13.08.2017

First step to micorservices: CoreOS on virtualbox (1)

I read some articles about microservice architecture and about kubernetes / apache mesos.
My conclusion from these articles is, that lightweigt servers are a key point to this microservice architecture. Just to learn how tiny such a OS could be, i will try to install CoreOS inside virtualbox.

There is an easy way to get CoreOS running ("booting CoreOS container linux from ISO"), but there some limitations stated on the CoreOS website:

  1. There is no straightforward way to provide an Ignition config.
  2. A mininum of 1024M of RAM is required to boot Container Linux via ISO.
So just download the iso image coreos_production_iso_image.iso and create a virtualbox vm:





 Then mount the coreos_production_iso_image.iso as boot cd/dvd
 and here we go:
At this point we have something like a live cd running. Because nothing was installed on the hdd and it is not possible to umount the ISO image.

How to get from this point to a installed operating system on disk, i will show in a following posting.

10.08.2017

(bash): The most useless commands (9)

After talking about
  1. rev
  2. yes
  3. sl
  4. cowsay
  5. cmatrix
  6. cal
  7. rig
here another pretty useless command:



$ pi 10
3.141592653
Manpage:
DESCRIPTION
       The  pi  command  prints  100 decimal digits of Archimedes' constant pi or a number of
       digits specified by an integer parameter on the command line.

25.07.2017

Ingress: Level 16 reached...

After long time playing google/niantic's ingress (the predecessor of pokemon go - all the arenas are portals in ingress, most of them created by ingress players) i reached the last level:



And the usual welcome package:


I am wondering, wether i should continue playing or quit the game for now or ever.
Perhaps reading this discussion (What do lvl 16 players play for?) may help me.