The PostgreSQL Operator provides a Kubernetes operator capability for managing PostgreSQL Clusters deployed within a Kubernetes environment.
The PostgreSQL Operator leverages Kubernetes Custom Resource Definitions to define custom resource types such as:
-
pgcluster
-
pgbackups
-
pgpolicies
Once those custom objects are defined, Kubernetes provides the ability to create and manage those objects similar to any other native Kubernetes object.
The PostgreSQL Operator runs within Kubernetes detecting these new custom object types being created, updated, or removed.
Once the objects are detected, the PostgreSQL Operator enables users to perform operations across the Kubernetes environment, including:
-
Create a PostgreSQL Cluster
-
Destroy a PostgreSQL Cluster
-
Backup a PostgreSQL Cluster
-
Scale a a PostgreSQL Cluster
-
Restore a PostgreSQL Cluster
-
Upgrade a PostgreSQL Cluster
-
View PVC
-
Test Connections to a PostgreSQL Cluster
-
Create a SQL-based Policy
-
Apply a SQL-based Policy to a PostgreSQL Cluster
-
Perform User Management
-
Apply User Defined Labels to PostgreSQL Clusters
-
Perform Password Management
CRD (custom resource definitions) are supported starting with Kube 1.7.X. NOTE: Along with this new major version, changes were made to the configuration settings from the prior version of the Operator.
If you require an older version of Kube (< 1.7), you can work with the operator version 1.5.2 which resides in the github 1.5.X branch. Note however, that the older operator will be deprecated and no longer maintained in the future.
The CRD version of the operator is tested on the following platforms:
-
Kubernetes 1.7.X+
-
Kubernetes 1.8.0+
-
Openshift Origin 1.7.0+
This Operator has also been tested on the following operating systems:
-
CentOS 7
-
RHEL 7
To build and deploy the Operator on your Kubernetes system, follow the instructions documented on the Build and Install page.
With the operator deployed, the pgo command line interface can execute commands that the postgres-operator understands and reacts to.
The operator is template-driven; this makes it simple to configure both the client and the operator. The configuration options are documented on the Configuration page.
Some examples of using the pgo command line interface are as follows.
pgo show cluster all
pgo show cluster db1 db2 db3
pgo show cluster mycluster
pgo show cluster mycluster --show-secrets=truepgo create cluster myclusterpgo scale mycluster --replica-count=2pgo delete cluster myclusterpgo create backup myclusterpgo create cluster myrestore --secret-from=foo --backup-pvc=mypvc --backup-path=foo-backups/2017-03-21-15-57-21pgo create upgrade myclusterpgo create upgrade mycluster --upgrade-type=majorpgo show pvc mypvcpgo test myclusterpgo create policy policy1 --in-file=./policy1.sql
pgo create policy policy1 --url=https://someurl/policy1.sql|
Warning
|
Apply a Policy
policies are POWERFUL because they are executed as the superuser in PostgreSQL
which allows for any sort of SQL to be executed.
|
pgo apply policy1 --selector=name=myclusterDetails on the pgo commands and complex examples are found in the User Guide
#PostgreSQL Operator Container] == PostgreSQL Operator Container
In the following diagram, the PostgreSQL operator client, pgo, is shown interacting with the PostgreSQL operator that runs within a Kubernetes cluster. The operator is responsible for creating or modifying PostgreSQL databases deployed within the Kubernetes cluster.
The operator functionality runs in a Kubernetes Deployment on your Kubernetes cluster. The postgres-operator Docker container image is available on Dockerhub.
What actually gets created on the Kubernetes cluster for a pgcluster resource is defined as a deployment strategy. Strategies are documented in detail in Deployment Strategies.
You can also build the Docker image for postgres-operator using the build instructions located on the Build and Setup page.