Using Munki’s force_install_after_date key to force items to install

Keeping machines up to date can be a challenge. Munki tries to make this as seamless as possible, especially if you mark certain items as unattended installs (Munki will try to install those items in the background and not even bother the user).

But some updates require a logout or a reboot, and users generally don't like to log out or reboot often, particularly if they have laptops (as opposed to desktops). So pending updates can sit there for days, weeks, months, even over a year, unless you force the user to install the items.

I wouldn't recommend using the force_install_after_date option very often, but it can be very handy, particularly if there are critical updates that need to get to users.

And even though Munki itself will attempt to notify users of forced updates, you may want to accompany those built-in warnings with warnings of your own (via email, in person, etc.).

At the final countdown, the screenshots below are examples of what your users will see. Every time there's an OK button in the Managed Software Center, your user has the option to close Managed Software Center for a short time, but then MSC will just pop back up again soon. At the very last dialogue, the user will have no choice but to install the pending install item.

Once again, use sparingly, but you may need to use it, so it's good to know roughly what your users will see...

Troubleshooting Munki failing to install Apple updates


If you see Apple updates (that require a reboot) not installing properly via Munki, it may be because the downloaded update is stale somehow. Not really 100% sure on how this works, since I've seen this fail even on a "stale" update downloaded the same day (not weeks ago).


When you log out to update, you'll see Munki's progress bar over the login screen window, and it will look for a split second as if it's trying to install the pending Apple update but then move on almost immediately to requiring a reboot.

Then, if you check the logs at /Library/Managed Installs/Logs/Install.log, you'll see something like

Apple Software Update install of Security Update 2017-001-10.12.6: FAILED for unknown reason


You could create a script (run from its own Launch Daemon or as part of a Munki run) to clear old updates from the /Library/Updates folder periodically (though, again, I saw this happen even with a recently downloaded update).

I've found that if you run

softwareupdate -d -a
the newly downloaded update will install just fine via Managed Software Center.

This is tricky, because it's not technically a Munki issue (Munki just uses Apple's built-in softwareupdate to install Apple software updates), but clearly there's some flaw in invoking the software update mechanism.

Deploying Munki with Mosyle MDM

Acknowledgements: This is a slightly modified workflow based on one proposed by Taz on MacAdmins Slack. Thanks, Taz!

You can use Mosyle to install Munki.

Switch to the macOS platform (if you're not already in there).

Then, click on Management.

Scroll down to and then click on Custom Commands.

Click Add new profile.

Name it whatever you want (e.g., Install Munki), and then put in a modified version of this code:


# Name of .pkg

# Desired hash output
desired_hash='MD5 (munkitools- = 0afbe2fbe7cb81ff531834cba82f3a75'

# Go to the /tmp directory
/usr/bin/cd /tmp

# Download the latest Munki tools .pkg
/usr/bin/curl -L -O"$munkitools"

# Make sure the hosting server hasn't been compromised and/or the download isn't corrupted
md5_test=$(/sbin/md5 $munkitools)

if [[ "$md5_test" == "$desired_hash" ]]; then

# Install the Munki tools .pkg
/usr/sbin/installer -allowUntrusted -pkg /tmp/munkitools- -target /

# Add in basic auth info
/usr/bin/defaults write "$3"/private/var/root/Library/Preferences/ManagedInstalls AdditionalHttpHeaders -array "Authorization: Basic BASICAUTHCODE"


Assign this profile to whatever devices or groups you want, and then click Save.

Any other Munki preferences (e.g., SoftwareRepoURL) you'll want to deploy in a .mobileconfig profile. More details in Importing custom .mobileconfig profiles into Mosyle MDM.

P.S. I haven't done extensive testing on this, but you may be able to deploy Munki as a .pkg and not as a custom command that downloads the .pkg. You'll have to host it somewhere yourself (and Mosyle does not like the redirect URLs, so you'll legit have to host it), but you may want to try Management > Management Profiles > Install App > Add new profile. Then, under Installation source, pick Enterprise app, and then put in the URL of the hosted Munki installer .pkg.

To change the icon, just get a .png of whatever icon you want. Here's an example of how to generate that:

sips -s format png /Applications/Managed\ Software\\ Software\ Center.icns --out MSC.png

Only caveat is that that won't work for scripting basic authentication.

Troubleshooting faded-looking icons in Managed Software Center on 10.13 clients

Update: Apparently, a real fix for this is on the way.

Acknowledgements: thanks to elios and bochoven on MacAdmins Slack for figuring out what was going on.

If the icons in your Munki repo looked fine on your 10.12 and 10.11 clients, and then a few of them suddenly look sort of faded (for example, Word and Excel in this screenshot) in 10.13 clients, it's apparently because of a change in the way 10.13's Safari webkit displays .png files missing the ColorSync profile in the Get Info context menu (you'll still see the ColorSync profile if you open the .png with the ColorSync Utility).

The simple fix is to do the following:

  1. Mount the Munki repo share using a Mac running macOS 10.13.
  2. Delete the offending icons from /PATH/TO/MUNKI/REPO/icons/
  3. Regenerate new icons with
    /usr/local/munki/iconimporter /PATH/TO/MUNKI/REPO

Note: Icons generated using MunkiAdmin or sips will be fine, too, even if generated using a machine running macOS 10.12.

Using Munki to manage Mac preferences with .mobileconfig profiles

You may sometimes script preferences using defaults write commands (don't edit the .plist files with a text editor directly). For example, you might change Munki client preferences using a command like:

sudo defaults write /Library/Preferences/ManagedInstalls SoftwareRepoURL ""
That's fine to do, but if you're actually managing Munki client preferences (not just for Munki-related settings but for other third-party or macOS settings), why not use Munki's built-in support for .mobileconfig profiles?

There are several methods to get or generate .mobileconfig profiles. I'm listing them below in order of preference from top recs to not-to-top recs.

Just finding existing profiles

Chances are if you want to manage a setting, someone else has also wanted at some point to manage that setting. mobileconfig is a great Google search for finding those.

Using mcxToProfile to generate a profile

You can create .mobileconfig profiles from existing .plist preference files you already have on a sample client machine. Just download Tim Sutton's mcxToProfile.

Then you can run something like

./mcxToProfile --plist /Library/Preferences/ManagedInstalls.plist --identifier MunkiPrefs
and then you can hand-edit the resulting .mobileconfig file to get out anything extraneous (for example, if all you want to set is the SoftwareRepoURL).

Generating Profiles with Apple Configurator

Apple Configurator is another option.

Just click File and select New Profile.

Once you've selected everything you want to configure, click Save.

The code it produces is (like mcxToProfile's) clean and easy to edit. And, yes, you usually want to edit down .mobileconfig profiles to be only the things you actually want to manage. Omit (i.e., delete) anything that you want your users to be able to manage themselves.

Generating profiles with Profile Manager

If you're using, there's a built-in way to generate profiles.

I usually create a test device group with no actual devices in it.

Then, under Settings, select Edit.

Find the type of setting you want to edit (there are some generic settings and then others specific to iOS or macOS). and click Configure and check off all the stuff you want configured.

Then once you've closed out of the editing settings space, click Save for the whole device group. This will allow you to download the settings.

Click the Download button and select macOS.

Now we're getting to why I seldom use Profile Manager. It adds in a bunch of binary gobbledygook and shoves all of the tags together so it's not easy to read. So, yeah, you can use it... but not fun.

Update: Apparently, you can tidy up the XML fairly easily if you want. Thanks to Ian Vonesh for the tip.

Whichever method you use, though, you can just import the .mobileconfig directly into Munki and push it out to your clients (be sure to test for unexpected behavior first before moving to production).

Can’t change Safari homepage in Sierra, even with no profiles managing homepage

So I came across something weird that's affected only my 10.12.4 clients (none of my 10.11.6 clients seem to be affected by this). Even though I have only one Safari profile enabled, which is set-once and doesn't manage the homepage, my 10.12.4 clients are unable to change the homepage in Safari manually. Whatever the homepage was is stuck like that. If you enter a new homepage in the Safari preferences, it will just not take and revert back to the old homepage once you hit Enter or click out of the address entry field.

The only workaround I've found for this is to delete all profiles (again, even though I don't have any profiles managing the Safari homepage):

sudo profiles -D
Are you sure you want to delete all configuration profiles? [y/n]:y
reboot the computer, and then reinstall (via Munki) all the previously installed profiles (yes, including the set-once profile for Safari that was installed before)... and then I'm able to change the homepage on the client manually. Very bizarre.

Also, after testing on a couple of other clients, there do seem to be situations in which the Safari profile was never set at all, and you still can't modify the homepage, even after deleting any other profiles and rebooting, and it's not account-specific either (freshly created account experiences it, too). It's a real head-scratcher.

Using startosinstall to install a macOS upgrade with Munki

Update: The instructions below will be obsolete once Munki 3 is released. More details on the Munki 3 implementation can be found on the Munki wiki.

createOSXinstallPkg is a great project for making an Apple macOS installer into a .pkg you can deploy with Munki.

Apple did some things to break that process for 10.12.4. People are in the process of finding workarounds for it.

One option is to use the built-in startosinstall tool that comes with the installer bundle.

If you import the bundle into Munki, you'll want to have both a preinstall_script and a postinstall_script.

The preinstall_script checks to make sure there aren't other updates pending, since startosinstall will run its own reboot independent of Munki. The pending updates should be 1 (it's the only 1) or 0 (it was part of a set of updates that did complete and then the pending updates cleared, and you're trying again):


# Make sure there is only one pending update (this one)
pending_count=$(defaults read /Library/Preferences/ManagedInstalls PendingUpdateCount)

# If it's 1 or 0, we're good to go
if [ "$pending_count" == 1 ] || [ "$pending_count" == 0 ]; then

exit 0


# Otherwise, abort the installation
exit 1

The postinstall_script does the actual install:

sudo "/Applications/Install macOS" --applicationpath "/Applications/Install macOS" --agreetolicense --nointeraction
Just as you would with a normal OS upgrade item, you want the installs array to reflect the OS version (not the presence of the installer bundle in the /Applications folder), and you want to mark this as an Apple item. (Check the Munki wiki for more details about those two things.)

P.S. There is now a recommendation on the createOSXinstallPkg README to upgrade using 10.12.3 or investigate using startosinstall.

P.P.S It's possible, instead of my funky workaround with the preinstall_script, that you could use the --pidtosignal option instead with Munki. Here's an example using JAMF.

P.P.P.S. Looks as if Greg Neagle has started working on integrating startosinstall into Munki "natively"—yes!

Automating an AutoPkg Munki import when vendors don’t package installers properly

You may have, when using (or creating) a .munki AutoPkg recipe, come across a situation in which you run it:

autopkg run -v NAMEOFITEM.munki
and then get something back like this:
Item NAMEOFITEM already exists in the munki repo as OLDNAMEOFITEM.
even though you're sure the item is newer than the one in the Munki repo.

That has to do with the find_matching_item_in_repo() function the MunkiImporter processor uses to determine whether the item exists already or not.

It compares a number of things between the to-be-imported item and what's already in the Munki repo—installer item hash, installs, receipts, files and paths, etc. If any of those matches up, MunkiImporter considers it a match.

So, for example, if you have BADLYPACKAGEDBYVENDOR 3.7.3, which is an update for BADLYPACKAGEDBYVENDOR 3.7.2, but the receipts for both are just 1 (yes, 1 and not 3.7.2 or 3.7.3), the MunkiImporter processor will see the two as the same and not do "another" import of the same item. Likewise, if the version in the app bundle is 3.7 and not 3.7.2 or 3.7.3, the MunkiImporter processor will see them as the same. I've even run into situations in which a vendor artificially ups the number but the "new" package or .app bundle is exactly the same. In that case, the installer hash will be the same, and the MunkiImporter processor will see them as the same.

So what do you, apart from complain to the vendor and pray it fixes the problem?

There may not be anything you can do apart from force an import. You may find a convoluted workaround, though. For LockDown Browser, I had to create an installs array based on the executable and also essentially override the useless receipts array. You might have to do something similar, depending on how bad the vendor package is.

Using an Outset boot-every script to add default applications via Munki

In Bash script to add optional installs for Munki, I introduced a script that uses PlistBuddy to add optional install items to the client machine's SelfServeManifest.

I thought at first I could use that as a boot-once script for Outset, but it seemed the script ran too early (actual first boot) and then didn't actually write the values it should.

As a workaround, I've put the script in as an Outset boot-every with a check to see if one of the optional items is already in the Munki install log. Here's an example:


# See if this has ever run before... have to check the log, because Outset will delete the file once run. We don't want this to re-run if we update the pkg version
alreadyRun=$(cat /Library/Managed\ Installs/Logs/Install.log | grep "Firefox")

if [ -z "$alreadyRun" ]; then

# Self-serve manifest location
manifestLocation='/Library/Managed Installs/manifests/SelfServeManifest'

# PlistBuddy full path

# Add in "optional" default software

# Check to see if the file exists. If it doesn't, you may have to create it with an empty array; otherwise,
if [ ! -f "$manifestLocation" ]; then
sudo "$plistBuddy" -c "Add :managed_installs array" "$manifestLocation"

for packageName in "${optionalDefaults[@]}"
# Check it's not already in there
alreadyExists=$("$plistBuddy" -c "Print: managed_installs" "$manifestLocation" | grep "$packageName")

# Single quote expansion of variables gets messy in bash, so we're going to pre-double-quote the single-quotes on the package name

if [ -z "$alreadyExists" ]; then
sudo "$plistBuddy" -c "Add :managed_installs: string $alteredPackageName" "$manifestLocation"

So this basically checks for Firefox. If Firefox (one of the default optional installs) is in the install log, it won't run again.

When an AutoPkg recipe fails to import a .dmg

If you ever have an AutoPkg recipe that seems to be working fine for weeks or even months and then suddenly fails with a message like this one:

Error in local.munki.FileZilla: Processor: MunkiImporter: Error: creating pkginfo for
/Users/USERNAME/Library/AutoPkg/Cache/local.munki.FileZilla/FileZilla.dmg failed: Could not mount
(doesn't have to be FileZilla—could be anything), you may not see the .dmg is mounted in Disk Utility (or even diskutil list), but you can check to see if it's a phantom mount by seeing if it shows up in the output of
hdiutil info
If it does show up there, then run
hdiutil detach /dev/diskFILLINLOCATION
and then re-run the recipe. Should be fine after that.

Acknowledgements: Thanks to Eric Holtam for the tip—just documenting it here for anyone else who may benefit from it.