docker-swarm-mode

I'm working on a project to set up a cloud architecture using docker-swarm. I know that with swarm I could deploy replicas of a service which means multiple containers of that image will be running to serve requests. I also read that docker has an internal load balancer that manages this request distribution. However, I need help in understanding the following: Say I have a container that exposes a service as a REST API or say its a web app. And If I have multiple containers (replicas) deployed in the swarm and I have other containers (running some apps) that talk to this HTTP/REST service.

I have a compose file with v3 where there are 3 services sharing/using the same volume. While using swarm mode we need to create extra containers & volumes to manage our services across the cluster. I am planning to use NFS server so that single NFS share will get mounted directly on all the hosts within the cluster. I have found below two ways of doing it but it needs extra steps to be performed on the docker host - Mount the NFS share using "fstab" or "mount" command on the host & then use it as a host volume for docker services. Use Netshare plugin - https://github.com/ContainX/docker

I cannot connect to external mongodb server from my docker swarm cluster. As I understand this is because of cluster uses overlay network driver. Am I right? If not, how does docker overlay driver works and how can I connect to external mongodb server from cluster? François Maturel Q. How does the docker overlay driver work? I would recommend this good reference for understanding docker swarm network overlay, and more globally, Docker's architecture . This states that: Docker uses embedded DNS to provide service discovery for containers running on a single Docker Engine and tasks running in a