.

For example, if you have a metered cellular circuit, and you set the Bulk Data traffic class to Block, if all other circuits are down, then large file downloads and bulk video streaming such as Netflix would not be able to pass through that circuit. If you want to use Block mode, we recommend testing it to ensure that your critical applications will work properly and that nothing necessary is unintentionally blocked.