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Apple's Policy on Apple File System (APFS) for High Sierra

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unser system information / storage O get :
Partition Map Type: Unknown
Is that normal ?

uBtqbAZ.png
 

jaymonkey

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unser system information / storage O get : Partition Map Type: Unknown ... Is that normal ?


@tabarus,

Not sure if it "Normal" but I too get "Partition Map Type: Unknown"
on my HP Spectre X360 Laptop running MacOS 10.14.6 :-

Screenshot 2019-07-25 at 13.20.07.png
A quick search on the Apple forums shows that its a very common reported issue effecting a lot of genuine Macs.

My guess is that Apple may write some sort of extra meta data to the GUID partition table when it is initialised with Mojave Disk utility, if the GUID partition table is an existing one created on an earlier version of MacOS then it wont have the extra data resulting in the "Unknowen" flag .... this is just a guess mind but could be easily confirmed.

It could also be possibly linked to something to do with a lack of a T2 security chip.

Update: I've done some further testing ... seems to make no difference if GUID partition scheme is freshly initialised on latest Mojave or done with an older version of MacOS, so that kind of blows my meta data theory out of the water.

It could be a bug in MacOS but i think it's more likely something to do with the T2 chip ... which is why many genuine Mac owners are also seeing it (there are a lot of current Mac models that do not have T2).

Would be interesting to get to the bottom of it though, just for peace of mind.

Cheers
Jay
 
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I can confirm I have the same "unknown" on an M2 SSD prepared/formated/installed with Mojave 10.14.4
 
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