Docs

Volcengine Kubernetes Engine

Container Network

Configuring QoS bandwidth limits for pods

VKE clusters allow you to use annotations to configure QoS bandwidth limits for a pod, which prevents a high-traffic pod from slowing down the network transmission of the entire cluster. This topic describes how to configure QoS bandwidth limits for a pod.

Background information

In most cases, users deploy various types of workloads in a cluster, including online and offline workloads. Online pods are sensitive to network responses and require low network latency. You can prevent high-traffic pods (such as those involved in large-scale data transmission or abnormal requests) from consuming excessive bandwidth, as this can cause network latency and timeouts for other pods. To ensure network priority for core pods (such as payment and transaction pods) and prevent non-core pods from hogging bandwidth, you can use annotations to limit a single pod's bandwidth during deployment. This prevents network congestion. It also stops individual pods from slowing cross-node network transmission for the entire cluster, ensuring fair network resource allocation.

In VKE clusters, you can configure bandwidth limits for pods by using standard Kubernetes pod annotations.

Annotation	Description
kubernetes.io/egress-bandwidth: 1M	The outbound bandwidth limit for the pod. For example, 1 Mbps.

tip

VKE clusters currently support outbound bandwidth limits for pods but do not support inbound bandwidth limits.

Limits

This feature can be used only in clusters that use the VPC-CNI network model.

The vpc-cni add-on of v1.7.10 or later has been installed in the cluster. For details, see Upgrading add-ons.

Configuration examples

Create the YAML file of the workload. The code of the sample file deployment-demo.yaml is as follows:

apiVersion: apps/v1
kind: Deployment
metadata:
name: deployment-demo
namespace: default
spec:
replicas: 1
selector:
matchLabels:
app: demo
template:
metadata:
labels:
app: demo
annotations:
kubernetes.io/egress-bandwidth: 1M # Configure the outbound bandwidth limit for the pod. For example, 1M.
spec:
containers:
- name: demo
image: doc-cn-beijing.cr.volces.com/vke/nginx-demo:v1.0
ports:
- containerPort: 80
command: ["sleep", "3600"] # Keep the pod running for 1 hour for testing.

Run the following command to create the workload.

kubectl apply -f deployment-demo.yaml

Log in to the pod console and run the following command to test the pod bandwidth by using iperf. -c indicates that the client mode is used, and 192.168.1.126 indicates the IP address of the iperf server. The sample values in this topic are for reference only.

iperf3 -c 192.168.1.126

The following output is the expected result. The pod outbound bandwidth is limited to 1 Mbps, indicating that the pod QoS bandwidth limit feature has taken effect.

Connecting to host 192.168.1.126, port 5201
[ 5] local 192.168.1.131 port 57792 connected to 192.168.1.126 port 5201
[ ID] Interval Transfer Bitrate Retr Cwnd
[ 5] 0.00-1.00 sec 226 KBytes 1.85 Mbits/sec 0 29.7 KBytes
[ 5] 1.00-2.00 sec 127 KBytes 1.04 Mbits/sec 0 29.7 KBytes
[ 5] 2.00-3.00 sec 127 KBytes 1.04 Mbits/sec 0 29.7 KBytes
[ 5] 3.00-4.00 sec 127 KBytes 1.04 Mbits/sec 0 29.7 KBytes
[ 5] 4.00-5.00 sec 127 KBytes 1.04 Mbits/sec 0 29.7 KBytes
[ 5] 5.00-6.00 sec 127 KBytes 1.04 Mbits/sec 0 29.7 KBytes
[ 5] 6.00-7.00 sec 63.6 KBytes 521 Kbits/sec 0 29.7 KBytes
[ 5] 7.00-8.00 sec 127 KBytes 1.04 Mbits/sec 0 29.7 KBytes
[ 5] 8.00-9.00 sec 127 KBytes 1.04 Mbits/sec 0 29.7 KBytes
[ 5] 9.00-10.00 sec 127 KBytes 1.04 Mbits/sec 0 29.7 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-10.00 sec 1.28 MBytes 1.07 Mbits/sec 0 sender
[ 5] 0.00-10.03 sec 1.14 MBytes 956 Kbits/sec receiver

iperf Done.

Last updated: 2026.08.19 17:36:06