RancherOS on QNAP

Long story short ...

In search of a Docker homelab environments which works on QNAP NAS, is quick to get up and running and requires minimal maintance during its lifecycle I have been going through different OS alternaternatives, for example Ubuntu, CentOS just to name two the most usual suspects. While using full blown Linux distros with all bells and whistles as a Docker host is a great as you get everything you need out of the box there is also cons side that I need to spend quite some time to provisioning a host (or node or VM whichever you may want to call it) before a it is actually usable. This is likely to change in future after I have done with my experiments using 'cloud-init' to provision new hosts.

So I decided to look alternatives, namely Container Operating systems e.g. CoreOS (Red Hat), Photon OS (VMware), RancherOS (Rancher Labs), to name few, and decided to give RancherOS try as it looked fairy straight forward to setup and as I am planning to deep dive Rancher ecosystem more deeply in future. So far outcome is so promising. I have now few RancherOS based Docker node VMs up and running. With 'cloud-config' set of a new node is breeze with minimal amount of manual work and Docker is up and running out of the box. As cons side RancherOS is really bare minimal so I am lacking many Linux tools and from Docker perspective a biggest gap is lack of 'docker-compose' which Rancher Labs has replaced with their own version, called 'rancher-compose'. I have not yet tried 'rancher-compose' myself as I need to figure out how to get it installed first.

Regarless, I am planning to run with RancherOS for timebeing for my homelabs as pros quickly getting new nodes running and minimal OS maintenance weights more at this stage. Below are instructions how I got RancherOS up and running on my QNAP NAS.

Pre-installation steps

These steps are only needed to be executed once (as longs as you store/document outcome).

Download an RancherOS image from (I am currently using rancheros.iso)

https://github.com/rancher/os/blob/master/README.md

Generate SSH keypair for a remote SSH access from your client machine into RancherOS VM and note your public key (you need it for cloud-config.yaml). In your SSH client machine execute following steps.

client$ ssh-keygen
client$ cat $HOME/.ssh/id_rsa.pub

Generate Docker Hub access token to able to push dokcer images to Hub

- In your Docker Hub profile view click 'Edit profile'-> 'Security'
- Click 'New Access Token' to create a new access token.
- Note a token for later use (you need it for cloud-config.yaml)

Create cloud-config.yaml

This is an example 'cloud-config.yaml' (created in my client machine). You need to create a unique yaml-file for each node you provision.

# cloud-config
hostname: docker-ce
ssh_authorized_keys:
  - <place your id_rsa.pub content here>
# Optional, in case you need access external filesystems inside of your RancherOS node.
mounts:
  - ["<nfs-server-ip>:/rancheros", "/storage", "nfs4", ""]
rancher:
  # enable VM tools and NFS client functionality
  services_include:
    qemu-guest-agent: true
    volume-nfs: true
  network:
    interfaces:
      eth0:
        dhcp: false
        address: 192.168.51.10/24
        gateway: 192.168.51.254
    dns:
      nameservers:
        - 1.1.1.1
        - 1.0.0.1
      override: true
    # auth is base64 from your docker hub user id and access token you created earlier using format 'username:token'
    registry_auths:
      https://index.docker.io/v1/:
        auth: <place base64 from 'username:token' here>

Create a new persistant RancherOS node VM

Create VM by using QNAP Virtualization Station. These steps are needed for every node you create with an unique 'cloud-config.yaml' you have created in above step from above example.In 'Create VM' window I use following settings.
Note: Boot from ISO image (earlier downloaded rancheros.iso) requires minimal 2048MB to boot up. After installation is fully completed you are able to adjust memory, I am running some of nodes with 1024 MB memory.

- OS type: Generic
- Memory: 2048 MB (note: with 1024 MB) VM will not boot up)
- CD image: rancheros.iso
- HDD storage: 8 GB
- Network -> Connect to: <choose one of networks you have available in drop down menu>

After RancherOS VM is up and running, connect it with Virtualization Station console and print IP address of VM

$ ip address

Set 'rancher' user password. RancherOS normally does not use password based authentication and strongly recommends to use SSH key based login but this step is needed to transfer 'cloud-config.yaml' into VM.

$ sudo password rancher

Transfer 'cloud-config.yaml into VM from your client machine.

client$ sftp rancher@<vm-ip-address>
> put cloud-config.yaml
> exit

client$ ssh -l rancher <vm-ip-address>

Install RancherOS to a disk (for persistant installation) in order of RancherOS to able to store its state to dick.

$ sudo ros install -c cloud-config.yaml -d /dev/sda
Note: Press 'y' to confirm installation step

DO NOT REBOOT when you get a promt "Continue with reboot [y/N]:' instead execute following steps from Virtualization station

- Shutdoewn VM
- Remove mount to 'rancheros.iso'from VM (click 'Eject CD image at CD/DVD configuration section)
- Start VM

After VM was started, test your installation

# login into VM with SSH
client$ ssh -l rancher <vm-ip-address>
# Check that docker is running
$ docker version
# Check that NFS mount was successful (you should see content of 'rancheros' directory within external system)
$ ls -al /storage

- In Virtualization Station check that IP address of VM is visible under 'Network' section when you browse VM 'Information' section

Note about console access:
As default you will not be able to login via console into RancherOS vM. If you need console access into a RancherOS node VM, on VM console screen select 'Autologin on tty1 amd ttyS0' bootloader option to enable 'rancher' user autologin.

Note about multiple network interfaces:
If you define multiple network interface in 'cloud-config.yaml' you also need to provision equal amount of interfaces that sits on same network for VM by using Virtualization Station. You may do that in following way

- Select VM
- Goto VM 'Settings'
- Clich 'Add device' button on top right corner
- Choose 'Network' device type
- Select network you want to attach interface from 'Virtual switch' drop down menu
- Choose device model (I use 'Intel Gigabit Ethernet' myself)
- Click 'Apply' on bottom right corner

References:

TO-DO:

Docker Hub login with token does not work, will be fixed later stage. As workaround login manually with 'docker login'
How to deploy 'rancher-compose', equalent to 'docker-compose' on Rancher ecosystem up and running