automount not working after macOS Catalina updates

I’ve recently upgraded to macOS catalina. My automount mount for music media was broken. I fixed it and today it is again not working.

The last change I did was to install the supplemental update for 10.15.7 which seems to overwrite the /etc/auto_master so my /etc/auto_smb wasn’t loaded anymore. Here’s my current working content:

#
# Automounter master map
#
+auto_master		# Use directory service
#/net			-hosts		-nobrowse,hidefromfinder,nosuid
/home			auto_home	-nobrowse,hidefromfinder
/Network/Servers	-fstab
/-			-static
/-			auto_smb	-nosuid,noowners

Don’t forget to run

sudo automount -vc

after it you’ve changed the file. Your automount should now work again.

Fix broken automount mounts on macOS Catalina

I’ve moved my iTunes music library content to my NAS. I’m using automount to keep iTunes happy without losing the connection to the files. After upgrading to macOS Catalina, automount did not work as it used to.

Reason is the changed structure in the APFS container. If you have a look at the disk utility, it will show you a system container and a user container. The system contains macOS and is write protected, while the user container contains all your apps, data and so on.

You’ll just have to prepend your existing automount paths with /System/Volumes/Data. Now you’ll just have to run

sudo automount -vc

and the automounts are working again.

I had to change the iTunes settings back to my automount folder, as the upgrade to Catalina reset it to its default location in your users folder.

Fixing Xcode command line tools after upgrade to macOS Catalina 10.15

Today I’ve updated to macOS Catalina 10.15. I’ve tried to setup zsh instead of bash and ran intro troubles with Xcode command line tools.

If I run

xcode-select -p
/Library/Developer/CommandLineTools

I’m seeing my previous installation in /Library/Developer/CommandLineTools. However, if I run

xcode-select --install

I’m seeing the installer which tries to fetch the latest Xcode command line tools. However, it always fails with

Unable to Download App. "Xcode" could not be installed. Please try again later.

I don’t intend to install the large Xcode from the appstore. So I’ve tried to delete the existing installation of the command line tools with

sudo rm -rf /Library/Developer

but the problem is still present.

Many people suggest to go to the developer.apple.com page and to search manually for the Xcode command line tools. I thought this wouldn’t work, because I’m only seeing the Xcode command line tools for Xcode 12.

However, we’re already at Xcode 12.1, so I thought this is the wrong download and is already outdated. But after I’ve installed the tools from this dmg, its working again and

xcode-select --install
xcode-select: error: command line tools are already installed, use "Software Update" to install updates

shows a suitable error message.

So lessons learned: using the latest major version of the command line tools installer seems to be sufficient.

Free purgeable space on MacOS Mojave

I’ve recently deleted a large preview database file for Lightroom and was happy about the 80GB won free space. However, the MacOS disk utility as well as the terminal command “df -h” did not show the free space. I’ve also checked the trash and cleared it, but there was no change in the available disk space.

I’ve taken a closer look at the free space column in the disk utility and found a new variable behind the available disk space: GB purgeable.

However, there is nowhere an option to purge this space. Upon further searching I’ve found this tip on stack overflow:

It looks like TimeMachine takes up a lot of free space in APFS snapshots which needs manual cleaning using this command:

tmutil thinlocalsnapshots / $((100 * 1024 * 1204 * 1024)) 4

This command tries to free 100GB space from the local snapshots. It’s using the highest priority (4) to speed up the cleaning.

After I’ve executed that command, the available free disk space was shown correctly again.

Disable macOS Catalina update notification in Mojave

macOS Catalina was released and is ready to install. If you’re using the previous macOS version called Mojave, you’ll get a notification badge on the system settings.

This little red notification badge is really annoying.

The following two commands were taken from the Apple support forum:

sudo softwareupdate --ignore "macOS Catalina"

If you want to install Catalina via the software update, you can reset the ignored updates with this command:

sudo softwareupdate --reset-ignored

This will hide successfully the Catalina update from the list of available updates in Software Update. However, it won’t remove the notification badge.

But fortunately you can even disable the badge by using these commands:

defaults write com.apple.systempreferences AttentionPrefBundleIDs 0
killall Dock

This will hide the badge until the next time you’ll scan for available software updates.