Introduction to Consul

In this talk we briefly introduce Consul and how it solves core problems for a Service Oriented Architecture (SOA) of service discovery, load balancing, health checking and configuration.

1. Introduction to Consul
2. I’m Armon Dadgar @armon
3. HashiCorp A DevOps tools company
5. SOA Primer • Service Oriented Architecture • Autonomous • Limited Scope • Loose Coupling • e.g. opposite of classic monolith
6. Web App Forecasting Order Processing Order History
7. Web App Order Processing Discovery Which nodes are part of “Order Processing”?
8. Web App Order Processing Node 1 Node N … Load Balancing How to ensure request leveling across providers?
9. Web App Order Processing Node 1 Node N … Load Balancer Anti-Pattern! Load Balancer is a Single Point of Failure (SPOF)
10. Web App Order Processing Node 1 Node N … Health Checking How to avoid routing to unhealthy hosts?
11. Web App Web App Web App Maintenance = true EnableFeature = false Configuration How to efficiently push dynamic configuration?
12. Recap • Service Discovery • Load Balancing • Health Checking • Configuration
13. Problems? Check.
14. Solutions? Nope.
15. Solutions* • ZooKeeper, etcd, doozerd • Nagios, Sensu • SkyDNS • SmartStack Consul Comparisons: http://www.consul.io/intro/vs/index.html
16. Build it yourself!
17. First Pass: Serf • Node membership • Failure Detection • Custom Events • Tag Meta Data • http://serfdom.io
18. Serf Shortcomings • 1 Node : 1 Service • 1 : N possible with tag overloading • Liveness check only • Fully decentralized • Joy to operate • Difficult to extend • Eventually Consistent Only
19. Learning • 1 Node : N Services • Host checks + Service Checks • Simpler interfaces (Serf only MsgPack/TCP) • Strong Consistency • Multi Datacenter (Serf WAN not optimal)
20. Consul
21. Service Discovery HTTP + DNS Datacenter Aware (Ritualistic sacrifice not required) K/V Store HTTP API Host & Service Level Health Checks
22. It Just Works.
24. Consul Today • Powers Vagrant Cloud • Used in our on-premise product • Version 0.1 Released • Version 0.2 Next Week • Web UI
25. Consul Tomorrow • Partner Deploys • Version 0.3+ • Leader Election • Clients • CLI tools
26. Thanks! http://consul.io