btrfs preventing installation of grub2
 

Yesterday I was installing btrfs when I gave the fatal command to format a partition but forgot the partition number! So the drive was wiped and the functioning RAID devices (a RAID1 and a RAID5) were decommissioned. I used sgdisk to duplicate the partition structure from a mated disk and got everything working again.

I went to install grub2 from a chroot into the newly formatted and set up disk and received the following unpleasant news:
This was odd, because I installed grub2 before I wiped the disk when it was similarly set up. I consulted the great guru Google, and found that someone else had the same experience after reformatting a btrfs drive and found that there were crumbs left over from the previous formatting. He got rid of those and voila! Grub installed.

So I checked for my own crumbs. A standard command yielded the following:
All good, and as it should be. But then I used the command used by the person in the forum I consulted and got the following:
Omigod! It listed not only the expected btrfs arrays but also the UUID that resulted from the accidental reformatting of the entire drive! This, I am guessing, is the culprit crumb.

Does anyone know how to zap this tragic reminder of yesterday's errant keystroke (or lack thereof)? Can I erase this UUID without having to once more reformat the drive and copy all the files? Any help is greatly appreciated.

I'm not sure I get the issue. Before you get too much farther let me point out some of my questions.

One is this. "Attempting to install GRUB to a disk with multiple partition labels." Exactly which drive are you trying to install grub on?

Also I don't think you can edit uuid on btrfs yet.

I was installing on /dev/sde (see first line of first quote). Thanks jefro for getting back on this, but I needed to get my computer back up ASAP, and so I'm reformatting and reinstalling once more. Fortunately, everything was backed up. What I'm learning about btrfs is that it is a very sticky filesystem. Once you've made a btrfs RAID, its presence lingers, even after deletion. But btrfs and its capabilities fascinates me, and I'm determined to get this up and running. Thanks, again.

Something learned
 

Zeroed out hard drive (/dev/sde) that I was unable to install grub2 on, and then did the same copying of the partition of its mated drive (/dev/sdb) to sde and this time I was able to install grub2 successfully. Not sure what "multiple blocklists" the warning referred to when I installed it yesterday, but zapping the hard drive with zeroes seems to have done the trick.

This isn't really solved as a problem, but it is resolved.

Thanks for how you got it working.

I was assuming you wanted to install to sda.