Performance Magic

Ramblings from a Sysadmin

September 20, 2017

Containers Not Just For Docker

Over the past year (or more really) containers has been a big thing and specifically Docker, and I suspect so much so that many people believe that docker and container are synonymous. This is far from the truth. Docker is really a nice wrapper that uses containers (or should that be name-spaces?) to provide a method of distributing and deploying a single application. Containers are really just a name-space in Linux which lets you control some of the resources within that name-space. ... Read more

August 30, 2017

brew install version

I work with several clients and often we are using different version of tools at different times. While I’m endeavouring to move my development processes to use docker containers I still do a lot of development locally on my Mac. I’m still running Mac OS (or is that OS X??), and so I use brew to install many of my tools. What I’ve struggled with in the past is installing certain versions of the many tools. ... Read more

November 24, 2016

Why I prefer GNU Linux

As many people know I usually use a GNU Linux desktop environment, and have for a few years. I have previously had to use Windows during stints at large Engineering orgs, but most of the time, I was able to setup a second computer with Linux on it for day-to-day tasks. I’ve also used macOS/OS X a few times in the last few years, and I’ve got pretty frustrated with it. ... Read more

July 17, 2015

The saga of the AirBag Warning Light

About 6 months ago our car (2008 Nissan X-Trail) started to have it’s AirBag light flash. This could be a worry we thought. After some googling we found a way to reset or go into a new diagnoses mode. This involved carefully timed ignition key turning with the airbag light showing up on the dash. (as it turns out there are at least a couple of these combinations which interact with various systems in the car) ... Read more

August 17, 2014

Community Hubs

I have been putting a lot of thought recently into how the Australian and NSW government are pouring money into road infrastructure in Sydney. I think they are about 20 years too late, and believe they should stop throwing that money away and change directions. We are living in a world where telecommuting is a reality. I am fortunate enough to work for a great company where I can do that. ... Read more

August 17, 2014

Is it the cache?

We do a lot of support of OpenSource CMS’s at work, and one of them happens to be WordPress. I recently thought it might be cool to have a bit more of a play with W3-Total-Cache as it is a plugin of choice to assist customer with scaling issues. Since my blog is massively popular (not!), I decided to use the S3/CloudFront option, presented here. Well it didn’t work. Very sad face. ... Read more

June 22, 2014

Adventures in Go and File Handles

I’ve been mucking a bit with go recently. Nothing special, just doing some small problems that I needed to solve. At work, I have built up a challenge for new candidates. One of them is the old trick of using all the inodes on a file-system. This is a quick one to rule out the ones who have real world experience. So I wrote some code: `I’ve been mucking a bit with go recently. ... Read more

April 21, 2014

Crashplan GUI Won’t run in Trusty Tahr

I upgraded my laptop to Trusty Tahr today. One thing that didn’t work immediately was the Crashplan GUI. It crashes with a SIGSEGV. In summary “C [] soup_session_feature_detach+0x11”. I managed to find this bug, and then I found /usr/local/crashplan/bin/run.conf  which has a variable GUI_JAVA_OPTS. Adding ” -Dorg.eclipse.swt.browser.DefaultType=mozilla” to the end of that variable, and the GUI starts without fail. Win!

November 11, 2013

Grow VDI Disk (VirtualBox)

There is no way to grow a disk image in virtualbox via the GUI, but you can do it on the CLI. First list all the hdds and then grab the UUID of the disk you want. Then modify the hdd with the modifyhdd command and specify the new size in MB. `There is no way to grow a disk image in virtualbox via the GUI, but you can do it on the CLI. ... Read more

July 21, 2013

Error: Acquire running lock failed: 256

Recently had a OVS root file system fill up due to a run away iSCSI process (and I don’t even use iSCSI…). This had a side affect of affecting almost any task that needed to interact with the Xen hypervisor (status, start, stop, etc). Once I had worked this out and cleaned up the logs to gain space back, I had one VM which was in a very upset state and couldn’t be started, shutdown, anything. ... Read more

© Greg Cockburn