DOCKER SWARM Install HYPER-V

1. Create Workers machines

   • For windows :
     • SET UP A NEW EXTERNAL NETWORK SWITCH : [LINK]
     • Docker machine creation
       • docker-machine create -d hyperv --hyperv-virtual-switch "Primary Virtual Switch" worker1

2. Create Leader SWARM machine:

   • Create

     • docker-machine create -d hyperv --hyperv-virtual-switch "Primary Virtual Switch" leader1

   • Init swarm

     • docker-machine ssh
     • ip addr show (for getting the right IP address)
     • docker swarm init --advertise-addr=10.0.52.83

3. Join machines workers to SWARM

   • SSH Connection to machines
     • docker-machine ssh worker1
     • docker swarm join --token SWMTKN-1-1lbtkl0ga7puka3vs9gn489lvf991k4iij72jz3jvanrkgnxok-3b7r8m8afewuomyhiej4rf8do 10.0.52.83:2377
   • Command for leaving a swarm :
   • docker swarm leave --force
   • Display nodes
     • docker node ls

4. Install docker-swarm-visualizer

   • docker service create --name=visualizer --publish=8080:8080/tcp --constraint=node.role==manager --mount=type=bind,src=/var/run/docker.sock,dst=/var/run/docker.sock dockersamples/visualizer

5. Create an overlay network

   • Network:
     • docker network ls
   • Command:
     • docker network create --driver overlay my-network
   • Network inspection
     • docker network inspect my-network

6. Install services on swarm mode:

   • Services list:
     • docker service ls
     • Install new service (ex: une image alpine ):
       • docker service create --replicas 1 --name helloworld alpine ping docker.com

7. Scaling

8. Docker Stack commands:

   • Deploy:
     • docker stack deploy --compose-file docker-compose.yml stackName
   • Services list:
     • docker stack services stackName
   • Bring the stack down:
     • docker stack rm stackName
   • Bring the registry down:
     • docker stack rm registry
   • Bring the docker Engine out of swarm mode
     • docker swarm leave --force

Various

Certif problem and ssh unavailable

rm -R ~/.docker docker-machine --debug regenerate-certs -f worker1

Machine environment

docker-machine env worker3

Getting the token to join swarm command

docker swarm join-token worker

A FAIRE : es + docker beat + Consul

LINK

Service discovery CONSUL

Swarm consul Traeffic

ERRORS : This machine has been allocated an IP address, but Docker Machine could not reach it successfully. SSH for the machine should still work, but connecting to exposed ports, such as the Docker daemon port

• sudo ifconfig vboxnet0 down && sudo ifconfig vboxnet0 up

Before Docker 1.12, setting up and deploying a cluster of Docker hosts required you to use an external key-value store like etcd or Consul for service discovery. With Docker 1.12, however, an external discovery service is no longer necessary, since Docker comes with an in-memory key-value store that works out of the box

Docker Networking

Add a host without a driver

You can register an already existing docker host by passing the daemon url. With that, you can have the same workflow as on a host provisioned by docker-machine.

$ docker-machine create --driver none --url=tcp://50.134.234.20:2376 custombox

An overlay network without swarm mode

If you are not using Docker Engine in swarm mode, the overlay network requires a valid key-value store service. Supported key-value stores include Consul, Etcd, and ZooKeeper (Distributed store). Before creating a network in this way, you must install and configure your chosen key-value store service.

Embedded DNS server

Docker daemon runs an embedded DNS server which provides DNS resolution among containers connected to the same user-defined network, so that these containers can resolve container names to IP addresses. If the embedded DNS server is unable to resolve the request, it is forwarded to any external DNS servers configured for the container.

Each Docker engine runs an embedded DNS server, which can be queried by processes running in containers on a specific Docker host, provided that the containers are attached to user-defined networks (i.e. Note: not the default bridge network, called bridge). Container and Swarm service names can be resolved using the embedded DNS server, provided the query comes from a container attached to the same network as the container or service being looked up

In our scenario, we can use the service name, nginx, instead of the virtual IP address, to consume the service. The name will be resolved to the virtual IP address, and the service request will be routed to one of the task containers running in the cluster.

Docker and iptables

Linux hosts use a kernel module called iptables to manage access to network devices, including routing, port forwarding, network address translation (NAT), and other concerns. Docker modifies iptables rules when you start or stop containers which publish ports, when you create or modify networks or attach containers to them, or for other network-related operations.

Virtual IP address

Now, if another service or discrete container wanted to consume the nginx service, how will it address the service?

Swarm has this covered, and allocates each service that gets created a virtual IP address through which it can be addressed. If we inspect the nginx service, we can see the virtual IP address:

$ docker service inspect --format '{{json .Endpoint.VirtualIPs}}' nginx | jq '.'
[
  {
    "NetworkID": "4pnw0biwjbns0bjg4ey6cepri",
    "Addr": "192.168.35.2/24"
  }
]

Container communication between hosts

For security reasons, Docker configures the iptables rules to prevent containers from forwarding traffic from outside the host machine, on Linux hosts. Docker sets the default policy of the FORWARD chain to DROP.

Weave Net network driver

Weave Net creates a virtual network that connects Docker containers across multiple hosts and enables their automatic discovery. With Weave Net, portable microservices-based applications consisting of multiple containers can run anywhere: on one host, multiple hosts or even across cloud providers and data centers. overview

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NOTE La communication inter-services doit être faite par les ip virtuelles

Tech Stack Objectif "# synker-docker"