15.4. Configuring ingress cluster traffic using a load balancer

Procedure

1. Create a new project for your service:

   $ oc new-project <project_name>

   For example:

   $ oc new-project myproject

2. Use the oc new-app command to create a service. For example:

   $ oc new-app \
       -e MYSQL_USER=admin \
       -e MYSQL_PASSWORD=redhat \
       -e MYSQL_DATABASE=mysqldb \
       registry.redhat.io/rhscl/mysql-80-rhel7

3. Run the following command to see that the new service is created:

   $ oc get svc -n myproject

   Example output

   NAME             TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)    AGE
   mysql-80-rhel7   ClusterIP   172.30.63.31   <none>        3306/TCP   4m55s

   By default, the new service does not have an external IP address.

1. Log in to OpenShift Container Platform.

2. Log in to the project where the service you want to expose is located:

   $ oc project myproject

3. Run the following command to expose the route:

   $ oc expose service <service_name>

   For example:

   $ oc expose service mysql-80-rhel7

   Example output

   route "mysql-80-rhel7" exposed

4. Use a tool, such as cURL, to make sure you can reach the service using the cluster IP address for the service:

   $ curl <pod_ip>:<port>

   For example:

   $ curl 172.30.131.89:3306

   The examples in this section uses a MySQL service, which requires a client application. If you get a string of characters with the Got packets out of order message, you are connected to the service.

   If you have a MySQL client, log in with the standard CLI command:

   $ mysql -h 172.30.131.89 -u admin -p

   Example output

   Enter password:
   Welcome to the MariaDB monitor.  Commands end with ; or \g.
   
   MySQL [(none)]>

1. Log in to OpenShift Container Platform.

2. Load the project where the service you want to expose is located.

   $ oc project project1

3. Open a text file on the master node and paste the following text, editing the file as needed:

   Sample load balancer configuration file

   apiVersion: v1
   kind: Service
   metadata:
     name: egress-2 1
   spec:
     ports:
     - name: db
       port: 3306 2
     loadBalancerIP:
     type: LoadBalancer 3
     selector:
       name: mysql 4

   1

   Enter a descriptive name for the load balancer service.

   2

   Enter the same port that the service you want to expose is listening on.

   3

   Enter loadbalancer as the type.

   4

   Enter the name of the service.

4. Save and exit the file.

5. Run the following command to create the service:

   $ oc create -f <file-name>

   For example:

   $ oc create -f mysql-lb.yaml

6. Execute the following command to view the new service:

   $ oc get svc

   Example output

   NAME       TYPE           CLUSTER-IP      EXTERNAL-IP                             PORT(S)          AGE
   egress-2   LoadBalancer   172.30.22.226   ad42f5d8b303045-487804948.example.com   3306:30357/TCP   15m

   The service has an external IP address automatically assigned if there is a cloud provider enabled.

7. On the master, use a tool, such as cURL, to make sure you can reach the service using the public IP address:

   $ curl <public-ip>:<port>

   For example:

   $ curl 172.29.121.74:3306

   The examples in this section use a MySQL service, which requires a client application. If you get a string of characters with the Got packets out of order message, you are connecting with the service:

   If you have a MySQL client, log in with the standard CLI command:

   $ mysql -h 172.30.131.89 -u admin -p

   Example output

   Enter password:
   Welcome to the MariaDB monitor.  Commands end with ; or \g.
   
   MySQL [(none)]>