11.02.2018

Docker-Machine: how to create a docker vm on a remote virtualbox server

After doing some first steps with docker, i wanted to test docker-swarm. Because of the limited resources of my notebook, i was looking for a Linux with a minimal footprint. In the context of setting up VMs for docker-swarm i found a log of articles about doing that with the tool docker-machine.
It sounds like this tool can create VMs just with one command. (here the documentation).

So let's give it a try:
(You have to install docker-machine first, but you do not need to install docker itself)
~$ docker-machine create --driver virtualbox test
Creating CA: /home/schroff/.docker/machine/certs/ca.pem
Creating client certificate: /home/schroff/.docker/machine/certs/cert.pem
Running pre-create checks...
(test) Image cache directory does not exist, creating it at /home/schroff/.docker/machine/cache...
(test) No default Boot2Docker ISO found locally, downloading the latest release...
(test) Latest release for github.com/boot2docker/boot2docker is v17.11.0-ce
(test) Downloading /home/schroff/.docker/machine/cache/boot2docker.iso from https://github.com/boot2docker/boot2docker/releases/download/v17.11.0-ce/boot2docker.iso...
(test) 0%....10%....20%....30%....40%....50%....60%....70%....80%....90%....100%
Creating machine...
(test) Copying /home/schroff/.docker/machine/cache/boot2docker.iso to /home/schroff/.docker/machine/machines/test/boot2docker.iso...
(test) Creating VirtualBox VM...
(test) Creating SSH key...
(test) Starting the VM...
(test) Check network to re-create if needed...
(test) Found a new host-only adapter: "vboxnet0"
(test) Waiting for an IP...
Waiting for machine to be running, this may take a few minutes...
Detecting operating system of created instance...
Waiting for SSH to be available...
Detecting the provisioner...
Provisioning with boot2docker...
Copying certs to the local machine directory...
Copying certs to the remote machine...
Setting Docker configuration on the remote daemon...
Checking connection to Docker...
Docker is up and running!
To see how to connect your Docker Client to the Docker Engine running on this virtual machine, run: docker-machine env test
Wow.
After this command inside my virtualbox a new machine shows up with 1GB RAM, 20 GB HDD (dynamic allocated), 2 network adapters (1x NAT, 1x host only).




But it is not possible to create VMs on a remote Virtualbox server. The CLI does not allow to give a remote server IP:

But for some other environments it is possible to deploy VMs on a remote site:

--vmwarevsphere-vcenter: IP/hostname for vCenter (or ESXi if connecting directly to a single host)
If your preferred virtualization engine supports remote servers, you can check here:

Nevertheless docker-machine is an excellent tool. If you are interested in creating a swarm, read this tutorial.
The homepage of the OS boot2docker can be found here.

07.02.2018

Talking about Microservices: A journey to Docker / Snap / CoreOS / Unbuntu Core / Docker-Swarm

A few months ago (13th august 2017) i started my personal journey into this new hype called microservices:

I thought the best way for me to get in touch was to begin with CoreOS. Within 2 weeks i got some first impressions:

But after these steps i realized, that next step on this road is kubernetes. It is clear that cluster scheduler like kubernetes can not be run on a single machine - so i tried to get another access to microservices: Snap and UbuntuCore:
In november 2017 it was clear, that both UbuntuCore and CoreOS are some building blocks for microservices, but i was not really on the right track.
Back to kubernetes? Kubernetes relies on containers. So i started with docker:
Nearly 3 months later i still did not get in touch with kubernetes - but i think docker swarm is a cluster scheduler, too. And it is really easy to run.

What will i do next? Some tests to failure/failover/failback scenarios. 

03.02.2018

Ubuntu 17.10: s2disk/hibernate broken with kernel 4.13.0-32

Last week my notebook refused to startup after s2disk/hibernate. The resume process started up to 100% and then the screen went black and everything stopped...

Hmm...
First idea: Something disappeared inside the grub configuration.

But this was okay.

After nearly one hour my last try was booting an old kernel. And with
schroff@zerberus:/boot$ uname -a
Linux zerberus 4.13.0-17-generic #20-Ubuntu SMP Mon Nov 6 10:04:08 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
s2disk and resume worked again...