Chapter 4. Network verification for OpenShift Dedicated clusters
Network verification checks run automatically when you deploy an OpenShift Dedicated cluster into an existing Virtual Private Cloud (VPC) or create an additional machine pool with a subnet that is new to your cluster. The checks validate your network configuration and highlight errors, enabling you to resolve configuration issues prior to deployment.
You can also run the network verification checks manually to validate the configuration for an existing cluster.
4.1. Understanding network verification for OpenShift Dedicated clusters
When you deploy an OpenShift Dedicated cluster into an existing Virtual Private Cloud (VPC) or create an additional machine pool with a subnet that is new to your cluster, network verification runs automatically. This helps you identify and resolve configuration issues prior to deployment.
When you prepare to install your cluster by using Red Hat OpenShift Cluster Manager, the automatic checks run after you input a subnet into a subnet ID field on the Virtual Private Cloud (VPC) subnet settings page.
When you add a machine pool with a subnet that is new to your cluster, the automatic network verification checks the subnet to ensure that network connectivity is available before the machine pool is provisioned.
After automatic network verification completes, a record is sent to the service log. The record provides the results of the verification check, including any network configuration errors. You can resolve the identified issues before a deployment and the deployment has a greater chance of success.
You can also run the network verification manually for an existing cluster. This enables you to verify the network configuration for your cluster after making configuration changes. For steps to run the network verification checks manually, see Running the network verification manually.
4.2. Scope of the network verification checks
The network verification includes checks for each of the following requirements:
- The parent Virtual Private Cloud (VPC) exists.
- All specified subnets belong to the VPC.
-
The VPC has
enableDnsSupportenabled. -
The VPC has
enableDnsHostnamesenabled. - Egress is available to the required domain and port combinations that are specified in the AWS firewall prerequisites section.
4.3. Automatic network verification bypassing
You can bypass the automatic network verification if you want to deploy an OpenShift Dedicated cluster with known network configuration issues into an existing Virtual Private Cloud (VPC).
If you bypass the network verification when you create a cluster, the cluster has a limited support status. After installation, you can resolve the issues and then manually run the network verification. The limited support status is removed after the verification succeeds.
When you install a cluster into an existing VPC by using Red Hat OpenShift Cluster Manager, you can bypass the automatic verification by selecting Bypass network verification on the Virtual Private Cloud (VPC) subnet settings page.
4.4. Running the network verification manually
You can manually run the network verification checks for an existing OpenShift Dedicated cluster by using Red Hat OpenShift Cluster Manager.
Prerequisites
- You have an existing OpenShift Dedicated cluster.
- You are the cluster owner or you have the cluster editor role.
Procedure
- Navigate to OpenShift Cluster Manager and select your cluster.
- Select Verify networking from the Actions drop-down menu.
