How Do I Locate the Fault When a Cluster Is Unavailable?

Possible causes are listed in order of likelihood.

If the fault persists after you have ruled out a cause, check other causes.

• Check Item 1: Whether the Security Group Is Modified
• Check Item 2: Whether the Cluster Is Overloaded

If the fault persists, contact the customer service to help you locate the fault.

1. Log in to the management console and choose Service List > Networking > Virtual Private Cloud. In the navigation pane, choose Access Control > Security Groups and find the security group of the master node in the cluster.

   The name of this security group is in the format of cluster_name-cce-control-ID.

2. Click the security group. On the details page displayed, ensure that the security group rules of the master node are correct.

   For details, see How Do I Modify Cluster Security Group Rules?

Symptom

The resource usage on the master nodes in the cluster reaches 100%.

Possible Cause

When a cluster has a large number of resources created simultaneously, it causes an overload on the API server. This, in turn, overloads the master nodes and leads to OOM issues.

Solution

Increase the cluster management scale. A larger cluster management scale means higher capacity and improved performance of the master nodes. For details, see Changing Cluster Scale.

If a cluster is overloaded, you can submit a service ticket for technical support.