Setup process for Azure Discovery

We will expose here one strategy which is to hide our Elasticsearch cluster from outside.

With this strategy, only VMs behind the same virtual port can talk to each other. That means that with this mode, you can use Elasticsearch unicast discovery to build a cluster, using the Azure API to retrieve information about your nodes.

Prerequisites

edit

Before starting, you need to have:

A Windows Azure account
OpenSSL that isn’t from MacPorts, specifically OpenSSL 1.0.1f 6 Jan 2014 doesn’t seem to create a valid keypair for ssh. FWIW, OpenSSL 1.0.1c 10 May 2012 on Ubuntu 14.04 LTS is known to work.
SSH keys and certificate

You should follow this guide to learn how to create or use existing SSH keys. If you have already did it, you can skip the following.

Here is a description on how to generate SSH keys using openssl:
```
# You may want to use another dir than /tmp
cd /tmp
openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout azure-private.key -out azure-certificate.pem
chmod 600 azure-private.key azure-certificate.pem
openssl x509 -outform der -in azure-certificate.pem -out azure-certificate.cer
```
Generate a keystore which will be used by the plugin to authenticate with a certificate all Azure API calls.
```
# Generate a keystore (azurekeystore.pkcs12)
# Transform private key to PEM format
openssl pkcs8 -topk8 -nocrypt -in azure-private.key -inform PEM -out azure-pk.pem -outform PEM
# Transform certificate to PEM format
openssl x509 -inform der -in azure-certificate.cer -out azure-cert.pem
cat azure-cert.pem azure-pk.pem > azure.pem.txt
# You MUST enter a password!
openssl pkcs12 -export -in azure.pem.txt -out azurekeystore.pkcs12 -name azure -noiter -nomaciter
```
Upload the azure-certificate.cer file both in the Elasticsearch Cloud Service (under Manage Certificates), and under Settings -> Manage Certificates.

When prompted for a password, you need to enter a non empty one.

See this guide for more details about how to create keys for Azure.

Once done, you need to upload your certificate in Azure:
- Go to the management console.
- Sign in using your account.
- Click on Portal.
- Go to Settings (bottom of the left list)
- On the bottom bar, click on Upload and upload your azure-certificate.cer file.
You may want to use Windows Azure Command-Line Tool:
Install NodeJS, for example using homebrew on MacOS X:
```
brew install node
```
Install Azure tools
```
sudo npm install azure-cli -g
```

Download and import your azure settings:

# This will open a browser and will download a .publishsettings file
azure account download

# Import this file (we have downloaded it to /tmp)
# Note, it will create needed files in ~/.azure. You can remove azure.publishsettings when done.
azure account import /tmp/azure.publishsettings

Creating your first instance

edit

You need to have a storage account available. Check Azure Blob Storage documentation for more information.

You will need to choose the operating system you want to run on. To get a list of official available images, run:

azure vm image list

Let’s say we are going to deploy an Ubuntu image on an extra small instance in West Europe:

Azure cluster name	`azure-elasticsearch-cluster`
Image	`b39f27a8b8c64d52b05eac6a62ebad85__Ubuntu-13_10-amd64-server-20130808-alpha3-en-us-30GB`
VM Name	`myesnode1`
VM Size	`extrasmall`
Location	`West Europe`
Login	`elasticsearch`
Password	`password1234!!`

Using command line:

azure vm create azure-elasticsearch-cluster \
                b39f27a8b8c64d52b05eac6a62ebad85__Ubuntu-13_10-amd64-server-20130808-alpha3-en-us-30GB \
                --vm-name myesnode1 \
                --location "West Europe" \
                --vm-size extrasmall \
                --ssh 22 \
                --ssh-cert /tmp/azure-certificate.pem \
                elasticsearch password1234\!\!

You should see something like:

info:    Executing command vm create
+ Looking up image
+ Looking up cloud service
+ Creating cloud service
+ Retrieving storage accounts
+ Configuring certificate
+ Creating VM
info:    vm create command OK

Now, your first instance is started.

Working with SSH

You need to give the private key and username each time you log on your instance:

ssh -i ~/.ssh/azure-private.key [email protected]

But you can also define it once in ~/.ssh/config file:

Host *.cloudapp.net
 User elasticsearch
 StrictHostKeyChecking no
 UserKnownHostsFile=/dev/null
 IdentityFile ~/.ssh/azure-private.key

Next, you need to install Elasticsearch on your new instance. First, copy your keystore to the instance, then connect to the instance using SSH:

scp /tmp/azurekeystore.pkcs12 azure-elasticsearch-cluster.cloudapp.net:/home/elasticsearch
ssh azure-elasticsearch-cluster.cloudapp.net

Once connected, install Elasticsearch:

Check that Elasticsearch is running:

GET /

This command should give you a JSON result:

{
  "name" : "Cp8oag6",
  "cluster_name" : "elasticsearch",
  "cluster_uuid" : "AT69_T_DTp-1qgIJlatQqA",
  "version" : {
    "number" : "7.17.26",
    "build_flavor" : "default",
    "build_type" : "tar",
    "build_hash" : "f27399d",
    "build_date" : "2016-03-30T09:51:41.449Z",
    "build_snapshot" : false,
    "lucene_version" : "8.11.3",
    "minimum_wire_compatibility_version" : "1.2.3",
    "minimum_index_compatibility_version" : "1.2.3"
  },
  "tagline" : "You Know, for Search"
}

Install Elasticsearch cloud azure plugin

edit

# Stop Elasticsearch
sudo service elasticsearch stop

# Install the plugin
sudo /usr/share/elasticsearch/bin/elasticsearch-plugin install discovery-azure-classic

# Configure it
sudo vi /etc/elasticsearch/elasticsearch.yml

And add the following lines:

# If you don't remember your account id, you may get it with `azure account list`
cloud:
    azure:
        management:
             subscription.id: your_azure_subscription_id
             cloud.service.name: your_azure_cloud_service_name
             keystore:
                   path: /home/elasticsearch/azurekeystore.pkcs12
                   password: your_password_for_keystore

discovery:
    type: azure

# Recommended (warning: non durable disk)
# path.data: /mnt/resource/elasticsearch/data

Restart Elasticsearch:

sudo service elasticsearch start

If anything goes wrong, check your logs in /var/log/elasticsearch.

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