Here are the general requirements for a Container Host that is managed by Nirmata.

1. Can be any Linux flavor that can run Docker.
2. Requires Docker 1.10+ (see https://docs.docker.com/install/)
3. The Nirmata agent must be installed (see Using Cloud Init

Using cloud-init

If your OS provisioning system supports cloud-init, cloud-config, or similar initialization and provisioning mechanisms, you can easily install Docker and the Nirmata Agent as follows (assumes use of Direct Connect / Other Host Groups):

Ubuntu:

#!/bin/bash -x
# Install Docker
wget -qO- https://get.docker.com/ | sh

# Install Nirmata Agent
sudo curl -sSL https://www.nirmata.io/nirmata-host-agent/setup-nirmata-agent.sh | sudo sh -s -- --cloud other --hostgroup <key>

CentOS:

#!/bin/bash -x
# Install Docker
sudo yum update -y

sudo tee /etc/yum.repos.d/docker.repo <<-'EOF'
[dockerrepo]
name=Docker Repository
baseurl=https://yum.dockerproject.org/repo/main/centos/7/
enabled=1
gpgcheck=1
gpgkey=https://yum.dockerproject.org/gpg
EOF

sudo yum install -y docker-engine
sudo systemctl enable docker.service
sudo systemctl start docker

# Install Nirmata Agent
sudo curl -sSL https://www.nirmata.io/nirmata-host-agent/setup-nirmata-agent.sh | sudo sh -s -- --cloud other --hostgroup <key>

Amazon Linux:

#!/bin/bash -x
# Install docker
sudo yum update -y
sudo yum install -y docker
sudo service docker start  

# Install Nirmata Agent
sudo curl -sSL https://www.nirmata.io/nirmata-host-agent/setup-nirmata-agent.sh | sudo sh -s -- --cloud other --hostgroup <key>

Nirmata Agent Setup

To setup the Nirmata agent on the host instance

1. Run the Nirmata Agent configuration script:

   sudo curl -sSL https://www.nirmata.io/nirmata-host-agent/setup-nirmata-agent.sh | sudo sh -s -- --cloud <CloudProvider> --hostgroup <HostGroupId>
   
   where:
     CloudProvider = [aws | azure | vsphere | google | other]
     HostGroupId = unique ID for the Host Group. Only required for the 'Direct Connect' container hosts
   

2. Verify that Nirmata Agent has started:

   sudo docker ps
   

Note: Setup-nirmata-agent.sh uses upstart/systemd to enable management of nirmata-agent as a service. If upstart or systemd is not available on your host instance, you can directly run nirmata-agent container using docker.

To start/stop Nirmata agent you can use:

Upstart:

sudo start nirmata-agent
sudo stop nirmata-agent

Systemd:

systemctl start nirmata-agent
systemctl stop nirmata-agent

To setup the Nirmata agent on any host instance using commandline (for ‘other’ cloud provider):

docker run --rm -v /var/run/docker.sock:/var/run/docker.sock -v /var/log/nirmata-agent:/var/log/supervisor \
            -v /opt/nirmata/conf:/usr/share/nirmata/conf -v /opt/nirmata/db:/usr/share/nirmata/db --name=nirmata-agent \
            -v /sys:/sys:ro -e NIRMATA_HOST_ADDRESS=<HostName> -e NIRMATA_CLOUD_PROVIDER_TYPE=other -e NIRMATA_USE_HTTP=false\
            -e NIRMATA_HOST_GATEWAY=www.nirmata.io/host-gateway/manager -e NIRMATA_LABELS=<HostLabels> -e NIRMATA_HOST_GROUP_ID=<HostGroupId> nirmata/nirmata-agent:latest

where:
  HostName = Host name or IP address of your host
  HostGroupId = unique ID for the Host Group. Required for the 'other' cloud provider type
  HostLabels = Host labels in json format without any spaces between keys and values. e.g. NIRMATA_LABELS={"host-type":"SSD","host-location":"us-east"}

Host Labels

You can setup host labels when installing the Nirmata agent. Nirmata agent can detect host labels directly from Docker Engine. Host labels can also be passed in to Nirmata agent using environment variables.

Docker Engine:

Add the label option when start Docker Engine. Depending on your docker-engine installation, you can add the label option to DOCKER_OPTS
   e.g. --label environment-type="production"

Environment variable:

You can add the labels to Nirmata agent as environment variables. For this, you can modify the Nirmata agent init script (/etc/init/nirmata-agent.conf) and update the HOST_LABELS field. The labels should be specified in json format without any whitespaces.

e.g. HOST_LABELS={“host-type”:“SSD”,“host-location”:“us-east”}

Once you setup the host labels, you will need to restart the Nirmata agent. The host labels should be detected and display in Nirmata console once the host connects. Now, you can use these labels to control the placement of your containers.

HTTP Proxy

You can setup Nirmata agent to use a HTTP proxy to communicate to the internet. Here are the instructions.

Upstart:

Add the following to the docker run command in /etc/init/nirmata-agent.conf file:
    -e HTTPS_PROXY=<http(s) proxy address and port>

e.g. -e HTTPS_PROXY=https://192.162.11.11:443

Systemd:

Add the following to the docker run command in /opt/nirmata/bin/start-nirmata-agent.sh file:
    -e HTTPS_PROXY=<http(s) proxy address and port>

e.g. -e HTTPS_PROXY=https://192.162.11.11:443

Restart Nirmata agent using the appropriate command.

Host Networking

Nirmata does nor require any special networking setup, and works with your existing Host networking. Nirmata uses the Docker bridge network mode on each Host, so each application service is addressable using the Host IP address and an allocated (static or dynamic) port. Based on the cloud provider, Nirmata will detect the public and private IP addresses of your Host. When available, the Host’s private IP address will be used for communication between services.