Kev’s Blog – Page 150 – Kev's Development Toolbox

July 13, 2016

Installing kernel headers for Oracle Linux 6 on VirtualBox

The usual reason for Guest Additions failing to install on a Linux guest on Virtual Box is that the kernel headers are missing. How you install these or where they come from varies from distro to distro, although they’re usually available via the package manager on that distro.

I had an Oracle Linux 6 guest installed, Guest Additions (for video drivers, shared folder, clipboard sharing) was all working, and then at some point I started it up again and it was no longer working and wouldn’t re-install either. Seems like I’d picked up an update, and I needed to update the kernel headers too.

This post covers the steps needed. On OE6 before installing the Guest Additions, just run ‘yum install kernel-uek-devel’ and you should be good to go (assuming you’re booting with the ‘unbreakable kernel’ and not the RHEL compatible kernel)

July 12, 2016

Configuring a static IP on HypriotOS for the Raspberry Pi

How you configure a static IP on the Pi changed between Wheezy and Jessie, and it seems on Hypriot’s prebuilt images for running Docker on the Pi, it’s a slight variation.

Edit /etc/network/interfaces.d/eth0, comment out the DHCP line:

iface eth0 inet dhcp

and add:

iface eth0 inet static
address your-static-ip
gateway your-gateway-ip
#google dns servers
domain_name_servers=8.8.8.8, 8.8.4.4

Done!

July 12, 2016

Docker 1.12 RC on the Raspberry Pi

If you’re excited about playing with the swarm mode in the new 1.12 version of Docker, you can download the release candidates for Linux, Windows, Mac, but it’s not obvious where you can get an ARM compatible version to run on the Raspberry Pi.

The awesome guys over at Hypriot talk about running the 1.12 RC on the Pi, but their prebuilt OS images for the Pi don’t yet include the 1.12 RC version. I found this blog post however, which mentions a download location where you can pick up a .deb file and install it on the Pi with dpkg.

Downloaded, installed on my “to be” Pi cluster of 2 Pis, and up and running! Now to deploy something with swarm 🙂

July 11, 2016

Mac Docker 1.12.0-rc3-beta18 native client and insecure registry

A while back I set up a local Docker Registry to share images between different machines, and configured it as an ‘insecure registry’ since it’s just for testing. With the latest native Docker engine for Mac OS, I was having difficulty pushing to the Registry, it was just fail with a cryptic message:

$ docker push 192.168.1.66:5000/rpi-mongodb

The push refers to a repository [192.168.1.66:5000/rpi-mongodb]

Get https://192.168.1.66:5000/v1/_ping: http: server gave HTTP response to HTTPS client

I noticed in the Docker menu from the menu bar that there’s a Insecure Registries section under Preferences, Advanced Options. Adding the IP and port of my Registry there fixed my problem, now I can push:

$ docker push 192.168.1.66:5000/rpi-mongodb:latest

The push refers to a repository [192.168.1.66:5000/rpi-mongodb]

3d4f4a09f67b: Pushed 

fc91d495516f: Pushed 

5f70bf18a086: Pushed 

532820a7256b: Pushed 

ed62ae893def: Pushed 

994d5442545b: Pushed 

f097d343f850: Pushed 

latest: digest: sha256:c71c6743924243d6117050a1b5b95adf4effee7c9059315c0bfe500f67e0d16b size: 260