QoS rule components (reference)

QoS rules consist of several key components that control traffic rate limiting and filtering behavior. Understanding these components helps you configure effective quality of service policies.

QoS rules include these main components:

  • State (Enabled/Disabled): Controls whether the rule is active and enforced by the system.

  • Interfaces (Apply QoS On): Specifies which interfaces the rate limiting applies to.

  • Traffic Limit Per Interface: Sets the rate limiting values for matching traffic.

  • Conditions: Defines the traffic criteria that must be matched for the rule to apply.

  • Comments: Provides documentation and change tracking for the rule.

State (Enabled/Disabled)

By default, rules are enabled. If you disable a rule, the system does not use it and stops generating warnings and errors for that rule.

Interfaces (apply QoS on)

You cannot save a QoS rule that rate limits all traffic. For each QoS rule, apply QoS on one of the options:

  • Interfaces in Source Interface Objects—Rate limits traffic through the rule's source interfaces. If you choose this option, you must add at least one source interface constraint (cannot be any).

  • Interfaces in Destination Interface Objects—Rate limits traffic through the rule's destination interfaces. If you choose this option, you must add at least one destination interface constraint (cannot be any).

Traffic limit per interface

A QoS rule enforces rate limiting independently on each interface specified with the Apply QoS On option. Aggregate rate limits cannot be applied to a group of interfaces.

You can rate limit traffic by Mbits per second. The default value of Unlimited prevents matching traffic from being rate limited.

You can independently rate limit download and upload traffic. The system determines download and upload directions based on the connection initiator.

If you specify a limit greater than the interface's maximum throughput, the system does not rate limit matching traffic. Maximum throughput may be affected by an interface's hardware configuration, which you specify in each device's properties (Devices > Device Management).

Conditions

Conditions specify the specific traffic that the rule handles. You can configure each rule with multiple conditions. Traffic must meet all conditions to match the rule. Each condition type has its own tab in the rule editor. For more information, see QoS rule conditions.

Comments

Each time you save changes to a rule, add comments. You might summarize the overall configuration for users, or note any changes made and the reasons.

In the policy editor, the system displays how many comments a rule has. In the rule editor, use the Comments tab to view existing comments and add new ones.