PostgreSQL Slave

Introduction

This stack creates PostgreSQL Slave Database using GitOps. Before you use this stack, make sure you have a PostgreSQL Master Database is up and running.

Stack Code

  • Postgres_slave-12.2 - To be mentioned in build.image_template in appz.yml. See Sample AppZ Yaml.

Pre-requisites

Before deploying Postgres Slave, make sure both the [Vault]{https://github.com/ecloudcontrol/Vault] and [postgres-master]{https://github.com/ecloudcontrol/postgres-master} applications are deployed.

Sample Project

Postgres Slave - Optionally use this sample project to deploy PostgreSQL Slave database. Before running this, make sure master database is up and running.

Sample AppZ YAML

If you fork Postgres Slave , you will see the following appz.yml in the root of the project. 

app:
    name: Postgres Slave
    code: POSTGRESSLAVE
    notify: appzdev@cloudbourne.co

build:
    version: 12.2
    env: DEV
    build_file: none
    output_files: output/*.zip
    image_template: postgres_slave-12.2
    image_name: alpha/postgres_slave

deploy:
    context: alpha/DEV
    type: statefulset
    replicas: 1
    port:
    - 5432

volumes:
  - claim: postgres-slave-data
    mount: /appz/data
    name: data
    size: 5Gi
    mode: ReadWriteOnce
    class: microk8s-hostpath    

monitor:
    notify: appzops@cloudbourne.co      

properties:
    POSTGRESQL_REPLICATION_MODE: slave
    POSTGRESQL_DATA: /appz/data
    POSTGRESQL_CONNECTUSER: postgres
    POSTGRESQL_PASSWORD: 
      vault: POSTGRESQL_PASSWORD
    POSTGRESQL_REP_USER: replica    
    PGPASSWORD: 
      vault: PGPASSWORD 
    POSTGRESQL_MASTER_HOST: postgres-master-12-2
    POSTGRESQL_PORT: 5432    
    revision : 25

See below the explanation of appz.yml which user can customize.

Properties

The image is vault enabled so secrets can be pulled from vault. These are placed under properties in appz.yml. Please check each one below, with its actual purpose.

  • POSTGRESQL_REPLICATION_MODE - Server replication mode (master/slave)
  • POSTGRESQL_DATA - Data storage location
  • POSTGRESQL_CONNECTUSER - The default user 'postgres' in the PostgreSQL server
  • POSTGRESQL_PASSWORD - Password of the user 'postgres', enter this into AppZ Vault
  • POSTGRESQL_REP_USER - Replication user to sync from Master to Slave
  • PGPASSWORD - Replication user password, enter this into AppZ Vault
  • POSTGRESQL_MASTER_HOST - The Master PostgreSQL server
  • POSTGRESQL_PORT - Default port for PostgreSQL
  • revision - A dummy property to help trigger GitOps

Volumes

It is stateful deployment and volumes are created for /appz/data as per volumes: section in appz.yml

Standard AppZ Volumes is also enabled.