A simple load balancer presence manager for Docker containers on top of etcd | Hacker News Reader

A simple load balancer presence manager for Docker containers on top of etcd

github.com

16 pointstegioz5 comments

I'm still waiting on a guide which can show how to host multiple public sites on a host server using Docker containers.

Do you need a load balancer which can send requests upstream based on host name? (Nginx load balancing perhaps?) is that not a good use case for docker?

Docker injects environment variables with ip addresses, as well as setting the host name. Hence it's very easy to use the environment variables and not worry about hostnames :-)

    backend beChalet
            option httpchk GET /
            server chalet ${CHALET_PORT_80_TCP_ADDR}:${CHALET_PORT_80_TCP_PORT} maxconn 200 check

https://docs.docker.com/userguide/dockerlinks/#container-lin... has more details

I wrote up a post with one way to do that: http://jasonwilder.com/blog/2014/03/25/automated-nginx-rever...

You can try nginx-proxy that wraps up the approach in a docker container. See https://registry.hub.docker.com/u/jwilder/nginx-proxy/.

Run that on your host and start your other containers on the host with VIRTUAL_HOST env variables and it will set up virtual host mappings via nginx automatically.

vulcand was designed to do this with etcd

https://github.com/mailgun/vulcand

Bonus points that via a trie, vulcand can scale in performance linearly to 10s of thousands (or more) of urls with 0 performance impact. (I requested that feature)

http://www.vulcanproxy.com/

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