15.5. Configuring ingress cluster traffic for a service external IP
You can attach an external IP address to a service so that it is available to traffic outside the cluster. This is generally useful only for a cluster installed on bare metal hardware. The external network infrastructure must be configured correctly to route traffic to the service.
15.5.1. Prerequisites
- Your cluster is configured with ExternalIPs enabled. For more information, read Configuring ExternalIPs for services.
15.5.2. Attaching an ExternalIP to a service
You can attach an ExternalIP to a service. If your cluster is configured to allocate an ExternalIP automatically, you might not need to manually attach an ExternalIP to the service.
Procedure
Optional: To confirm what IP address ranges are configured for use with ExternalIP, enter the following command:
$ oc get networks.config cluster -o jsonpath='{.spec.externalIP}{"\n"}'
If
autoAssignCIDRs
is set, OpenShift Container Platform automatically assigns an ExternalIP to a newService
object if thespec.externalIPs
field is not specified.Attach an ExternalIP to the service.
If you are creating a new service, specify the
spec.externalIPs
field and provide an array of one or more valid IP addresses. For example:apiVersion: v1 kind: Service metadata: name: svc-with-externalip spec: ... externalIPs: - 192.174.120.10
If you are attaching an ExternalIP to an existing service, enter the following command. Replace
<name>
with the service name. Replace<ip_address>
with a valid ExternalIP address. You can provide multiple IP addresses separated by commas.$ oc patch svc <name> -p \ '{ "spec": { "externalIPs": [ "<ip_address>" ] } }'
For example:
$ oc patch svc mysql-55-rhel7 -p '{"spec":{"externalIPs":["192.174.120.10"]}}'
Example output
"mysql-55-rhel7" patched
To confirm that an ExternalIP address is attached to the service, enter the following command. If you specified an ExternalIP for a new service, you must create the service first.
$ oc get svc
Example output
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE mysql-55-rhel7 172.30.131.89 192.174.120.10 3306/TCP 13m