Deploying a Mac Server with GSX

Recently, I was asked by a friend to fix a Mac server I had set up a while back. Unfortunately, the server was borked beyond repair, so a reinstalllation of the OS was necesssary. This did cause me to look back at the guide I wrote for myself back in 2013. Below is an editted version of that guide for posterity should anyone else need it. I know it helped my friend setup a new server just fine. The guide is a tad dated, but not much has changed in the past three years (luckily).


  • This is a compilation of the knowledge I gained doing this.
  • Everything here is possibly deprecated by the time you read this, keep yourself updated.
  • Be willing to fail and you will make it.
General Rules
  • I recommend not having more than 8 computers per serve. For load balancing reasons, that is all.
  • If you do use the computers for something, please delete anything you put on them. It doesn’t need to be cluttered and slow because it is a server.
Setup NetInstall
  1. Get a Mac for a server if you don’t already have one. We are using a Mac Mini 2012.
  2. Install Mavericks, or what ever the latest OS is.
  3. After installing OS X, go to the App Store and download the Server App provided by Apple. Will cost you $20, which ain’t too bad for upfront costs.
  4. Run the server app. On first time setup, it will walk you through what it wants. Create an admin account and such, and select this Mac as the server, not an extension of it (you can do that later if you want multiple servers for load balance).
  5. Go to NetInstall and turn it on.

You now have a working NetInstall Server. However, you still can’t diagnose things. You will need to log onto GSX (Apple’s online website for authorized people and companies). More on that later.

Imaging Explained

Here is where the process gets tricky. NetInstall allows OS X machines to boot over the network and onto the server for new images of an OS. From my understanding, here is the differences between the following options. You have three: NetBoot, NetInstall, and NetRestore.

  • NetBoot: Allows you to boot into an image of OS X to run over the server to a machine. Pretty much allowing your machine to be a slave and run off the server. Good if the internal hard drive of the machine you are dealing with can’t boot at all.
  • NetInstall: Allows the machine to boot into a standard OS X installer, or a customized one if you want to do that. Note that, in this instance, if you have custom packages you want to install that have serial numbers wrapped in, this is not a good choice. The packaging app will strip your custom installation package of those scripts.
  • NetRestore: Here is where things get cool. From my research, earlier models of OS X (like, pre Lion) required you to be model specific (e.g. an iBook image can’t be installed on a Macbook, and a G4 image can’t be installed on a G5). I read somewhere online that the later models could be used for earlier models, but I can’t confirm this. Now, as of Lion the image is very generic, and should, in theory, allow you to image from one computer to another with no problem. This is useful because you can create an image that has all your software on it. Here’s the catch: it requires a recovery partition. What does this mean? It means we need a separate computer that can be reimaged and used to produce new images. This means that every time an image needs updating, you take your spare computer and update it, then capture a new image. I have read online that OS X can apply updates to existing images.

And finally, the last most important thing I have found: from my understanding, you can only create images that are of the same OS system as the server. That means Mavericks can only create Mavericks, Mountain Lion for Mountain Lion, etc. This is a huge pain because of the amount of work that will go into it.

Apple Service Toolkit (AST)

Before using AST, we use to use ASD (Apple Service Diagnostics). These were system specific images distributed by Apple that ran full scans on the specific computer model we wanted. The problem with this is that it took us upwards of 40 minutes just to burn one of these to a flash drive to diagnose one computer. We don’t have that type of time, and we didn’t have a ton of flash drives, so we ended up reburning over and over again . Inefficiency is bad. This is not to say ASD is useless. I would recommend using it on systems that can’t do AST.

Why AST?: AST take exponentially less time. You boot over the network from the computer you plan on using. It will show you the diagnosis related to your computer. It has a GUI interface, so use the mouse and pick what you want.

  • MRI: The most generic one is MRI. This does a full hardware test, and grabs system info like serial numbers and things while you are at it. It takes between 1-3 minutes
  • Pixel test: This tests the screen for dead pixels Those are the ones that show up on most Macs. Newer Macs, meaning ones using retina displays, have a screen image retention test.
  • Retention Test: By requirement, and from what I have been told by a Genius, you CANNOT look at the screen while this test is running. The image is a black and white checkboard, and your brain is stupid and will remember the image for longer, even if not retained. You have to look at the result (which takes about 5 minutes to complete) to determine if there is an issue. Now, the rest of the tests are pretty self explanatory, so I won’t go into them here. The last thing I will say is that you can also boot into our NetInstalls from this system, which is quite nice.
Running on Pre-2006 Mac:

From my understanding, AST only supports from 2011 up for specific hardware tests. Anything before then won’t see the NetBoot images AST can support as far back as 2006, as ASD has been integrated into AST as of 2014 (thanks Obstfreak for the correction). However, here are your options with pre-2006 Macs:

  1. Hold N on boot and run MRI.
  2. Burn an ASD image and run the test that way (although MRI is way faster).
  1. Go to GSX.
  2. Got to “Reference” section. Looks like a bunch of books.
  3. Search for “Apple Service Toolkit”. I kind of just found my way to it, so I can’t say I have an exact science to finding it.
  4. Download Gateway Manager (fair warning, this app is garbage).
  5. Download ALL of the available ASTs and their parts.
  6. Setup Gateway Manager. It will ask you for credentials.
  7. Follow the instructions on Apple setup guide to properly enter the required info from GSX so you can activate Gateway Manager. IF YOU DON’T DO THIS, IT WON’T WORK.
  8. Gateway manager can tell you what ASTs are installed, and what needs updating, so please check it every month or so and stay updated. On install, it will setup the things required to have AST show up on the network. Every time you install a new AST, it will be added automatically to the bootable files.

Creating NetRestore Images

  1. Acquire the most recent model Mac you can find. For the purpose of this, based on the restriction I currently work with, I am using a Mac Mini 2012 with Mavericks.
  2. Install the most recent revision of the OS with the most recent updates installed.
  3. Reboot the computer and hold the OPTION key.
  4. Verify there is a restore disk, this is critical!
  5. Reboot again, this time hold T. This will put the computer in target disk mode. Grab a firewire cable (or thunderbolt) and connect it to the server.
  6. Go to Finder and verify you can see the disk properly.
  7. Go the server app and launch System Restore Utility from Tools in the menu bar.
  8. Select the hard drive of the target disk computer from the drop down menu.
  9. At this point in time, we have nothing we want to customize about this install, so select “Net Restore” from the options, and proceed to click “Continue”. Name it what you want, and give it a description, then let it create the file once you click “next”.
Proper Restoration Procedure
  1. Boot mac that is to be restored while holding OPTION key.
  2. Select the NetRestore image from the bootable network options (the ones with the globes).
  3. This will boot into a NetRestore installer. You can access terminal and disk utility like you would in a normal OS X installer (in tools) should you need them.
  4. Wipe the disk of the computer by going to Disk Utility and selecting the internal drive and erasing everything on the partition. We want to start fresh.
  5. Quit Disk utility
  6. Go select the internal drive for installation and click “Continue”.
  7. Let it run, should take about twenty minutes give or take depending on things.
  8. Once done, let the computer reboot and boot normally.
  9. Open up all the standard software and verify the products are all registered with the valid keys (online registration accounts don’t matter right now)
  10. Run software updates and verify there aren’t any new OS X updates needed.
Updating Restores

You can only update restores by creating new ones if you used a target Mac to capture the restore. If you are using NetInstalls, you can run the combo updater on the image and not have any problems.

06/06/2016 - Revised with typo correction courtesy of Obstfreak.

Written on February 19, 2016