Skip to content

Make the external root helper script work with modern Rasberry Pi OS #14

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 3 commits into
base: master
Choose a base branch
from
Open

Make the external root helper script work with modern Rasberry Pi OS #14

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
8599740
Removed method for getting PARTUUID that nolonger works, this informa…
benjamin-nose Aug 29, 2022
04d6b55
PARTUUID is now refered to in /boot/cmdline.txt by default, updated t…
benjamin-nose Aug 29, 2022
09a77d0
Fixed method for commenting out the old root partition that nolonger …
benjamin-nose Aug 30, 2022
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
23 changes: 10 additions & 13 deletions adafruit-pi-externalroot-helper
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -111,17 +111,12 @@ info "fs id" "Getting UUID for target partition"
eval `blkid -o export "${target_partition}"`
export target_partition_uuid=$UUID

info "fs id" "Getting Partition unique GUID for target filesystem"
# Ok, so the only way I was able to get this was using gdisk.
# I don't quite understand the different between this value and
# the one you can get with blkid and tune2fs (which seem to give
# the same thing). Nevertheless, this seems to be necessary to
# get a value that can be used in cmdline.txt. I think it's a
# GUID specifically for the GPT partition table entry.
export partition_unique_guid=`echo 'i' | sudo gdisk "${target_drive}" | grep 'Partition unique GUID:' | awk '{print $4}'`
info "fs id" "Getting Partition unique PARTUUID for target filesystem"
#This value is also part of the blkid info
export partition_unique_partuuid=$PARTUUID

info "fs id" "Target partition UUID: ${target_partition_uuid}"
info "fs id" "Partition unique GUID: ${partition_unique_guid}"
info "fs id" "Partition unique PARTUUID: ${partition_unique_partuuid}"

info "fs copy" "Mounting ${target_partition} on /mnt"
mount "${target_partition}" /mnt
Expand All @@ -131,16 +126,18 @@ info "fs copy" "This will take quite a while. Please be patient!"
rsync -ax / /mnt

info "boot config" "Configuring boot from {$target_partition}"
# rootdelay=5 is likely not necessary here, but seems to do no harm.
#rootwait is already in the file and is sufficient
cp /boot/cmdline.txt /boot/cmdline.txt.bak
sed -i "s|root=\/dev\/mmcblk0p2|root=PARTUUID=${partition_unique_guid} rootdelay=5|" /boot/cmdline.txt
sed -i "s|root=PARTUUID=\S\+ |root=PARTUUID=${partition_unique_partuuid} |g" /boot/cmdline.txt

info "boot config" "Commenting out old root partition in /etc/fstab, adding new one"
# These changes are made on the new drive after copying so that they
# don't have to be undone in order to switch back to booting from the
# SD card.
sed -i '/mmcblk0p2/s/^/#/' /mnt/etc/fstab
echo "/dev/disk/by-uuid/${target_partition_uuid} / ext4 defaults,noatime 0 1" >> /mnt/etc/fstab
#comment out old root entry from fstab (this approach respects previous comments)
sed -i -E 's|(^[^\#]*\s\/\s[^\#]*)|#\1|g' /mnt/etc/fstab
#add new root entry
echo "PARTUUID=${partition_unique_partuuid} / ext4 defaults,noatime 0 1" >> /mnt/etc/fstab

info "boot config" "Ok, your system should be ready. You may wish to check:"
info "boot config" " /mnt/etc/fstab"
Expand Down