Shaper Template
The Shaper template provides a simplified way of globally configuring Quality of Service (QoS) on your appliances.
A shaper is a set of policies that control access and traffic flow on appliances by allocating bandwidth as a percentage of system bandwidth. Shaper parameters are organized into ten traffic classes. Four traffic classes are preconfigured (RealTime, CriticalApps, BulkApps, and Default). After compressing (deduplicating) all outbound tunnelized and passthrough-shaped traffic, Orchestrator either applies policy settings globally or upon each interface, shaping the traffic as it leaves the interface.
Applying the Shaper template to an appliance updates its system-level WAN shaper. Orchestrator preserves any interface-specific shapers that have been added. For minimum and maximum bandwidth, you can configure traffic class values as a percentage of total available system bandwidth and as an absolute value. The appliance always provides the larger of the minimum values and limits bandwidth to the lower of the maximum values. You can rename or edit any traffic class.
You can view applied configurations by navigating to Configuration > Templates & Policies > Shaping > Shaper. See Shaper Tab.
Add / Delete Shaper
To create an interface shaper, click Add Shaper. A shaper is defined only for a specified traffic direction (inbound or outbound).
To remove an interface shaper, click Delete Shaper. You cannot delete the Total WAN shapers (inbound or outbound).
Enable Interface Shaper
An outbound interface shaper is always enabled. You cannot clear the Enable shaping and Per interface check boxes for outbound interfaces.
Inbound interface shaping is disabled by default. To enable inbound traffic shaping, select the Enable shaping check box. To enable inbound interface shaping, select both the Enable shaping and Per Interface check boxes. For more information, see Per-interface Shaping below.
Shaper Options
| Option | Description |
|---|---|
| Inbound / Outbound | Enables you to select the direction to which to apply shaper configurations. Inbound (for WAN to LAN) Outbound (for LAN to WAN) |
| Shaper | Select the shaper to use, both for inbound and outbound traffic. By default, the selected shaper is Total WAN, which provides shaping against the total WAN bandwidth on the appliance. Because this shaper is generally sufficient, you should not need to use any other shapers. |
| Add Shaper | If desired, you can add a shaper. However, because the Total WAN shaper provided by Orchestrator is generally sufficient, you should not need to add other shapers. |
| Delete Shaper | Enables you to delete shapers you have explicitly added. |
| Enable shaping | Indicates whether to enable shaping of traffic. Shaping is always enabled for outbound traffic. Shaping for inbound traffic is recommended and best practice, but optional. |
| Per interface | Indicates whether to shape traffic on an individual interface level. It is recommended and best practice to select this option. Shaping is based on per-interface bandwidth and total system bandwidth. For more information, see Per-interface Shaping below. |
| Recalc on IF and/or nexthop reachability state change | Indicates whether to recalculate shaper bandwidth based on the loss of any WAN-side interface or next-hop reachability. It is recommended and best practice to select this option. |
| Enable Dynamic Rate Control | Indicates whether to enable Dynamic Rate Control (DRC). This feature prevents many-to-one bandwidth oversubscription. This option is available only for inbound traffic. For more information, see Dynamic Rate Control below. |
Shaper Configuration
| Field | Description |
|---|---|
| Traffic Name | Name assigned to the traffic class (by Orchestrator or the user). |
| Priority | Order in which to allocate each class’ minimum bandwidth. Valid values are 1 to 10 with 1 as first priority and 10 as last. |
| Min Bandwidth % | Minimum percentage of bandwidth guaranteed to the traffic class, allocated by priority. However, if the sum of the percentages is greater than 100%, lower-priority traffic classes might not receive their guaranteed bandwidth if it is all consumed by higher-priority traffic. Max overrides Min if you set Min Bandwidth % to a value greater than Max Bandwidth %. |
| Min Bandwidth Absolute (kbps) | Minimum bandwidth (in kbps) for the traffic class, which guarantees a minimum level of service when total system bandwidth declines. This is useful for maintaining, for example, the quality of VoIP. |
| Excess Weighting | If bandwidth remains after satisfying the minimum bandwidth percentages, the excess is distributed among the traffic classes in proportion to the weightings specified in this column. Valid values are 1 to 10,000. |
| Max Bandwidth % | Maximum percentage of bandwidth that a traffic class can use (as a percentage of total available system bandwidth). |
| Max Bandwidth Absolute (kbps) | Maximum bandwidth (in kbps) for the traffic class, which provides an absolute upper limit for bandwidth. This is useful for capping, for example, the bandwidth of downloads and streaming services. |
| Max Wait Time (ms) | Any packets waiting longer than this specified waiting time (in ms) are dropped. |
| Rate Limit (kbps) | Per-flow rate limit (in kbps) for the traffic class. For no limit, specify 0 (zero). |
Per-interface Shaping
When you select the Per interface check box, the appliance applies shaping per WAN interface for inbound traffic in addition to system-level shaping.
NOTE: For outbound traffic, shaping is inherently per interface because packets leave on a specific WAN link.
Shaping is handled in two layers: the system (appliance-wide) shaper enforces an aggregate bandwidth cap across all WAN interfaces while the per-interface shaper applies a cap separately on each WAN interface.
Each interface is shaped using that interface’s configured bandwidth. Traffic arriving on one link cannot exceed that link’s capacity or starve other links. If you do not select the Per interface check box, inbound shaping uses only the system-level aggregate rate. As a result, all interfaces share a single bandwidth cap, which can cause high-speed links to carry most of the traffic while overloads and increased loss can occur on lower-speed links. It is highly recommended that you always enable this feature for appliances with multiple WAN interfaces.
Dynamic Rate Control
Dynamic Rate Control (DRC) allows the EdgeConnect to prevent many-to-one bandwidth oversubscription by automatically adjusting per-flow bandwidth. If the EdgeConnect experiences congestion (drops or wait time), the EdgeConnect automatically regulates traffic by lowering each remote appliance’s per-flow rate. The following animation illustrates this process.
To enable this feature, select the Inbound filter, and then select the Enable Dynamic Rate Control check box on the Shaper template or the Shaper dialog box.
IMPORTANT: DRC is driven by QoS drops and shaper wait time. If you configure the EdgeConnect with an Inbound Shaper value greater than or equal to the service provider, the EdgeConnect will never see drops or wait time and your traffic will not receive the benefits of DRC.