Hello, dear DevOps Enquist, in this post I would like to discuss with you how to install Docker Enterprise Edition on CentOS 7 and plus Universal Control Plane (UCP) running to control the master and workers on three nodes(Virtualboxes). Amazed with the great features that incorporated into the UCP. You could do lot of things from your browser itself. In the last post I've explored about the swarm cluster that time I'd executed everything on CLI, but this time UCP Web UI.
Why we need a Docker Universal Control Plane(UCP)?
To make more production-ready setup we would do this experiment with three CentOS7 nodes. The following picture tells us how powerful UCP in Docker Enterprise Edition is. You can manage services, multiple deployments using stacks, summary and manage docker containers and their images. you can also add/remove nodes and get their status, category. Docker network full control on it. Storage volumes also you can manage from the UCP admin console.
- Ease of use with GUI based management
- High Availability(HA) made simple
- Access Control - organization, team, users manageable
- Monitoring - Overall system can be viewed in a single page
- docker native integration - network capabilities are handled
- Swarm Managed - Swarm master, worker nodes configured
- 3rd party plugins - DTR connects as plugin
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| Universal Control Plane running on Docker-ee with Swarm cluster |
Prerequisites for Docker EE installation
Infrastructure designing will be a crucial part of any environment that you build on the Cloud or on-premises Docker ecosystem. First, let's consider what all goes into the master node.
- Docker-EE installation (docker-ee) requires hub.docker.com signup and download the license
- Ports 80 and 443 are required to expose for UCP Containers to run.
- Docker Trusted Registry (DTR) only can run other than UCP running node because it also requires same reserved ports 80 and 443
- Download Vagrant as per your system
- Download VirtualBox
Here most importantly think about - what you run on a machine defines how much resources required.
How to install Docker-EE on CentOS 7?
It is a very interesting story,
Docker EE installation on CentOS 7 Vagrant boxes
1. Create three centos7 machines master - mstr, node1, node
2 for slaves.
2. Go to the hub.docker.com login with your credentials
The Vagrantfile content is as follows
Vagrant.configure(2) do |config|
config.vm.box = "centos/7"
config.vm.boot_timeout=600
config.landrush.enabled = true
config.vm.define "mstr" do |mstr|
mstr.vm.host_name = "mstr.devopshunter.com"
mstr.vm.network "private_network", ip: "192.168.33.100"
mstr.vm.provider "virtualbox" do |vb|
vb.cpus = "2"
vb.memory = "3070"
end
end
config.vm.define "node1" do |node1|
node1.vm.network "private_network", ip: "192.168.33.110"
node1.vm.hostname = "node1.devopshunter.com"
node1.vm.provider "virtualbox" do |vb|
vb.cpus = "2"
vb.memory = "1500"
end
end
config.vm.define "node2" do |node2|
node2.vm.network "private_network", ip: "192.168.33.120"
node2.vm.hostname = "node2.devopshunter.com"
node2.vm.provider "virtualbox" do |vb|
vb.cpus = "2"
vb.memory = "1500"
end
end
end
vagrant up
vagrant status
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| vagrant status for docker-ee installation on CentOS7 |
vagrant ssh-config
Use the PuTTYgen tool to convert the private_key to corresponding .ppk files. In my experiment, mstr.ppk, node1.ppk, node2.ppk files are generated in respective folders where private_key exists.
Now all set to go for connecting the each VM with corresponding IPs that assigned.
In each node you need to run the following commands:
1. Setup the repo for docker-ee
export DOCKERURL="https://storebits.docker.com/ee/centos/sub-eb111810-d6d8-4168-ac96-6e553a77381f"
sudo -E sh -c 'echo "$DOCKERURL/centos" > /etc/yum/vars/dockerurl'
cat /etc/yum/vars/dockerurl
2. Install docker dependdencies storage drivers
sudo yum install -y yum-utils device-mapper-persistent-data lvm2
3. Add the repo and tell that available at where (i.e., Path)
sudo -E yum-config-manager \
--add-repo \
"$DOCKERURL/centos/docker-ee.repo"
 |
| yum repo update for docker-ee |
4. Now all set to install the Docker enterprise edition
sudo yum -y install docker-ee
sudo systemctl start docker
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| docker-ee installation on CentOS7 completed! |
Now lets confirming by running hello-world container.
docker -v
sudo docker run hello-world
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| docker-ee installation confirmation with hello-world |
If we check the docker info on any node it looks like this.
 |
| docker info for the docker-ee |
Universal Control Plane (UCP) installation
docker container run --rm -it --name ucp \
-v /var/run/docker.sock:/var/run/docker.sock \
docker/ucp:2.2.5 install \
--host-address 192.168.33.100 \
--interactive
Enter username and password when it prompts.
admin
# welcome1
We detected the following hostnames/IP addresses for this system [mstr.devopshunter.com 127.0.0.1 172.17.0.1 192.168.33.100]
You may enter additional aliases (SANs) now or press enter to proceed with the above list.
Additional aliases:
INFO[0000] Initializing a new swarm at 192.168.33.100
INFO[0004] Establishing mutual Cluster Root CA with Swarm
This will automatically activate the swarm cluster master.
Login to UCP at https://192.168.33.100:443
UCP Login page
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| Universal Control Plane login page |
After clicking on Signin we will be prompted to use the 'upload license'. It will be available on your docker hub page from where you have got the docker-ee installation url. You can request for new trail license or else you can also go for skip for now option.
Here, I am loading that docker_subscription.lic file, which was already downloaded.
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| UCP Manager console |
Create a Swarm Node and join
Click on the Nodes, which will shows the a manager node already existing. Click on the 'Add Node' button.
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| UCP Configuring Nodes joining Swarm cluster |
The add node wizard page gives us choice to select node type 'Windows/Linux' and Node role as 'Manager' or 'Worker'. here we go with Linux node type and role as 'worker'
The highlighted bottom given docker swarm join command snippet copy the line, paster and run in the node1 and node2. This will take some time to join the swarm cluster. wait for a while and check the Cluster by refreshing.
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| Added nodes to Swarm cluster |
Initially when the nodes joined they have the status as 'Pending' and 'Awaiting', After join completed it looks 'Healthy UCP worker' status in the Details column.
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| Healthy UCP nodes |
I hope you enjoyed this post keep writing your valuable comments. Keep sharing with your techie friends who can appreciate you!
