I'm running Ubuntu 20.04 on one drive (m.2) and Win10 on another (3.5" SSD). I recently added another m.2 drive to my system and cloned my Win10 system onto it. So here's what my drives look like now, where sda1 and nvme1n1p1 are clones:
root@cantankerous:~# lsblk -f
NAME FSTYPE LABEL UUID FSAVAIL FSUSE% MOUNTPOINT
sda
└─sda1 ntfs 9638B89D38B87E35
nvme1n1
└─nvme1n1p1 ntfs 9638B89D38B87E35
nvme0n1
├─nvme0n1p1 vfat 23FD-2B75 478.1M 6% /boot/efi
└─nvme0n1p2 LVM2_member cKt344-wOPa-y34D-j0Wg-y3wq-ZlFz-fIGpnr
├─vgkubuntu-root ext4 27945eb2-45c3-48da-b887-6391111416e3 328.4G 23% /
└─vgkubuntu-swap_1 swap 9bdb7f2f-ac7b-4322-ae8e-38c870a190cc [SWAP]
I'd like to get rid of /dev/sda now.
I believe that what I need to do next is use efibootmgr to modify my bootable drives. Right now my EFI files live on the nvme0n1 drive that houses Ubuntu. Here's the output of efibootmgr:
root@cantankerous:~# efibootmgr -v
BootCurrent: 0000
Timeout: 1 seconds
BootOrder: 0000,0002,0008,0001
Boot0000* ubuntu HD(1,GPT,9ab61c6d-62f6-474f-99c4-64eae4e5b595,0x800,0x100000)/File(\EFI\UBUNTU\SHIMX64.EFI)
Boot0001* Windows Boot Manager HD(1,GPT,9ab61c6d-62f6-474f-99c4-64eae4e5b595,0x800,0x100000)/File(\EFI\MICROSOFT\BOOT\BOOTMGFW.EFI)WINDOWS.........x...B.C.D.O.B.J.E.C.T.=.{.9.d.e.a.8.6.2.c.-.5.c.d.d.-.4.e.7.0.-.a.c.c.1.-.f.3.2.b.3.4.4.d.4.7.9.5.}....................
Boot0002* Hard Drive BBS(HD,,0x0)..GO..NO........q.S.a.m.s.u.n.g. .S.S.D. .9.7.0. .E.V.O. .5.0.0.G.B....................A...........................%8Z.........4..Gd-.;.A..MQ..L.S.4.6.6.N.X.0.K.A.6.2.1.5.9.H........BO..NO........u.S.H.G.P.3.1.-.5.0.0.G.M.-.2....................A.......................................8..Gd-.;.A..MQ..L.C.S.0.9.N.5.2.4.9.1.0.2.0.9.G.3.K........BO..NO........u.S.a.m.s.u.n.g. .S.S.D. .8.5.0. .E.V.O. .2.5.0.G.B....................A.................................>..Gd-.;.A..MQ..L.2.S.5.R.X.N.H.A.0.3.4.9.1.2. .Z. . . . ........BO
Boot0008* Windows m.2 HD(1,GPT,2aba441a-2647-48c4-868c-b4ca31d4f5a3,0x800,0x3a385800)/File(\EFI\MICROSOFT\BOOT\BOOTMGFW.EFI)
I've tried using efibootmgr to create a new bootable entry, but what I can't figure out how to do is specify that, although the EFI image lives on "nvme0", I need it to boot onto "nvme1". I see this being done with /dev/sda with this "bcdobject=([uuid])" but I can't find any information out there about how this is done.
That is, of course, assuming I'm on the right track!
Once that's done I'm assuming os-probe will pick up the new drive and I can integrate it with grub-mkconfig.
Thanks for any help!