Trilha Containers How we figured out we had a SRE team at - Traefik: Dynamic container load balancer for containers

1. Traefik: Dynamic Load Balancer For Containers
Marcelo Pinheiro
@salizzar

3. $ whoami
• Fireman / Problem Solver /
Programmer since 2000
• Ruby, Python, Golang, Java, C#,
Classic ASP, PHP, Node.js, Erlang
and others
• Fought, made coffee, negotiated
deadlines
• DevOps Engineer @ Work & Co

4. Load Balancing For Microservices
A brief introduction.

5. Load Balancing For Microservices
• Load balancing: a technique to
equally distribute traffic between
servers (duh.)
• Most popular options runs on Layer 4
or Layer 7 (OSI: Open Systems
Interconnection Model)
• Layer 4: operates at the
intermediate transport layer (TCP/
IP)
• Layer 7: operates at the high-level
application layer (user namespace)

6. Load Balancing For Microservices
• L4 options:
• LVM
• L7 options:
• NGINX
• Apache HTTP Server
• HAProxy
• Most public / private clouds have
their solutions inside-the-box

7. Load Balancing For Microservices
• In a microservices environment where
one service runs in one instance as a
standard and scaling is manual, L4 / L7
load balancing options are good enough
• And about containers?
• AWS ELB supports ECS
• Microsoft Azure supports ACS (but
requires DC/OS)
• GCE uses GKE
• OpenStack uses neutron-lbaas

8. Traditional HTTP Servers and Containers:
A not-so-simple path.

9. Traditional HTTP Servers and Containers
• HAProxy, Apache HTTP Server and
NGINX are created before of
Microservices / Containers boom
• Based on static vhost
configuration
• You need to previously know the
number of upstreams to configure
• But how to dynamically discover
new servers / containers and
discard old ones?

10. Traditional HTTP Servers and Containers
• A solution: Service Discovery
• Automate discover of new servers /
containers in a cluster
• A very good explanation: https://
www.nginx.com/blog/service-discovery-
in-a-microservices-architecture/
• Available options:
• Consul
• etcd
• Apache ZooKeeper

11. Traditional HTTP Servers and Containers
• Most famous solution to Apache
HTTPD, NGINX and HAProxy:
consul-template
• Uses Consul as service registry
database to discover new
instances / containers running
• Dynamically generate vhost files
and sends a SIGHUP signal to
nginx / httpd daemon reload
configurations and apply changes
(hot-reload)

12. Traditional HTTP Servers and Containers
• It works? Yes.
• But you need to create a Consul
infrastructure
• A Consul master
• Pool of Consul agents
• Dockerized Consul isn’t a good
idea
• Obviously, more one dependency

13. Traefik: Dynamic Load Balancer For Containers
Cheese As A Service.

14. Traefik: Dynamic Load Balancing For Containers
• Created by Emile Vauge
• Written in Go
• Focused on microservices
• HTTP/2 Support
• Websockets
• Let’s Encrypt
• Docker, Swarm, Kubernetes, Marathon,
Mesos, Consul, Etcd and others

15. Traefik: Dynamic Load Balancing For Containers
• How it works?
• Traefik listens to backend /
orchestrator API’s and detects any
changes, applying it
• Routes are dynamically managed
• You can create / update / destroy
routes at any time

16. Traefik: Dynamic Load Balancing For Containers
• How it works internally?
• Traefik reads service metadata on
Docker / Kubernetes / etcd / etc
• Hosts, ports, load balancing
algorithm etc
• You can persist configuration
using Consul, BoltDB, Amazon
ECS and other backends
• Let’s Encrypt integration
requires a key-value storage

17. Traefik: Dynamic Load Balancing For Containers
• Traefik main concepts:
• Entrypoints: network entry points
(HTTP, HTTPS, SSL etc)
• Backends: a load-balancing
method to receive requests
• Frontends: set of rules that maps
entrypoints to backends

18. Yes.
Live Demo time! Running in a Docker Swarm cluster.

19. Questions? Is free.
About benchmarks, visit https://docs.traefik.io/benchmarks/

20. Thank you! :)