How to Configure Basic Traffic Shaping

When deploying traffic shaping, consider the CPU resources of the system. Especially on low-end machines, shaping on highly used links may cause performance degradation, resulting in high CPU loads and reduced network connectivity. Depending on the system configuration, Barracuda Networks recommends a maximum interface shaping bandwidth of 10 MB/s on systems with a CPU clock of 800MHz or lower.

There are different ways to configure traffic shaping on the Barracuda CloudGen Firewall. You can use the predefined Basic profile template or configure all settings manually (see How to Create a QoS Profile). The step-by-step instructions provided in this article explain how to configure basic traffic shaping. The basic traffic shaping scheme employs a simple virtual tree named Default with a single virtual interface named NoDelay attached to it.

Step 1. Apply the Basic Profile Template

1. Go to CONFIGURATION  > Configuration Tree > Box > Traffic Shaping.
2. Click Lock.
3. From the Predefined Profiles list at top of the page, select Basic profile.
4. Click Yes to apply the template.
5. From the Select Interface list, select the interface to which you want to apply the basic profile.
6. Click OK. This assigns the virtual tree to the interface.
7. From the Interfaces table, double-click an interface to configure its bandwidth limit.
8. In the Rate section of the Interface Tree Mapping window, select Enable Shaping and enter a limit for the inbound and outbound bandwidth.
9. Click OK.
10. Click Send Changes and Activate.

Step 2. Apply Traffic Shaping to Access Rules

Select the QoS Band in the Policy settings of an access or application rule.

1. Go to CONFIGURATION  > Configuration Tree > Box > Assigned Services > Firewall > Forwarding Rules.
2. Click Lock.
3. Create or double-click the access or application rule to which you are applying the QoS Band.
   • To apply the QoS Band to an access rule:

     • Select the QoS Band from the QoS Band (Fwd) and QoS Band (Reply) list in the Policy section. For more information, see How to Create and Apply QoS Bands.

       The outbound and inbound rate of a virtual interface is ignored when the QoS Band policy in the corresponding access rule is set to No-Shaping.

   • To apply a different QoS Band to an application rule
     
     • Select the Change QoS Band (Fwd) check box in the Policy section and select the QoS Band from the list.
4. Click OK.
5. Click Send Changes and Activate.