Couchbase Ansible Playbook

This project contains sample playbooks to manage Couchbase NOSQL cluster.

🔗 Links

The current installation has been implemented based on

• Centos 7
• Couchbase version couchbase-server-enterprise-4.6.4-centos7.x86_64.rpm

Installation Pre-Requisties

• Three Virtual Machines installed with Centos 7
• From your Linux Control Machine(Your PC)
• Create ssh key and copy the public key to the three nodes
• Confirm access to all nodes
• Configure hostnames through your own DNS or /etc/hosts :

  * 192.168.35.157  cb-cluster.lab.example.com cb-cluster
  * 192.168.35.142  cb-node01.lab.example.com cb-node01
  * 192.168.35.139  cb-node02.lab.example.com cb-node02   

Couchbase Cluster Deployment

• Step 1 : Configure Ansible inventory file "inventory"

#This file contains 2 groups of couchbase server & couchbase nodes and ssh access variables
#select one of your server, this one will be used to initialize and configure the cluster
  [couchbase-main]
    cb-cluster.lab.example.com

#all other nodes that will be added to the cluster.
  [couchbase-nodes]
    cb-node01.lab.example.com
    cb-node02.lab.example.com

  [cb:children]
    couchbase-main
    couchbase-nodes

  [cb:vars]
    ansible_ssh_user="Your Own SSH User"
    ansible_become=true
    ansible_ssh_private_key_file="Path to Your Own SSH Private Key"
    ansible_ssh_common_args='-o StrictHostKeyChecking=no'

• Step 2 : Installing Cluster with Ansible Playbook roles
  • Enter the Administrator information and server configuration (RAM Quotas, Bucket name, Replicas) in the ./group_vars/all file or assign them directly from the role sections.
  • ansible-playbook -i inventory couchbase.yml -t "deploy,addnode"
• Step 3 : Access the cluster
  • from your browser : https://MainNodeHostname/IP:8091
  • login with cluster Username and Password

Ansible Role "deploy" Tasks :-

 * Install the required packages to prepare the couchbase server and nodes
 * Configure perfomance tuning on all cluster nodes :-
     1) nofile limits /etc/security/limits.conf
     2) vm.swappiness with sysctl
     3) disable Transparent Huge Pages :
       echo never > /sys/kernel/mm/transparent_hugepage/enabled
       echo never > /sys/kernel/mm/transparent_hugepage/defrag
  * Download the Couchbase package if not already present on all nodes
  * Install Couchbase on all nodes
  * Create a new cluster on the "main" node :
      -   cb-cluster.lab.example.com

Ansible Role "addnode" Tasks :_

   * Adding all other nodes to the cluster
   * listing the current cluster nodes
   * displaying couchbase cluster nodes
   * configuring couchbase cluster name
   * displaying cluster nodes information
   * Rebalancing the cluster after the added nodes registration
   * Creating a new bucket

Couchbase Cluster Uninstall

 -  Uninstall the Couchbase server and delete all files (Warning you will lose your data)
 -  ansible-playbook -i inventory couchbase.yml -t remove

Run Locally

Clone the project

  git clone https://github.com/mshgayar/couchbase.git

Go to the project directory

  cd couchbase

Update Invenotry file with the cluster hostnames

# vim inventory
 [couchbase-main]
 cb-cluster.lab.example.com

 [couchbase-nodes]
 cb-node01.lab.example.com
 cb-node02.lab.example.com

 [cb:children]
 couchbase-main
 couchbase-nodes

 [cb:vars]
 ansible_ssh_user=centos
 ansible_become=true
 ansible_ssh_private_key_file=~/.ssh/cloud-key
 ansible_ssh_common_args='-o StrictHostKeyChecking=no'

Update the global vars :

# vim group_vars/all

install the cluster with ansible playbook

  ansible-playbook -i inventory couchbase.yml -t "deploy,addnode"