footer: Javazone 2016 - 8. September 2016 slidenumbers: true

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#[fit] Terraform

colonise the cloud!

Stefan Magnus Landrø, BEKK Consulting

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Terraform

• Commandline tool (OS X, Windows, Linux, …)
• Developed by Hashicorp (Vagrant, Packer, Consul, Nomad)
• Lets you describe and provision cloud infrastructure using json-like text files
• Servers, networks, load balancing, storage
• Multi-provider (AWS, Azure, GC, Cloudstack, …)

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Demo

• Digital Ocean (Amsterdam, The Netherlands)
• 2 virtual machines (CentOS/Linux)
• Log in using public/private key
• Run Apache httpd web server
• Domain name (DNS) (AWS)
• Multi datacenter, multi provider, multi technology!

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Provider (1)

• A provider is used to connect to a cloud provider
• AWS, Azure, GC, Digital Ocean, Cloudstack, Openstack, Heroku, CloudFoundry, Mailgun, easyDNS, CloudFlare…
• Providers know the APIs and expose available services

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Resource (2)

• A resource defines how to use a cloud resource/service
  • VM, IP-address, load balancer, network, firewall, object storage, DNS-record
• The name of the provider is used as a resource name prefix
• Resources have unique ids
  • Combination of resource type and name

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Dependencies (3)

• A resource can depend on another resource
• Can determine the order of creation

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state og taint

• When manipulating resources, Terraform saves the current state i a .tfstate file (or S3, Atlas)

• Knows a resource's current state in the cloud

    terraform show
  

• When resources have to be recreated, it can be tainted

    terraform taint
  

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Syntax (4)

• Variables
• Interpolation
• Functions
  • base64, join, split, lower, upper, …

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Bonus: Domain Name Service

• Decentralised name system on the Internet
• A domain name can contain different types of records
• E.g.: www.vg.no
  • A: 195.88.55.16
  • A: 195.88.54.16
  • AAAA: 2001:67c:21e0::16

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Multi-provider (5)

• Can connect resources from different cloud providers
• Unique feature in Terraform!

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provisioner (6)

• A provisioner lets you provision against the resource right after creation
  • chef
  • remote-exec (script run on the server)
  • local-exec (script run locally)

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Bonus: floating IP (7)

• Floating IPs (Elastic IPs) are IP-adresses that can be moved between servers dynamically
• Prevent changing public IP in case of backend changes (no firewall issues)

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Let's go docker!

• Run docker containers on Elastic Container Service
• Virtual Private Cloud (VPC) (Security groups etc)
• Autoscaling group (Core OS)
• Container cluster
• Container Task/Service
• ALB Load Balancer

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Multi provider, multi datacenter, multi technology (8)

• DNS using weighted record set
  • Could have used latency / geolocation
• Health checks to determine data center (or service) outage

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Bonus: Dependency graph

• Dependency graphs can be generated dynamically

    terraform graph | dot -Tpng | open -f -a Preview
  

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Code

github.com/landro/terraform-do-ecs

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[fit]Q&A

_ @landro github.com/landro

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