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update version of Pgpool
This guide will show you how to use KubeDB Ops-manager operator to update the version of Pgpool.
Before You Begin
At first, you need to have a Kubernetes cluster, and the
kubectlcommand-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using kind.Install
KubeDBProvisioner and Ops-manager operator in your cluster following the steps here.You should be familiar with the following
KubeDBconcepts:
To keep everything isolated, we are going to use a separate namespace called demo throughout this tutorial.
$ kubectl create ns demo
namespace/demo created
Note: YAML files used in this tutorial are stored in docs/examples/pgpool directory of kubedb/docs repository.
Prepare Postgres
Prepare a KubeDB Postgres cluster using this tutorial, or you can use any externally managed postgres but in that case you need to create an appbinding yourself. In this tutorial we will use 3 node Postgres cluster named ha-postgres.
Prepare Pgpool
Now, we are going to deploy a Pgpool =with version 4.4.5.
Deploy Pgpool:
In this section, we are going to deploy a Pgpool. Then, in the next section we will update the version using PgpoolOpsRequest CRD. Below is the YAML of the Pgpool CR that we are going to create,
apiVersion: kubedb.com/v1alpha2
kind: Pgpool
metadata:
name: pp-update
namespace: demo
spec:
version: "4.4.5"
replicas: 1
postgresRef:
name: ha-postgres
namespace: demo
deletionPolicy: WipeOut
Let’s create the Pgpool CR we have shown above,
$ kubectl create -f https://github.com/kubedb/docs/raw/v2024.8.21/docs/examples/pgpool/update-version/pp-update.yaml
pgpool.kubedb.com/pp-update created
Now, wait until pp-update created has status Ready. i.e,
$ kubectl get pp -n demo
NAME TYPE VERSION STATUS AGE
pp-update kubedb.com/v1alpha2 4.4.5 Ready 26s
We are now ready to apply the PgpoolOpsRequest CR to update this Pgpool.
update Pgpool Version
Here, we are going to update Pgpool from 4.4.5 to 4.5.0.
Create PgpoolOpsRequest:
In order to update the Pgpool, we have to create a PgpoolOpsRequest CR with your desired version that is supported by KubeDB. Below is the YAML of the PgpoolOpsRequest CR that we are going to create,
apiVersion: ops.kubedb.com/v1alpha1
kind: PgpoolOpsRequest
metadata:
name: pgpool-version-update
namespace: demo
spec:
type: UpdateVersion
databaseRef:
name: pp-update
updateVersion:
targetVersion: 4.5.0
Here,
spec.databaseRef.namespecifies that we are performing operation onpp-updatePgpool.spec.typespecifies that we are going to performUpdateVersionon our Pgpool.spec.updateVersion.targetVersionspecifies the expected version of the Pgpool4.5.0.
Let’s create the PgpoolOpsRequest CR we have shown above,
$ kubectl apply -f https://github.com/kubedb/docs/raw/v2024.8.21/docs/examples/pgpool/update-version/ppops-update.yaml
pgpoolopsrequest.ops.kubedb.com/pgpool-version-update created
Verify Pgpool version updated successfully :
If everything goes well, KubeDB Ops-manager operator will update the image of Pgpool object and related PetSets and Pods.
Let’s wait for PgpoolOpsRequest to be Successful. Run the following command to watch PgpoolOpsRequest CR,
$ watch kubectl get pgpoolopsrequest -n demo
Every 2.0s: kubectl get pgpoolopsrequest -n demo
NAME TYPE STATUS AGE
pgpool-version-update UpdateVersion Successful 93s
We can see from the above output that the PgpoolOpsRequest has succeeded. If we describe the PgpoolOpsRequest we will get an overview of the steps that were followed to update the Pgpool.
$ kubectl describe pgpoolopsrequest -n demo pgpool-version-update
Name: pgpool-version-update
Namespace: demo
Labels: <none>
Annotations: <none>
API Version: ops.kubedb.com/v1alpha1
Kind: PgpoolOpsRequest
Metadata:
Creation Timestamp: 2024-07-17T06:31:58Z
Generation: 1
Resource Version: 51165
UID: 1409aec6-3a25-4b2b-90fe-02e5d8b1e8c1
Spec:
Apply: IfReady
Database Ref:
Name: pp-update
Type: UpdateVersion
Update Version:
Target Version: 4.5.0
Status:
Conditions:
Last Transition Time: 2024-07-17T06:31:58Z
Message: Pgpool ops-request has started to update version
Observed Generation: 1
Reason: UpdateVersion
Status: True
Type: UpdateVersion
Last Transition Time: 2024-07-17T06:32:01Z
Message: Successfully paused database
Observed Generation: 1
Reason: DatabasePauseSucceeded
Status: True
Type: DatabasePauseSucceeded
Last Transition Time: 2024-07-17T06:32:07Z
Message: successfully reconciled the Pgpool with updated version
Observed Generation: 1
Reason: UpdatePetSets
Status: True
Type: UpdatePetSets
Last Transition Time: 2024-07-17T06:32:52Z
Message: Successfully Restarted Pgpool pods
Observed Generation: 1
Reason: RestartPods
Status: True
Type: RestartPods
Last Transition Time: 2024-07-17T06:32:12Z
Message: get pod; ConditionStatus:True; PodName:pp-update-0
Observed Generation: 1
Status: True
Type: GetPod--pp-update-0
Last Transition Time: 2024-07-17T06:32:12Z
Message: evict pod; ConditionStatus:True; PodName:pp-update-0
Observed Generation: 1
Status: True
Type: EvictPod--pp-update-0
Last Transition Time: 2024-07-17T06:32:47Z
Message: check pod running; ConditionStatus:True; PodName:pp-update-0
Observed Generation: 1
Status: True
Type: CheckPodRunning--pp-update-0
Last Transition Time: 2024-07-17T06:32:52Z
Message: Successfully updated Pgpool
Observed Generation: 1
Reason: UpdateDatabase
Status: True
Type: UpdateDatabase
Last Transition Time: 2024-07-17T06:32:52Z
Message: Successfully updated Pgpool version
Observed Generation: 1
Reason: Successful
Status: True
Type: Successful
Observed Generation: 1
Phase: Successful
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Starting 2m55s KubeDB Ops-manager Operator Start processing for PgpoolOpsRequest: demo/pgpool-version-update
Normal Starting 2m55s KubeDB Ops-manager Operator Pausing Pgpool databse: demo/pp-update
Normal Successful 2m55s KubeDB Ops-manager Operator Successfully paused Pgpool database: demo/pp-update for PgpoolOpsRequest: pgpool-version-update
Normal UpdatePetSets 2m46s KubeDB Ops-manager Operator successfully reconciled the Pgpool with updated version
Normal get pod; ConditionStatus:True; PodName:pp-update-0 2m41s KubeDB Ops-manager Operator get pod; ConditionStatus:True; PodName:pp-update-0
Normal evict pod; ConditionStatus:True; PodName:pp-update-0 2m41s KubeDB Ops-manager Operator evict pod; ConditionStatus:True; PodName:pp-update-0
Normal check pod running; ConditionStatus:False; PodName:pp-update-0 2m36s KubeDB Ops-manager Operator check pod running; ConditionStatus:False; PodName:pp-update-0
Normal check pod running; ConditionStatus:True; PodName:pp-update-0 2m6s KubeDB Ops-manager Operator check pod running; ConditionStatus:True; PodName:pp-update-0
Normal RestartPods 2m1s KubeDB Ops-manager Operator Successfully Restarted Pgpool pods
Normal Starting 2m1s KubeDB Ops-manager Operator Resuming Pgpool database: demo/pp-update
Normal Successful 2m1s KubeDB Ops-manager Operator Successfully resumed Pgpool database: demo/pp-update for PgpoolOpsRequest: pgpool-version-update
Now, we are going to verify whether the Pgpool and the related PetSets their Pods have the new version image. Let’s check,
$ kubectl get pp -n demo pp-update -o=jsonpath='{.spec.version}{"\n"}'
4.5.0
$ kubectl get petset -n demo pp-update -o=jsonpath='{.spec.template.spec.containers[0].image}{"\n"}'
mongo:4.0.5
$ kubectl get pods -n demo mg-standalone-0 -o=jsonpath='{.spec.containers[0].image}{"\n"}'
ghcr.io/appscode-images/pgpool2:4.5.0@sha256:2697fcad9e11bdc704f6ae0fba85c4451c6b0243140aaaa33e719c3af548bda1
You can see from above, our Pgpool has been updated with the new version. So, the update process is successfully completed.
Cleaning Up
To clean up the Kubernetes resources created by this tutorial, run:
kubectl delete pp -n demo pp-update
kubectl delete pgpoolopsrequest -n demo pgpool-version-update