Networking Quality Of Service QoS Configuration

The networking Quality of Service (QoS) configuration feature in Private Cloud Director enables you to provide different networking service levels for your virtual machines. By using quality of service (QoS) policies, you can apply rate limits to egress and ingress traffic, and do similar networking QoS operations.

You can apply QoS policies to individually to ports. You can also apply QoS policies to a tenant network. When you do this, ports with no specific policy attached will inherit the network level QoS policy.

QoS Rules

The QoS policies in Private Cloud Director allow you to define following rules:

• bandwidth_limit: Provides bandwidth limitations on networks, ports or public (floating) IPs. If implemented, any traffic that exceeds the specified rate is dropped.

• minimum_bandwidth: Provides minimum bandwidth constraints on certain types of traffic. If implemented, best efforts are made to provide no less than the specified bandwidth to each port on which the rule is applied.

• dscp_marking: Marks network traffic with a Differentiated Services Code Point (DSCP) value.

Configure and Apply QoS Policies

Create a QoS policy:

pcdctl network qos policy create --share --project <project_ID> <policy_name>

Create new rules for the QoS policy:

pcdctl network qos rule create --type <rule-type> [rule properties] <policy_name>

Apply the policy to a port

pcdctl port set --qos-policy <policy_name> <port_name|port_ID>

Apply the policy to a network

pcdctl network set --qos-policy <policy_name> <network_name|network_ID>

QoS Rule Properties

Following table describes the various rule policies you can specify when creating QoS rules.

Policy	Description
max_kbps	The maximum rate (in Kbps) that the VM can send.
max_burst_kbps	The maximum amount of data (in kbits) that the port can send in an VM if the token buffer is full. The token buffer replenishes at a "max_kbps" rate. The burst value for TCP traffic can be set as 80% of desired bandwidth limit value. For example, if the bandwidth limit is set to 1000kbps then a burst value of 800kbps is sufficient.
min-kbps	The minimum bandwidth (in Kbps) guaranteed to a VM.
ingress/egress	The direction of traffic the rule is applied to. From the perspective of a VM, ingress indicates download, and egress indicates upload.
dscp-mark	Specifies the decimal value of a DSCP mark.