This section describes how to increase or decrease the number of OUDSM pods in the Kubernetes deployment.
By default the oudsm helm chart deployment starts one pod: oudsm-1.
The number of pods started is determined by the replicaCount, which is set to 1 by default. A value of 1 starts the pod above.
To scale up or down the number of OUDSM pods, set replicaCount accordingly.
Run the following command to view the number of pods in the OUDSM deployment:
$ kubectl --namespace <namespace> get pods -o wide
For example:
$ kubectl --namespace oudsmns get pods -o wide
The output will look similar to the following:
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/oudsm-1 1/1 Running 0 73m 10.244.0.19 <worker-node> <none> <none>
In this example, replicaCount is increased to 2 which creates a new OUDSM pod oudsm-2 with associated services created.
You can scale up the number of OUDSM pods using one of the following methods:
Navigate to the $WORKDIR/kubernetes/helm directory:
$ cd $WORKDIR/kubernetes/helm
Create a oudsm-scaleup-override.yaml file that contains:
replicaCount: 2
Run the following command to scale up the OUDSM pods:
$ helm upgrade --namespace <namespace> \
--values oudsm-scaleup-override.yaml \
<release_name> oudsm --reuse-values
For example:
$ helm upgrade --namespace oudsmns \
--values oudsm-scaleup-override.yaml \
oudsm oudsm --reuse-values
--set argumentRun the following command to scale up the OUDSM pods:
$ helm upgrade --namespace <namespace> \
--set replicaCount=2 \
<release_name> oudsm --reuse-values
For example:
$ helm upgrade --namespace oudsmns \
--set replicaCount=2 \
oudsm oudsm --reuse-values
Verify the new OUDSM pod oudsm-2 has started:
$ kubectl get pod,service -o wide -n <namespace>
For example:
$ kubectl get pods,service -n oudsmns
The output will look similar to the following:
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/oudsm-1 1/1 Running 0 88m 10.244.0.19 <worker-node> <none> <none>
pod/oudsm-2 1/1 Running 0 15m 10.245.3.45 <worker-node> <none> <none>
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
service/oudsm-1 ClusterIP 10.96.108.200 <none> 7001/TCP,7002/TCP 88m app.kubernetes.io/instance=oudsm,app.kubernetes.io/name=oudsm,oudsm/instance=oudsm-1
service/oudsm-2 ClusterIP 10.96.31.201 <none> 7001/TCP,7002/TCP 15m app.kubernetes.io/instance=oudsm,app.kubernetes.io/name=oudsm,oudsm/instance=oudsm-2
service/oudsm-lbr ClusterIP 10.96.41.201 <none> 7001/TCP,7002/TCP 73m app.kubernetes.io/instance=oudsm,app.kubernetes.io/name=oudsm
Note: It will take several minutes before all the services listed above show. While the oudsm-2 pod has a STATUS of 0/1 the pod is started but the OUDSM server associated with it is currently starting. While the pod is starting you can check the startup status in the pod log, by running the following command:
$ kubectl logs oudsm-2 -n oudsmns
Scaling down OUDSM pods is performed in exactly the same as in Scaling up OUDSM pods except the replicaCount is reduced to the required number of pods.
Once the kubectl command is executed the pod(s) will move to a Terminating state. In the example below replicaCount was reduced from 2 to 1 and hence oudsm-2 has moved to Terminating:
$ kubectl get pods -n oudsmns
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/oudsm-1 1/1 Running 0 92m 10.244.0.19 <worker-node> <none> <none>
pod/oudsm-2 1/1 Terminating 0 19m 10.245.3.45 <worker-node> <none> <none>
The pod will take a minute or two to stop and then will disappear:
$ kubectl get pods -n oudsmns
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
pod/oudsm-1 1/1 Running 0 94m 10.244.0.19 <worker-node> <none> <none>