Chapter 2. Configuring the node port service range
During cluster installation, you can configure the node port range to meet the requirements of your cluster. After cluster installation, only a cluster administrator can expand the range as a postinstallation task. If your cluster uses a large number of node ports, consider increasing the available port range according to the requirements of your cluster.
If you do not set a node port range during cluster installation, the default range of 30000-32768
applies to your cluster. In this situation, you can expand the range on either side, but you must preserve 30000-32768
within your new port range.
Red Hat has not performed testing outside the default port range of 30000-32768
. For ranges outside the default port range, ensure that you test to verify the expanding node port range does not impact your cluster. In particular, ensure that there is:
- No overlap with any ports already in use by host processes
- No overlap with any ports already in use by pods that are configured with host networking
If you expanded the range and a port allocation issue occurs, create a new cluster and set the required range for it.
If you expand the node port range and OpenShift CLI (oc
) stops working because of a port conflict with the OpenShift Container Platform API server, you must create a new cluster.
2.1. Expanding the node port range Copy linkLink copied to clipboard!
You can expand the node port range for your cluster. After you install your OpenShift Container Platform cluster, you cannot shrink the node port range on either side of the currently configured range.
Red Hat has not performed testing outside the default port range of 30000-32768
. For ranges outside the default port range, ensure that you test to verify that expanding your node port range does not impact your cluster. If you expanded the range and a port allocation issue occurs, create a new cluster and set the required range for it.
Prerequisites
-
Installed the OpenShift CLI (
oc
). -
Logged in to the cluster as a user with
cluster-admin
privileges. -
You ensured that your cluster infrastructure allows access to the ports that exist in the extended range. For example, if you expand the node port range to
30000-32900
, your firewall or packet filtering configuration must allow the inclusive port range of30000-32900
.
Procedure
To expand the range for the
serviceNodePortRange
parameter in thenetwork.config.openshift.io
object that your cluster uses to manage traffic for pods, enter the following command:oc patch network.config.openshift.io cluster --type=merge -p \ '{
$ oc patch network.config.openshift.io cluster --type=merge -p \ '{ "spec": { "serviceNodePortRange": "<port_range>" } }'
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<port_range>
-
specifies your expanded range, such as
30000-32900
.
TipYou can also apply the following YAML to update the node port range:
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network.config.openshift.io/cluster patched
network.config.openshift.io/cluster patched
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Verification
To confirm that the updated configuration is active, enter the following command. The update can take several minutes to apply.
oc get configmaps -n openshift-kube-apiserver config \ -o jsonpath="{.data['config\.yaml']}" | \ grep -Eo '"service-node-port-range":["[[:digit:]]+-[[:digit:]]+"]'
$ oc get configmaps -n openshift-kube-apiserver config \ -o jsonpath="{.data['config\.yaml']}" | \ grep -Eo '"service-node-port-range":["[[:digit:]]+-[[:digit:]]+"]'
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"service-node-port-range":["30000-32900"]
"service-node-port-range":["30000-32900"]
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