Upgrade to High Sierra on Single Dual-Boot SSD W10/Sierra possible?

[warbird69]

I recently installed Windows10 and macOS Sierra on a Lenovo Y50-70 as dual boot on a single SSD, following the great guides on this site.
For this was my first touch with a hackintosh i have no further experience. So i wonder whether i could upgrade my Sierra partition to High Sierra without loosing my Windows10 installation.
Is it possible to upgrade and convert to APFS just the macOS partition with leaving the rest untouched?
What about keeping the HFS+ Filesystem as described in the guide? Will this be a secure way or perhaps the only way?
Are there any disadvantages expected when running High Sierra on HFS+?
Lots of Questions i know, but i am sure some of you guys can make some good suggestions.
Sure i created backups, but i am a bit frightened anyway.

 

[warbird69]

Well i was too curious to wait and for having everything backed up and time left, i gave it a try.
In my case it was not possible to upgrade a dual boot single ssd configuration without loosing the win10 partition, because after downloading high sierra the system destroyed my win10 partition and created an "install high sierra" partition instead without asking me.
I now will let the upgrade process finish and figure out, if everything is working. Then i try to recreate the second partition an try to put the win10 backup to it.

 

[diep90]

it works.

i have a SSD nvme M2 with 3 partions.

1. APFS for macOS
2. APFS for macDATA
3. NTFS for windows 10

 

[anor4k]

Well i was too curious to wait and for having everything backed up and time left, i gave it a try.
In my case it was not possible to upgrade a dual boot single ssd configuration without loosing the win10 partition, because after downloading high sierra the system destroyed my win10 partition and created an "install high sierra" partition instead without asking me.
I now will let the upgrade process finish and figure out, if everything is working. Then i try to recreate the second partition an try to put the win10 backup to it.

Weird, I upgraded mine and the Windows 10 partition was untouched. It converts your macOS partition into an APFS partition, which shows up as a different drive in Disk Utility.

 

[warbird69]

However, in the end the upgrade to High Sierra worked fine for me with no issues. The file system was converted to APFS and everything like sound, wifi, bluetooth, etc. is working without me having to do anything.
I will recover my Windows 10 installation later either on the same ssd or another. The main thing is that i lost no data.
This thread may be closed.