Deploying Couchbase with Chef

This article by Keta Kiganal appears via Don Pinto.

If you are an administrator looking for an automated way to deploy Couchbase at scale, look no further - Chef is a great platform solution. Once setup, it is a very clean solution that can work across any number of physical, virtual, or cloud servers, no matter what the size of the infrastructure. Chef enables you to script your infrastructure deployment using code so that you can automate your provisioning and deployment process without much effort. 

In this blog, we will go over the chef recipes used to install couchbase, setup a cluster of couchbase nodes, add some buckets and finally add xdcr replication between clusters.

Before you start - Make sure you are familiar with the basics of chef server, cookbooks and chef-clients. Chef has a huge stack of templates, recipes, knife plugins which can be very useful to maintain large scale setups. http://wiki.opscode.com has good examples and information on this.

Setup a chef-server, workstation and have some nodes added on as chef-clients. Once the above 3 are setup, you are ready to write your Couchbase Cookbook. A forked version of the opscode cookbook is here https://github.com/ketakigangal/couchbase

Pre-requisites 
Install the following cookbooks before downloading the couchbase cookbook - yum, apt-get, windows, build-essential

Get the Couchbase cookbook
git clone  https://github.com/ketakigangal/couchbase

A quick look into the cookbook resources and available customizations
Based on your system needs, you can add more flexible attributes, resources, templates for the nodes and clusters. Ideally use the data-bags to define your cluster naming, here I have used role to describe very simple implementation of two clusters - “west_cluster” and “east_cluster”, more details ahead.

Attributes
The server.rb and client.rb have the default settings for server and clients. Make sure to reflect the needful couchbase versions, username/password for the server.rb in attributes. For example, the following installs a server 2.0.1-community edition -

default['couchbase']['server']['edition'] = "community"

default['couchbase']['server']['version'] = "2.0.1"

default['couchbase']['server']['username'] = "Administrator"

default['couchbase']['server']['password'] = "password"

Recipes

The server.rb and client.rb contain the logic for installing and setting up the Couchbase-Server and Clients respectively. Additionally the test_buckets.rb has sample code to create buckets and play around with the bucket settings.

The setup_cluster.rb can be used to setup a cluster, note this requires a role “west_cluster” ( say) to be assigned to each of the nodes of the cluster. Prerequisite to running this is to make sure each of the nodes have a couchbase server installed and started.

Similarly setup_xdcr.rb recipe is used to setup xdcr between two clusters. Prerequisite to using this is you already have 2 couchbase clusters setup  with roles “east_cluster” and “west_cluster”.

* Note : For this script to run, you must have nodes assigned with roles “east_cluster”, “west_cluster” for two separate clusters.

Libraries

The resources and providers are defined at a node, cluster, bucket level in this directory.

Upload the Cookbook using -

knife cookbook upload couchbase

Add recipes and roles to the node run_list using -

knife node run_list add fqdn-your-node-name "recipe[couchbase::server]"

knife node run_list add fqdn-your-node-name "recipe[couchbase::setup_cluster]"

knife node run_list add fqdn-your-node-name "recipe[couchbase::test_buckets]"

knife node run_list add role fqdn-your-node-name 'role[west_cluster]'

The above will add server, setup_cluster, test_bucket recipes for execution ( in that order) on the chef-client node. Here, we've assigned a role “west_cluster” to nodes to form a west_cluster.

knife show node fqdn-your-node-name

   “recipe[couchbase::server]",    

 "recipe[couchbase::setup_cluster]",

 "recipe[couchbase::test_buckets]",

 "role[west_cluster]"