Tag Archives: OS X

Computer Management – Additional Configurations for Reformatted Xserves

Sean got the remaining Xserves configured to run independently from the master node of the cluster they belonged to and installed OS X 10.11 (El Capitan).

The new computer names are Ostrich (formerly node004) and Emu (formerly node002).


He enabled remote screen sharing and remote access for them.

Sean also installed a working hard drive on Roadrunner and got that back up and running.

I went through this morning and configured the computers with some other changes (some for my user account, others for the entire computer):

  • Renamed computers to reflect just the corresponding bird name (hostnames had been labeled as “bird name’s Xserve”)

  • Created srlab user accounts

  • Changed srlab user accounts to Standard instead of Administrative

  • Created steven user account

  • Turned on Firewalls

  • Granted remote login access to all users (instead of just Administrators)

  • Installed Docker Toolbox

  • Changed power settings to start automatically after power failure

  • Added computer name to login screen via Terminal:

sudo defaults write /Library/Preferences/com.ap\ple.loginwindow LoginwindowText "TEXT GOES HERE"
  • Changed computer HostName via Terminal so that Terminal displays computer name:
sudo scutil --set HostName "TEXT GOES HERE"
  • Installed Mac Homebrew (I don’t know if installation of Homebrew is “global” – i.e. installs for all users)

  • Used Mac Homebrew to install wget

  • Used Mac Homebrew to install tmux

Docker – VirtualBox Defaults on OS X

I noticed a discrepancy between what system info is detected natively on Roadrunner (Apple Xserve) and what was being shown when I started a Docker container.

Here’s what Roadrunner’s system info looks like outside of a Docker container:


However, here’s what is seen when running a Docker container:



It’s important to notice the that the Docker container is only seeing 2 CPUs. Ideally, the Docker container would see that this system has 8 cores available. By default, however, it does not. In order to remedy this, the user has to adjust settings in VirtualBox. VirtualBox is a virtual machine thingy that gets installed with the Docker Toolbox for OS X. Apparently, Docker runs within VirtualBox, but this is not really transparent to a beginner Docker user on OS X.

To change the way VirtualBox (and, in turn, Docker) can access the full system hardware, you must launch the VirtualBox application (if you installed Docker using Docker Toolbox, you should be able to find this in your Applications folder). Once you’ve launched VirtualBox, you’ll have to turn off the virtual machine that’s currently running. Once that’s been accomplished, you can make changes and then restart the virtual machine.


Shutdown VirtualBox machine before you can make changes:


Here are the default CPU settings that VirtualBox is using:



Maxed out the CPU slider:




Here are the default RAM settings that VirtualBox is using:




Changed RAM slider to 24GB:




Now, let’s see what the Docker container reports for system info after making these changes:


Looking at the CPUs now, we see it has 8 listed (as opposed to only 2 initially). I think this means that Docker now has full access to the hardware on this machine.

This situation is a weird shortcoming of Docker (and/or VirtualBox). Additionally, I think this issue might only exist on the OS X and Windows versions of Docker, since they require the installation of the Docker Toolbox (which installs VirtualBox). I don’t think Linux installations suffer from this issue.

ISO Creation – OpticonMonitor3 Disc Cloning

Since many newer computers are coming without optical disc drives (including my laptop, which I want to install this software on), I created an .iso disc image of the OpticonMonitor3 (BioRad) installation disc.

Using OS X Disk Utility:

  1. File > New Disk Image

  2. Dropdown > CD/DVD Master

This creates a Mac-specific .cdr image of the installation CD. Converted to a universal .iso disc image with the following command line:

$hdiutil makehybrid -iso -joliet -o [filename].iso [filename].cdr

Replaced [filename] with OpticonMonitor3.

Moved the newly created OpticonMonitor3.iso file to our server (Eagle/Backup/Software/Windows).

Now the .iso file should be able to be mounted and installed on any Windows computer without the need for a physical installation CD.