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LaurentR2D2

macrumors member
Original poster
Jul 24, 2011
94
8
Paris - France
Hello,

Wishing to create a bootable clone with Chronosync, I followed the instructions on their site (https://www.econtechnologies.com/chronosync/tn-cs-bigsurbootable.html) and I launched the installation of Big Sur on my external SSD (WD My Passport SSD 1Tb) following the instructions on this site (https://www.macworld.co.uk/how-to/macos-external-drive-3659666/) after having erased it using the APFS format recommended on the Carbon Copy website for the SSDs. The installation went well until the reboot. There, in Boot Security Utility, I set Secure Boot to Normal Security and checked Allow booting from external or removable media. I selected the SSD in the boot drive choice window and that's when the system refuses to boot by displaying the message SDErrorDomain error 104. I have already deleted the SSD twice. I tried the third time to erase the SSD using Mac OS Extended (journaled) and GUID Partition Table, but the Big Sur installer tells me that my SSD is not compatible with this version of the operating system (Mac OS Big Sur 11.6.1). I have an iMac 2020 Corei9 / AMD Radeon Pro 5700 XT 16 Go

Thanks
 

davidlv

macrumors 65816
Apr 5, 2009
1,381
60
Kyoto, Japan
Hello,

Wishing to create a bootable clone with Chronosync, I followed the instructions on their site (https://www.econtechnologies.com/chronosync/tn-cs-bigsurbootable.html) and I launched the installation of Big Sur on my external SSD (WD My Passport SSD 1Tb) following the instructions on this site (https://www.macworld.co.uk/how-to/macos-external-drive-3659666/) after having erased it using the APFS format recommended on the Carbon Copy website for the SSDs. The installation went well until the reboot. There, in Boot Security Utility, I set Secure Boot to Normal Security and checked Allow booting from external or removable media. I selected the SSD in the boot drive choice window and that's when the system refuses to boot by displaying the message SDErrorDomain error 104. I have already deleted the SSD twice. I tried the third time to erase the SSD using Mac OS Extended (journaled) and GUID Partition Table, but the Big Sur installer tells me that my SSD is not compatible with this version of the operating system (Mac OS Big Sur 11.6.1). I have an iMac 2020 Corei9 / AMD Radeon Pro 5700 XT 16 Go

Thanks
First, you must use the APFS and GUID Partition Table format, Mac OS Extended (journaled) hasn't worked since Mojave.
The author of CCC doesn't recommend using a bootable disk anymore, he suggests a backup disk created by CCC is sufficient. The Apple method in the URL below will work, and then you can use Disk Utility to create other Volumes on that disk if you need to store other files on that backup bootable disk. Due to Apple's implementation since Catalina, the external boot disk method has become quite complex. See the URL below for the necessary info about creating that external bootable disk.
 

LaurentR2D2

macrumors member
Original poster
Jul 24, 2011
94
8
Paris - France
First, you must use the APFS and GUID Partition Table format, Mac OS Extended (journaled) hasn't worked since Mojave.
The author of CCC doesn't recommend using a bootable disk anymore, he suggests a backup disk created by CCC is sufficient. The Apple method in the URL below will work, and then you can use Disk Utility to create other Volumes on that disk if you need to store other files on that backup bootable disk. Due to Apple's implementation since Catalina, the external boot disk method has become quite complex. See the URL below for the necessary info about creating that external bootable disk.
Ok. Thank you for the explanation. I guess I'll follow the advice of the CCC developer. Bootable disks were interesting, though, not only to boot from my Mac, but also from someone else Mac when traveling. I hope Apple will find a way to let this things done again.
 
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