CoreOS Fleet, link redundant Docker container -

i have small service split 3 docker containers. 1 backend, 1 frontend , small logging part. want start them using coreos , fleet.

i want try , start 3 redundant backend containers, frontend can switch between them, if 1 of them fails.

how link them? if use one, it's easy, give name, e.g. 'back' , link this

docker run  --name front --link back:back --link graphite:graphite -p 8080:8080 blurio/hystrixfront 

is possible link multiple ones?

the method dependent on type of backend service running. if backend service http there few proxy / load balancers choose from.

• nginx
• haproxy

the general idea behind these frontend service need introduced single entry point nginx or haproxy presents. tricky part this, or cloud service, need able introduce backend services, or remove them, , have them available proxy service. there writeups nginx , haproxy this. here one:

haproxy tutorial

the real problem here isn't automatic. there may techniques automatically introduce/remove backends these proxy servers.

kubernetes (which can run on top of coreos) has concept called 'services'. using deployment method can create 'service' , thing called 'replication controller' provides 'backend' docker process service describe. replication controller can instructed increase/decrease number of backend processes. frontend accesses 'service'. have been using , works quite well.

i realize isn't cut , paste answer. think question ask heart of cloud deployment.