Have you wondered what the best way is to quickly list which instances are available in an AWS region? When the t2.nano was added to the Sydney region this week, I thought exactly this.

First place you would look would be the pricing page and select your region. However this only lists the latest instance types, you have to click through to another page to see the older generations. As a technical person you think "surely this can be done from the CLI"?

First port of call would be the trusty AWS CLI which I just love, its so handy. However there is no command which lets you extract the instances types. The closest you can get is to list the currently available reserved instances, for example

aws ec2 describe-reserved-instances-offerings --query "ReservedInstancesOfferings[?AvailabilityZone=='ap-southeast-2a'] [InstanceType]" --output text --region "ap-southeast-2" | sort -u

Problem with this command is that there may be an instance type which does not have an RI available. When I was doing this t2.nano and hi1.4xlarge were not available for RI in Sydney. So the CLI is probably not the best solution here.

The only other possibility is the relatively new pricing file. This was created to provide a programatic interface to the pricing data instead of the nasty scraping hacks people previously performed. The pricing file for EC2 lists all of the instances available and looks something like this.

{
  "formatVersion" : "v1.0",
  "disclaimer" : "This pricing list [...]",
  "offerCode" : "AmazonEC2",
  "version" : "20160126001708",
  "publicationDate" : "2016-01-26T00:17:08Z",
  "products" : {
    "DQ578CGN99KG6ECF" : {
      "sku" : "DQ578CGN99KG6ECF",
      "productFamily" : "Compute Instance",
      "attributes" : {
        "servicecode" : "AmazonEC2",
        "location" : "US East (N. Virginia)",
        "locationType" : "AWS Region",
        "instanceType" : "hs1.8xlarge",
        "currentGeneration" : "No",
        "instanceFamily" : "Storage optimized",
        "vcpu" : "17",
        "physicalProcessor" : "Intel Xeon E5-2650",
        "clockSpeed" : "2 GHz",
        "memory" : "117 GiB",
        "storage" : "24 x 2000",
        "networkPerformance" : "10 Gigabit",
        "processorArchitecture" : "64-bit",
        "tenancy" : "Shared",
        "operatingSystem" : "Windows",
        "licenseModel" : "License Included",
        "usagetype" : "BoxUsage:hs1.8xlarge",
        "operation" : "RunInstances:0002",
        "preInstalledSw" : "NA"
      }
    },

P.S. Thanks to the Solution Architects in the Sydney team at AWS who thought of using describe-reserved-instances-offerings in the CLI, turns out it is not as fruitful as the pricing file though.