new nvme and sata will not boot

[oldfred]

If removing SATA drive then allows NVMe drive to work, check your motherboard manual.
Many disable a SATA port to enable NVMe.

[VMC]

...

Can you tell me why there seems to be 2 UUID's for the partition? as thus:

/dev/sdg5: UUID="70afb10c-38bf-4edd-a070-24b1b3ddb1b5" TYPE="ext4" PARTLABEL="kubuntu20" PARTUUID="ebbbae4e-77b2-474d-9f2e-28f2869dfe2c"

The tune2fs command only changed the first bit........

why are there two for each one? Why on earth do they have to make things so bloody complicated? GRRRRRRR!!!

Are you referring to the PARTLABEL? If so read this:
https://unix.stackexchange.com/quest...uid-and-ptuuid

The partition number is inside the PARTLABEL (see sudo blkid -p)

You just need to change UUID.

[vidtek]

If removing SATA drive then allows NVMe drive to work, check your motherboard manual.
Many disable a SATA port to enable NVMe.

Been there done that oldfred....along with countless others I spent a whole day trying all the various options....and gave up on that route along with everyone else!

[vidtek]

Are you referring to the PARTLABEL? If so read this:
https://unix.stackexchange.com/quest...uid-and-ptuuid

The partition number is inside the PARTLABEL (see sudo blkid -p)

You just need to change UUID.

It still seems inordinately complicated for simply identifying a partition. I suppose it's all because of different file systems and encryption methods.

I'll bet all the same info could be put in a simple 8-bit string.

Why do they make stuff so unnecessarily complicated...seems to me it is just designed to baffle the uninitiated. The modern equivalent of religious "educated" men in the middle ages keeping everything in latin so their parishioners are in awe of them.

[vidtek]

OK guys, I finally have an answer.
I was playing around with gdisk (as you do) and came across this little gem in the expert menu (highlighted in red).

root@linuxmint:/home/tony# gdisk
GPT fdisk (gdisk) version 1.0.5

Type device filename, or press <Enter> to exit: /dev/sdg1
Partition table scan:
  MBR: MBR only
  BSD: not present
  APM: not present
  GPT: not present


***************************************************************
Found invalid GPT and valid MBR; converting MBR to GPT format
in memory. THIS OPERATION IS POTENTIALLY DESTRUCTIVE! Exit by
typing 'q' if you don't want to convert your MBR partitions
to GPT format!
***************************************************************


Command (? for help): ?
b       back up GPT data to a file
c       change a partition's name
d       delete a partition
i       show detailed information on a partition
l       list known partition types
n       add a new partition
o       create a new empty GUID partition table (GPT)
p       print the partition table
q       quit without saving changes
r       recovery and transformation options (experts only)
s       sort partitions
t       change a partition's type code
v       verify disk
w       write table to disk and exit
x       extra functionality (experts only)
?       print this menu

Command (? for help): x

Expert command (? for help): ?
a       set attributes
c       change partition GUID
d       display the sector alignment value
e       relocate backup data structures to the end of the disk
f       randomize disk and partition unique GUIDs
g       change disk GUID
h       recompute CHS values in protective/hybrid MBR
i       show detailed information on a partition
j       move the main partition table
l       set the sector alignment value
m       return to main menu
n       create a new protective MBR
o       print protective MBR data
p       print the partition table
q       quit without saving changes
r       recovery and transformation options (experts only)
s       resize partition table
t       transpose two partition table entries
u       replicate partition table on new device
v       verify disk
w       write table to disk and exit
z       zap (destroy) GPT data structures and exit
?       print this menu

Expert command

With this one change I was able to boot from the nvme or sata drive.

Steps to get it going:

1. boot as normal from nvme drive
2. after linux boots connect sata drive (I just connect via USB3 from my docking station)
3. open command prompt and sudo or su for root prompt
4. list disks I use blkid
5. once you know the disk device designation, open gdisk
6. enter device name into gdisk prompt eg. /dev/sdg (as in my case)
7. press x for expert menu
8. then just enter the letter f
9. w for write your changes then q for quit out of gdisk
10. I installed Grub Cutomizer as it make life so simple otherwise make your manual grub changes to add the sata drive to the boot menu
11. reboot

That's it, I was even able to once again boot my windows 10 installation from the sata drive via usb3 connection from my turbo lepoard docking station. So much for Microsoft's much vaunted "you can't boot windows form an external drive mantra". I will take a video of the booting process and upload it to my mega cloud storage if anyone is that interested, I'll edit this and post the link here when I've done it.

I want to thank all for their help with this, particularly VMC & OldFred for pointing out the issue was probably the partition UUID's. Spot on guys!