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Converting a volume of an MBR SSD to GUID via terminal using usb mac installer

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Can a volume of a mbr disk be partitioned into GUID to install macosx using mac usb installer in terminal? My same SSD has a windows os and I cant lose data. I am not able enter either OS at the moment. I need a GUID to finish mac install. Helpp

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Answer is no.

 

A volume is a disk partition and cannot be further partitioned... One can only adjust partition sizes of a disk and add/remove partitions.

https://en.wikipedia.org/wiki/Disk_partitioning

https://coriolis-systems.com/static/support/help/iPartition/pgs/schemes.html

https://www.howtogeek.com/193669/whats-the-difference-between-gpt-and-mbr-when-partitioning-a-drive/

 

MBR and GPT/GUID are disk partitioning schemes. On a given disk, only partitions formats can differ and co-exist, not partition schemes which are unique. It's not very common to convert disk partitioning from one scheme to the other but there are tools to do so. Usually, one simply entirely wipes out a disk and starts afresh with the desired/target partition scheme.

 

If you're trying to install OS X/macOS on an MBR disk, you need to apply the MBR patch. Whatever you attempt or decide to do with your SSD, there's only 1 thing to do if you cannot lose your data...

 

NB: no multiple posting on the forum for the same matter please!

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Sorry about the multiple posts. So if I want to install El capitan on an MBR disk, can I apply the patch out of os? I cant get into either os at the moment. Let me google it first. Thanks for your help Herve.

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How were you able to install OS X on this MBR partition in the first place?

You patch the MBR on the installer.

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i see. i decided to format the whole disk into  GUID and installed El Capitan 10.11.6 and its running great, thanks to all the hard work guys. Now I have another 128gbs of space in which I want to install windows 10 and dual boot. I tried formatting the remaining portion as MS DOS FAT but windows denied to install as it only accepts GPT when booting from UEFI. Few questions if I may bother you:

 1. How can I convert the remaining space into GPT or whatever that i can install windows on it?(Same SSD,2partitions)

 2. Is there a way I can get my RAID functionality back in Mac OSX so that it opts my disk performance?

 3. I was thinking of updating to Sierra, I read the guide clearly for Sierra, so do I simple update from App store and run the terminal command for the trackpad or do I need to change the bootpack, create an installer usb and redo all again.

Long query ,pardon my ignorance. Learn a lot from you guys in 3 days. Fun too. 

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to install windows you would have to reformat the empty partition as hfs journaled. then boot the windows installer as UEFI. during windows install select the partition your going to use for windows. delete it and install windows to it.. after windows installs sometimes you have to go into bios and re select clover as the boot source or sometimes you have to reinstall clover.

 

 software raid usually does not work on osx with the exception of bios hardware raid. but even that sometimes has issues as well. maybe switching to SSD will give you the performance your looking for.

 

if using clover you should be able to just upgrade from the app store app. depending on the model the trackpad kext might need to be updated to a compatible version as it might cause a kernel panic.

 

for backup you should be able to use disk utility from the recovery partition to clone osx to another drive and or partition. there are third party apps that can do it from a live osx boot as well. if you want the new back up to be bootable you will have to copy your existing EFI folder and also put it on the backup drive EFI partition.

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Thanks

 

Appreciate your detailed reply. In fact I tried to install windows after formatting the drive as HFS journaled, but the windows installer didn't allow me to write on the disk (run as uefi, and it did format too). I used the clover guide by Jake for el  capitan, so i may directly upgrade to sierra with no problems as u mean. thanks

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