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MacOS Catalina has a dedicated system volume now
- Thread starter STOCK411
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"I've been doing it since then too." When parenthetically it was "illegal", "unsupported" and Apple would not talk to you if they knew the OS was ona partitioned drive. It was/is the only safe and logical way to keep your files safe and easy way to reinstall the OS when it hammers, and it will and does . . . About time they caught up. First Dark Modes and now "Auto-Partitioning". I can only imagine what 10.16 will have that we've been doing for decades.
I have not checked into the details, but the folder hierarchy is likely handled through mount points to look as usual.
Looking at my unsuccessful boot attempt it symlinks everything back to root. I got a heap of "invalid current symlink" and "create_symlink" errors
Also, looking at the installer /Applications has moved to /System/Applications, and /Library is empty (though I can't see where it's gone just looking at the installer). This is probably why my system was unbootable. I used the OSInstall framework from 10.13 as per https://forums.macrumors.com/thread...ave-and-keep-hfs.2138162/page-3#post-27400317, but it doesn't know about ROSV so it didn't set up the root volume correctly. The installer has a flag called '__ROSV_CREATE_SYMLINKS' so I'll be playing with that.
Interestingly I also saw a references to 'APFS condenser' - maybe ROSV will give us a compressed system volume, so that macOS installs slim down by ~5GB!
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Interesting enough, many windows users tend to separate their personal files, installed programs and system into three partitions back in windows xp. Every time I see this, I often tell them “just install all programs in C drive as you will need to install most of those programs anyway if you want to reinstall the system”.
So, things I've found:
- The contents of your 'Data' volume are pre-populated from the install location at /System/Library/Templates/Data
- Installing to one partition then manually copying the data from System/Library/Templates/Data to a volume does not result in a bootable system, at least if both are HFS+ and are seperate partitions rather than in the same APFS container
I'm currently testing two further things:
- Imaging a copy of the APFS container to a disk image, then restoring that image to a physical disk
- Using ditto or CCC to copy the individual volume contents from the image to newly created partitions
One other thing I've found is that there appears to be a new APFS 'role' type, of a "System" partition. I have't tried 'diskutil apfs changeVolumeRole' in Catalina, but in High Sierra the options are 0 for non, B for preboot, R for recovery and V for virtual memory. It recognises the system type but I cannot change the role to 'System'
- The contents of your 'Data' volume are pre-populated from the install location at /System/Library/Templates/Data
- Installing to one partition then manually copying the data from System/Library/Templates/Data to a volume does not result in a bootable system, at least if both are HFS+ and are seperate partitions rather than in the same APFS container
I'm currently testing two further things:
- Imaging a copy of the APFS container to a disk image, then restoring that image to a physical disk
- Using ditto or CCC to copy the individual volume contents from the image to newly created partitions
One other thing I've found is that there appears to be a new APFS 'role' type, of a "System" partition. I have't tried 'diskutil apfs changeVolumeRole' in Catalina, but in High Sierra the options are 0 for non, B for preboot, R for recovery and V for virtual memory. It recognises the system type but I cannot change the role to 'System'
If we can disable the read-only then I'm fine with that.
A separate partition for the OS is what I've been doing for the last two decades, so I'm ok with that also.
A separate partition for the OS is what I've been doing for the last two decades, so I'm ok with that also.
Can you explain what is the volume clicker? and how do you do that?
Tried to install the beta today in an APFS container. I guess it decided my Quota of 32GB wasn't valid, and just made its own new container with no Quota. I was annoyed enough at having an extra volume on my desktop wasting space for the beta, but two? No thanks.
I'm really curious what sort of linking mechanism is used to link, for example, /Users to /System/Volumes/Data/Users and so on. From the UNIX shell, /Users just looks like another directory. But when you cd into it, df . now tells you that you're in a different filesystem.
Various commands to examine files, like stat, file, ls -l, and so on don't provide any useful information. It looks like a frickin' directory. There's no bind or loopback mounts that I can see.
This is confusing, and as a 24 year UNIX veteran it's frustrating to not be able to see EXACTLY what's going on with my filesystem.
Various commands to examine files, like stat, file, ls -l, and so on don't provide any useful information. It looks like a frickin' directory. There's no bind or loopback mounts that I can see.
This is confusing, and as a 24 year UNIX veteran it's frustrating to not be able to see EXACTLY what's going on with my filesystem.
I’m curious too. It’s as if it’s mounted back to /, but I can’t tell how. This explains why just copying the data to the ‘- Data’ partition doesn’t allow for a bootable system
I think doing this has broken a bunch of apps that require the tmp folder.
Tunnelbrick doesn’t work on Catalina at the moment. It doesn’t even seem to be able to install properly.
Tunnelbrick doesn’t work on Catalina at the moment. It doesn’t even seem to be able to install properly.
I’ve just been able to successfully restore a disk image (captured in Mountain Lion) to a raw disk using High Sierra. So, whatever voodoo causes the data volume to be linked to the system volume is restorable.
I had to create an empty GPT entry for an APFS container, then use diskutility to restore container to container. I kept getting ‘cannot set UUID’ errors otherwise.
Edit: I’m back in the installer. Valid roles for APFS in Catalina are: 0, b, r, v, i, t, s, d, u, n, e, x, h, l, c, y, g (found from ‘diskutil apfs changeVolumeRole). I have to wait for this install to finish, but after that I want to check the man page for diskutil to see what the alphabet means. Diskutil apfs changeVolumeRole its dune?
I had to create an empty GPT entry for an APFS container, then use diskutility to restore container to container. I kept getting ‘cannot set UUID’ errors otherwise.
Edit: I’m back in the installer. Valid roles for APFS in Catalina are: 0, b, r, v, i, t, s, d, u, n, e, x, h, l, c, y, g (found from ‘diskutil apfs changeVolumeRole). I have to wait for this install to finish, but after that I want to check the man page for diskutil to see what the alphabet means. Diskutil apfs changeVolumeRole its dune?
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https://developer.apple.com/videos/play/wwdc2019/710/
This answers just about all the questions about the read-only system volume. This session video just went live some time today.
This answers just about all the questions about the read-only system volume. This session video just went live some time today.
I wonder if this is why things broke when I tried to roll back to Mojave? I kept getting a 9000f error on my MBP after erasing and trying both regular and internet recovery. Made a bootable USB of Mojave and that failed too. It was bypassing the Mojave install and going to Internet recovery and failing with the same error.
Finally managed to get it to recovery but all I can do is reinstall Catalina. Trying that for the time being until I can properly roll back.
Finally managed to get it to recovery but all I can do is reinstall Catalina. Trying that for the time being until I can properly roll back.
I've just watched the first few minutes. This new "Firmlink" sounds good. I've had issues with apps such as OneDrive where I've wanted to link a directory into its folder so it gets synchronised. Dropbox has no issues with symlinks but OneDrive refuses to follow them. Maybe this new firmlink will solve my issue.
For those who don't want to watch the video ... the system volume is writeable in this beta. In future, it will be read-only. SIP can still be disabled which makes the volume writeable but only until the next reboot. In other words, compared to Mojave, disabling SIP does not survive a reboot.
It’s frustrating!
Does anyone know if the main Library (not Users/~/Library, the main one) is covered by this read only stuff? Trying to figure out if I can force this thing to install...
If it behaves like Mojave, the correct install location for kexts is /Library/Extensions. Installing into /System has actually been deprecated always.
I thought something looked odd. On that note, does Catalina still allow kexts at all, or are they specifically disallowed in favour of driverkit?
That’s kind of what I figured...
Is there a way to recompile this thing so it installs in the proper places and has a newer unexpired certificate?
Wow, just wow. As a sysadmin who uses ZFS day to day, this is all incredibly familiar. APFS is becoming like Apple's version of ZFS. I'm quite pleased with this!
I have not investigated what kept support looks like yet. If it will work at all, you’ll definitely need to extract the files and install manually (you can do this with a tool called Pacifist, which has a free trial). You’ll probably need to load the kext manually and nearly definitely have to disable SIP.
Mid start with the man page for the ‘kextload’ tool on Catalina and see what it tells you, if it still exists.