No NetBoot, No problem: installr and bootstrappr

It’s 2019, and NetBoot is almost dead. All new Macs have T2 chips. Sent from the future to protect us from …. ourselves? No more NetBoot, no problem!!

When NetBoot first appeared and I was able to boot entire labs of Macs across the network I was amazed and overjoyed. It was awesome. Spinning globe, spinning…

Netboot-GlobeSpin.jpg

But in the years since I’ve moved on to no-imaging. Using Munki to manage software means no more imaging, just install Munki and a small config change to point to the Munki server, thereafter the software that should be there goes on, and what’s not supposed to be there goes away. Simple. Just install one package, well, maybe two, then you’re good.

Well, what if you want to streamline or automate these things? What if these are new Macs which don’t have users configured? What if we could do all this from recovery mode? Hmm… Enter bootstrappr and installr!!

bootstrappr

This awesome project allows to add packages to install in one step while booted in recovery mode. Plug in a USB stick with the bootstrapr script to run the package install magic or mount a disk image over http. Create a DMG with the included script make_dmg.sh. And now this is the best part: in recovery mode open the Terminal app from Utilities and type:

hdiutil mount http://server/yourDMG.dmg

Then:

/Volumes/bootstrap/run

When it’s done you can Reboot the Mac and you’ll have a set up customized to your liking with Munki installed and configured with custom settings.

installr

The installr script works in the same way but adds the macOS installer to the party. You can also mount the DMG over http and re-image a Mac and then add your custom packages. It’s awesome. Truly amazing.

One note: Added packages in Installr must be in a special format. From the installr site: startosinstall requires that all additional packages be Distribution-style packages (typically built with productbuild) and not component-style packages (typically built with pkgbuild)

productbuild --package component.pkg --version x.y --identifier com.example.component distribution.pkg

In one of my first tests with installr and pycreateuserpkg I was caught up by this, even though it is properly mentioned in the read me. Packages that work in Bootstrappr or munki directly don’t necessarily work when called by the macOS installer (startoinstall). Armin Briegel was helpful in the MacAdmins Slack and reminded me of this. Thanks Armin and thanks everyone on the MacAdmins Slack.

Many Thanks to Greg Neagle for creating these tools and Munki. Looking forward to hearing him speak at the next MacDevOps:YVR conference June 12-14, 2019. Greg will be speaking about his efforts to port some parts of Munki from Python to Swift. More info on the conference and speakers here: https://mdoyvr.com/speakers/

Also a shout out to Graham Gilbert who has worked on Imagr (MDOYVR talk), over the years, an imaging and automation tool which was also an inspiration (along with bootstrappr and installr) to Tim Perfit and his MDS project.

Update: corrected the names of installr and bootstrappr in the title because… autocorrect.

 

Reset Printer Queue

TIL (thing I learned)

Had a user upgrade to macOS 10.14.1 and no printers showed up anymore.

So using my Google fu I found some posts (see one below) which described a novel way to reset the print queue on macOS. An old trick apparently. Learn something new everyday.

A quick trip to a terminal and it worked! The existing printers returned to System Preferences and printing resumed.

$ cancel -a

Reference

Blocking minor major macOS upgrades

Continuing our theme of welcoming our new macOS overlords, uh, I mean, blocking major macOS upgrades such as macOS 10.14 Mojave with AppBlock we shall examine some other methods of stopping the freight train known as Apple upgrades.

1) A smart person on the MacAdmins Slack posted a useful command to tell macOS not to download major upgrades.

In their testing, running:

`software update –ignore macOSInstallerNotification_GM`

blocks the installation of the Mojave notification package (at /Library/Bundles/OSXNotification.bundle).

However if it already installed, then it’s too late. They pushed out this command prior to that package being distributed by Apple, and they could subsequently see in install.log that the update is being found by softwareupdated but not being installed.

2) If you missed the chance to tell the Mac not to download major macOS upgrades then Rick Heil on his blog has detailed a way using munki to delete the bundle that triggers the macOS upgrade installer.

3) App Block

If your users are intent or their computers are all hell bent on downloading the install app then block it with App block detailed in my previously mentioned blog post

4) Warning

In an effort to get an early warning when users are about to upgrade I use Watchman Monitoring to send me an alert email when a Mac starts downloading the Install macOS app. Sometimes it’s enough of a warning to send an email to a user to ask them whether it is a good idea to upgrade at this time. If storage or software needed for production or backups aren’t qualified or tested thoroughly beforehand then upgrading in the early waves can be less than ideal and frought with peril.

In other interesting and related news, Victor (MicroMDM) was spelunking into the MDM Protocol for what prompts Macs like iOS devices to download major updates. Great post here

If you have any better ways to block macOS upgrades or want to contribute some great solutions let me know. Cheers

 

 

 

 

To install macOS Mojave, or not to?

InstallMojave

Just the other day macOS Mojave was released and now the armies of Macs armed only with the AppStore are silently downloading the installer and ready to upgrade. You can’t hurry too fast to be on the bleeding edge, hurry faster!

Just in case you don’t want everyone to install macOS 10.14.0 (dot zero!) in the first week of its release here’s a way to slow down the upgrade hordes using Erik Berglund’s AppBlocker script. Erik Berglund is also the author of ProfileCreator (for creating profiles) and the author of many other great scripts.

Note: for true binary whitelisting check out Google’s Santa project and Upvote (and Moroz and Zentral, two other Santa sync servers).

Step 1. Get it

Clone or download the AppBlocker project from GitHub

AppleBlockerProject.png

Step 2. Do it

Edit the AppBlocker.py script with the Bundle Identifier of your app to block, in this case for the Mojave installer from the AppStore it is:

com.apple.InstallAssistant.Mojave

You can also edit the alert message, and the icon that is shown, as well as decide if the blocked app should be deleted or not. The script is easy to edit in BBEdit, or nano (in Terminal). Use whatever your favorite text editor is to make the necessary changes.

# List of all blocked bundle identifiers. Can use regexes.
blockedBundleIdentifiers = ['com.apple.InstallAssistant.Mojave']

# Whether the blocked application should be deleted if launched
deleteBlockedApplication = False

# Whether the user should be alerted that the launched applicaion was blocked
alertUser = True

# Message displayed to the user when application is blocked
alertMessage = "The application \"{appname}\" has been blocked by IT"
alertInformativeText = "Contact your administrator for more information"

# Use a custom Icon for the alert. If none is defined here, the Python rocketship will be shown.
alertIconPath = "/System/Library/CoreServices/CoreTypes.bundle/Contents/Resources/Actions.icns"

UPDATED NOTE:

To determine the Bundle identifier of other applications you can use osascript

osascript -e 'id of app "iTunes"'
com.apple.iTunes

If you want to block more than one app use a comma separated list in the AppBlocker.py script:

['com.apple.InstallAssistant.Mojave','com.apple.iTunes']

 

Step 3. Run it

Put the script where you want to run it. The default location as defined in the launchd plist included with the app is “/usr/local/bin”. Put the launchd.plist in “/Library/LaunchDaemons/” and start up your launchd to block your apps!

launchctl load /Library/LaunchDaemons/com.github.erikberglund.AppBlocker.plist

Step 4. Automate it

For bonus points we automate! Bundle it all up in a package with munkipkg, then distribute it with Munki to all your clients.

Using munkipkg is easy. Create the folder using munkipkg

./munkipkg --create AppBlocker

munkipkg: Created new package project at AppBlocker

Then you fill the payload folders with those items you downloaded from the AppBlocker project. LauchD plist in the LaunchDaemons folder and AppBlocker.py in the “usr local bin” (create each nested folder).

AppBlocker-Munkipkg3.png

And finally create a post install script (no “.sh”) with the launchctl action to start your plist.

AppBlocker-Munkipkg4.png

Last but not least add this package to your Munki repo as an unattended managed install  that everyone gets. Of course, only do this after testing your package locally somewhere to verify that it works properly. Remember the saying: “You may not test very often, but when you do it’s always in production.” Be very careful with your testing but always automate all the things.

Updated after the initial blog post to explain how to add more than one app to block, and how to use osascript to determine the bundle identifier.

 

 

 

Root Me Baby One More Time!

UPDATE: Apple has posted a security update. 2017-001

Root-a-pocalyse. Root down. Root a toot toot. Many funny tweets today about a very serious issue. A bug was discovered in macOS 10.13 that enabled anyone to login with a root account. With no password. Wow. Seriously. Yeah, that’s bad.

Bug discovered by Lemi Orhan Ergin.

I tested by clicking on the lock icon in System Preferences. Normally this requires an admin account. I was able to authenticate with “root” and no password. This actually also set root to no password. You can choose a password here and this makes it for you. How convenient. You can also login to the Mac via the login window. With root. And no password. Crazy.

If your Mac is off it’s safe. Not joking. If your FileVault protected drive is encrypted and your mac is turned off then you’re good. If you Mac is turned on and you’ve logged in at least once (or at least decrypted the drive on boot) then you’re not safe.

What can you do? Change the root password and set the shell to false. Until Apple fixes this. Should be anytime now. Or soon.

dscl . -passwd /Users/root “random or very secure password here”

dscl . -create /Users/root UserShell /usr/bin/false

Read a comprehensive explanation on Rich Trouton’s site:  Der Flounder blog

 

My Thunderbolt Nightmare

It was a dark and stormy night of cables and capacitors when suddenly I heard the door knocking, or was something falling of a shelf? I was in a cramped server room, if you’d call it that, and I was day dreaming, sorry, night terrorizing, of days gone past when I worked in nice big well ventilated server rooms with proper enterprise gear. Oh wait, did I really dream that? Did it really happen? Maybe it was less well ventilated and there were cables strewn about the tall 42U shelves and sometimes we found a Mac hidden underneath spaghetti. Sometimes. I vaguely remember the long shiny metal servers, they talked to me, they sang, a whiny pitch of whale song. Dream on, dream on.

Now. Today. Apple Music on my iPhone plays every single Arcade Fire album in a long playlist, in order. And I follow the white rabbit of Thunderbolt cables. This is my thunderbolt nightmare. Dead drive in a Thunderbolt Promise Pegasus unit, web ticket filed for registered hardware. Legacy. That’s the word they used. Where’s Marshall McLuhan when you need a proper redux of the shit storm you’re in? Thunderbolt 3 uses USB-C and everything is possible. Can’t wait to step into that confusing identity crisis. OK, back to the present day when I stared at the red blinking drive, a replacement drive from not long ago dead again, sitting in the last row of a now legacy Pegasus R6 unit. RAID 5, the most dangerous kind, this is what stood between me and uncertainty. The worst kind of RAID. Well, not as bad RAID 0. Raid nothing. Raid 5 is one bad drive away from a bad day. Backups? Hmm, I got those, I got plenty of those, but I don’t want to be tested today. No, not today. Not this bloody day.

I open the Pegasus utility and the GUI wants an update. Hmm, that’s not in autopkg, I think. Why is out of date? Munki let me down. I start to drift, to side shift into adding newer better recipes to autopkg, to tweaking my Munki repo, to what sessions would be awesome at the next MacDevOps:YVR conference. Gee whiz, I love open source, and everyone in the Mac Admins community…. Snap out of! I slap myself in the face. I was hallucinating. Stay on task. I update the Pegasus utility. I stare at the critical reports from one of the three R6 units attached to this Mac Mini server. Did I say server? But it’s so small, so little. It works. It’s magical, kinda neat. Until you stare too close at the back. The Thunderbolt cables go from the Mac Mini to the first Pegasus unit to the SANlink fibre channel adapter to the LTO 6 tape library to the next Pegasus utility to the second SANlink adapter to a third and final Pegasus RAID unit. What’s is going on? Where does this cable go? Let me just follow it to the next jumping off point. My brain slows, the lack of oxygen in this cold machine room start to affect my thinking. I lose my way.

I download the report for the Pegasus unit. I had to unlock a pretty neat lock icon and click on the save report. I upload it to the web support and add it to the ticket. Tech support gets backs to me in a day and said all is good, and to carry on. I can’t. The drive is dead. What are they not seeing? It’s right in front of me. I download the report again. Again the same response. Fine. It’s time to stop messing around and pop open Terminal. Loading up promiseutil I check out the options and switches and get into an argument with myself about the currently valid optionals of letters and numbers that are required. I check my notes, online knowledge base, and try again. It’s broken. It doesn’t work. Stumbling around the command line typing imprecisely incorrect statements gets nowhere fast. I realize that there’s no way for the cli utility to properly change its focus to the broken unit with the busted drive. Both the GUI and the binary are stuck on the one R6 unit and won’t see what’s in front of my face.

I call tech support. This is humiliating. This was supposed to be easy. Drive dead, drive reported, drive ordered, drive replaced, then no one the wiser. Data saved, not dead. Backups not tested. Not today. No, not today. Tech support treats me like the imaginary newbie IT people sometimes treat everyone with. He repeats his instructions to me. He is polite. Download the report. I can’t. It won’t work. Unplug the unit. Plug it into something else. I can’t. The cables. The Thunderbolt cables are everywhere. It’s magical, and daisy-chained, and stuck. “Can I remote in and see?” he asks, hoping to resolve this quickly. Sorry. That’s impossible. Even if I thought it was a good idea. I remind him that I have a dead drive. That’s why I called. I want to get a replacement drive. “Sorry sir that legacy unit is not under support most likely,” I know that. I realize that now. That I wasted my time. It happens sometimes. The truth is staring at you. You need a mirror to see. “You need to order compatible drive from the compatibility list.” I am a well spring of emotions. I thank him. I am nice. He was polite. But now I know what I need to do. Oh wait, what? Order a drive now! Order two.

McLuhan never had a chance to evaluate Thunderbolt storage technology but the insane genius and simplicity of Thunderbolt reduced expensive enterprise fibre channel storage to the dust bin. Magical SAN for video editing with a Mac Mini and Thunderbolt RAIDs. Cheap enough to buy with a departmental credit card, fewer meetings to attend, more films to shoot and edit. Backup, archive, repeat. McLuhan would have no doubt reminded me that the tetrad of technology would have flipped Thunderbolt on its head, Fibre channel never went into a dust bin, but was firmly relegated to well cooled storage room, and long ago legacy drives in the enterprise units are humming a long while the cursing wind and emotions swell over the Thunderbolt mountain. Fibre channel just became cool again. Retro smart.

Troubleshooting Autopkg and AutoPkgr (part 1 of 5,432)

I love Autopkg and Autopkgr. They feed Munki and they keep me fed.

Sometimes Autopkg gives an error that doesn’t make sense since you don’t have enough info. Like this one:

autopkgr-work-tree

That’s no way to make friends. Nope.

If even I understood all that… which is saying a lot. It doesn’t tell us what to do, or where to go to fix it.

Git makes sense, but maybe not in the context of Autopkgr errors. It wants us to “Git add or rm” (remove) offending items, but what does it have to do with what we’re doing at this moment? Hmm. Ok, we know  that autopkgr uses autopkg which uses git but that still leaves us in the dark about what’s going on.

Drop down in terminal and poke at autopkg. That always helps.

bash-3.2$ autopkg

Usage: autopkg <verb> <options>, where <verb> is one of the following:

    help             (Display this help)

    info             (Get info about configuration or a recipe)

    install          (Run one or more install recipes. Example: autopkg install Firefox -- equivalent to: autopkg run Firefox.install)

    list-processors  (List available core Processors)

    list-recipes     (List recipes available locally)

    make-override    (Make a recipe override)

    processor-info   (Get information about a specific processor)

    repo-add         (Add one or more recipe repo from a URL)

    repo-delete      (Delete a recipe repo)

    repo-list        (List installed recipe repos)

    repo-update      (Update one or more recipe repos)

    run              (Run one or more recipes)

    search           (Search for recipes on GitHub.)

    version          (Print the current version of autopkg)

autopkg <verb> --help for more help for that verb

Looking at all that we notice that “repo-update” is most likely the autopkg command that gets activated when Autopkgr gui “update repos now” button gets clicked.

screen-shot-2016-09-29-at-10-26-20-am

Running autopkg with repo-update option gets us a better error message.

Attempting git pull for /Users/awesome/Library/AutoPkg/RecipeRepos/

com.github.autopkg.wardsparadox-recipes...

ERROR: Pull is not possible because you have unmerged files.

Please, fix them up in the work tree, and then use 'git add/rm <file>'

as appropriate to mark resolution and make a commit.

So, at least we know now what is causing that error that Autopkgr showed us. Quick fix:

autopkg repo-delete https://github.com/autopkg/wardsparadox-recipes.git

And then we go on and pretend like nothing happened and continue on with our day, amirate? Maybe we go to the Mac Admins Slack autopkg channel and ask our colleagues, or  post on the autopkg mail-list. Or we write a blog post.

More information:

The Autopkgr read me has troubleshooting tips

In the archives:

I first wrote about troubleshooting Autopkgr 2 years ago