Anders Jensen-Waud

In this brilliant blog post at Aeon Magazine, the author explores the hypothesis that the technology that we have built is making the World too complex. As he puts it, “human ingenuity has created a world that the mind cannot master.” We have embedded complex systems – through science, information systems, and engineering excellence – […]

I just installed the newest version of WordPress. I am wondering how this is going to pan out. I switched back from Ghost as I was sick of writing markdown for everything.
Stay tuned.

I am currently working on OpenBSD 5.5 (amd64) running in a virtual machine using VirtualBox on my Mac. After installing the guest machine, I expected being able to ssh to it via the IP assigned to the virtual network interface:

# ifconfig em0
inet 127.0.0.1 netmask 0xff000000
em0:
[...]
 inet 10.0.2.15 netmask 0xffffff00 broadcast 10.0.2.255

In my case I had configured the network adapter with NAT (Native Address Translation), which means that the host machine acts as DHCP server and router for the guest.
Hoping I could reach the guest via its IP in the NAT virtal network, I switched to the OS X terminal and did:

$ ssh aj@10.0.2.15

… and no luck. Something is in the way.

It seems that, in order to ssh to a Virtualbox guest, you need to enable port forwarding between the host and the guest(s) you want to access. Open the VM settings > Network and select the network adapter (in my case Adapter 1). Create a new rule with the following attributes:

• Name: SSH-host (or whatever you like)
• Protocol: TCP
• Host:
• Host port: 2222 (this is the TCP port you will use on localhost to connect to the guest)
• Guest IP:
• Guest Port: 22 (this is the SSH TCP port)

Press OK and open a prompt on your host machine to connect to the VM:

# ssh localhost -p 2222
Last login: Wed Jun 11 19:56:32 2014 from 10.0.2.2
OpenBSD 5.5 (GENERIC.MP) #315: Wed Mar  5 09:37:46 MST 2014

The rule opens a TCP port (2222) on localhost of the host machine, which is then tunneled to any arbitrary port on the target machine (port 22). In order to enable easy to my VMs, I copy my public key across using ssh-copy-id:

$ ssh-copy-id localhost -p 2222 -l aj

Voila!

Desparately needed this one after tinkering with a ZFS rolling backup script:

sudo zfs list -H -o name -t snapshot | xargs -n1 zfs destroy

Note: This will remove ALL snapshots. Use at your own risk.

I recently installed a new FreeBSD 10 server at home (on my trustly old IBM Thinkpad). After seeing that openjdk8 was out, I thought I would install it from ports and give it a spin.
During installation I received the following kernel warning in my SS…

I have been addicted to IRC ever since my first days as a mIRC scripter back in 1996-1997 and the true wonders of DALnet and DCC chat. After I jumped the Slackware Linux wagon in 1998 I was first introduced to X-Chat as the “one true IRC client”. Howev…

There are certain good tools, which are so good that it is really hard to let go of them for something else or new. In my worklife, I have three favourite tools, which are an embedded part of my daily workflow:

Vim
FreeBSD
PowerPoint

Yes, an esote…

I have recently spent some time on configuring Ghost on my FreeBSD server. For various technical reasons the default Ghost deployment model running on sqlite3 does not work on FreeBSD (I get some mysterious build errors when running npm install –produ…

Welcome to my new blog on jensenwaud.com powered by Ghost 0.4.0. It is a very exciting new piece of technology compared to my old Wordpress powered site. I can’t wait to start a new round of blogging on this page!

Best regards

Anders

PS: I still hav…