azure-quickstart-templates/couchbase-ansible

Advanced Linux Template : Deploy a Multi VM Couchbase Cluster

This advanced template creates a Multi VM Couchbase Cluster,it also configures Ansible so you can easily manage all the VMS.

This template creates a new Storage Account (standard or premium) for all the Couchbase VMS , a Virtual Network, an Availability Sets (up to 3 Fault Domains and up to 20 Update Domains), one private NIC per VM, one public IP ,a Load Balancer.You can specify SSH keys to access your Ansible Controller remotely from your latop. Minimun recommded VM Size is Standard_D2 and by default 4 data disks will be attached to the VM. You will need an additional certificate / public key for the Ansible configuration and before executing the template you have to upload them to a Private azure storage account.

The template uses two Custom Scripts :

• The first script configures SSH keys (public) in all the VMs for the Root user so you can manage the VMS with ansible.
• The second script installs ansible on a A1 VM so you can use it as a controller.The script also deploys the provided certificate to /root/.ssh. Then, the script will execute an ansible playbook to create a RAID with all the available disks.
• Then, the script will install Couchbase in all the Servers using Ansible and the ansible-couchbase-server playbook.
• Before you execute the script, you will need to create a PRIVATE storage account and upload your certificate and public key that ansible will use, as well as the bash scripts and ansible Playbooks.

Once the template finishes, ssh into the AnsibleController VM (by default the load balancer has a NAT rule using the port 64000), then you can manage your VMS with ansible as the root user. For instance :

sudo su root
ansible all -m ping

Additionally, The Couchbase Web Admin Console will be exposed on the port indicated in the couchbaseWebConsolePort parameter. To expose the console securely, the Ansible Controller VM is configured as a nginx reverse proxy using https and self-signed certificates.

This template also ilustrates how to use Outputs and Tags.

• The template will generate an output with the fqdn of the new public IP so you can easily connect to the Ansible VM.
• The template will associate two tags to all the VMS : ServerRole (Webserver,database etc) and ServerEnvironment (DEV,PRE,INT, PRO etc)

Below are the parameters that the template expects

Name	Description
location	Region where you want to create all the resources
storageAccountName	Name of the storage account , the template will also append the name of the resource group
storageAccountType	Standard_LRS or Premium_LRS (For Premium, use the DS VMs)
imagePublisher	Canonica (default) or OpenLogic
imageOffer	"UbuntuServer" (default) or CentOS
imageSKU	"12.04.5-LTS" (default) or 6.5
vmNumberOfDataDisks	Number of Data Disk (* For future versions, today a fixed number of 4 disks will be created)
vmSizeDataDisks	Size of Data disks : By default 4 data disks will be created
vmFileSystem	ext4 or xfs (* For future versions)
createRAID	True or False. Specify true if you want to RAID all the data disks (* For future versions, currently if a RAID is created by default)
vmSize	Size of VMs, minimun size support Standard_D2
serversRole	Servers role, for instance webtier, database.A tag will be created with the provided value.
serversPurpose	Purpose of the server, for instance DEV, TEST, INT , PRO.A tag () will be created with the provided value .
numberOfVms	Number of VMS
adminUserName	Admin User Name
adminPassword	Admin Password
couchbaseAdminUser	Couchbase Admin User Name
couchbaseAdminPassword	Couchbase Admin User Password
couchbaseWebConsolePort	Couchbase Web Console Port
sshKeyData	SSH Key data
faultDomainCount	Number of Fault domains (Default 3, Maximum :3)
updateDomainCount	Number of Update domains (Default : 10 , Maximun : 20)
customScriptConfigStorageAccountName	Storage account name for the Private account that will contain your SSH Keys for ansible and the bash scripts ( Only use a Private storage account, as ssh keys should only be accesible by trusted users)
customScriptConfigStorageAccountKey	Storage account Key
sshRootCerBlobLocation	The Certificate for the ssh configuration used by ansible (You will need to upload your certificates / keys to the storage account before executing the template)
sshRootPubBlobLocation	The public key for the ssh configuration used by ansible (You will need to upload your keys to the storage account before executing the template)
virtualNetworkName	Virtual Network Name
dnsNameLabel	DNS Name that wil be associated to the Load balancer

##Known Issues and Limitations

• Fixed number of data disks : This is due to a current template limitation, this template creates 4 data disks with ReadOnly Caching.
• The Ansible Controller VM is configured as a reverse proxy for the Couchbase Admin Console,that it is exposed over https using the port 16195 and.Also, only the Ansible Controller is available for SSH using the port 6400.
• Current version uses self-signed certificates for the Couchbase Web Admin console, for production environments you should replace the self-signed certificates by your own certificates.
• Scripts are not yet idempotent and cannot handle updates (This currently works for create ONLY)