Without using the script solution, you can just as easily: a) power down your device, b) remove the usb with Arch arm on it, and c) plug it into another computer running Arch arm and then following the steps detailed well here (
https://wiki.archlinux.org/index.php/Change_root) to mount and chroot into your system. Those steps are (where /dev/sdx1 is your usb device detected):
$this->bbcode_second_pass_code('', '# mount /dev/sdx1 mnt/YOUR_MOUNT_DIR
# arch-chroot /mnt/YOUR_MOUNT_DIR')
After you have successfully chrooted into your USB drive alarm system, you can then just do the downgrade for packages systemd and/or the kernel as necessary. In my case, on a PogoPlug v4 I needed to downgrade the kernel as well back to 3.19 as the 4.0 kernel is noted as introducing a regression that affects USB 3.0 (which pogoplug v4 has)--and which messed up access to mounted drives. So in my case I ran these commands:
$this->bbcode_second_pass_code('', '# cd /var/cache/pacman/pkg/
# pacman -U linux-kirkwood-3.19.3-1-arm.pkg.tar.xz linux-kirkwood-headers-3.19.3-1-arm.pkg.tar.xz systemd-218-2-arm.pkg.tar.xz systemd-sysvcompat-218-2-arm.pkg.tar.xz')
In the case where older versions of systemd systemd-sysvcompat don't exist you can grab them from these URLs (and then try pacman -U .... to downgrade again):
$this->bbcode_second_pass_code('', 'wget http://rollback.archlinuxarm.org/packages/s/systemd-sysvcompat/systemd-sysvcompat-218-2-arm.pkg.tar.xz
wget http://rollback.archlinuxarm.org/packages/s/systemd/systemd-218-2-arm.pkg.tar.xz
')
Finally, you can make the change that @kurter noted:
$this->bbcode_second_pass_quote('', 'c')hange your /etc/pacman.conf file to add this line
nano /etc/pacman.conf
IgnorePkg = linux-kirkwood linux-api-headers libsystemd systemd systemd-sysvcompat
Note* (I believe there is one typo in @kurter's original post.... the second ignored package should be
). Like so:
$this->bbcode_second_pass_code('', ' IgnorePkg = linux-kirkwood linux-kirkwood-headers libsystemd systemd systemd-sysvcompat ')
You should then be able to umount the usb drive and exit the chroot, plug the usb drive back into your original device, and then boot back up. Basically, there is
to have to do a full re-install from scratch and lose all your settings or files incase your backup methods are not very adequate. If you have a latest backup image you just want to easily restore instead...great. If not, doing this fix should take 15 minutes or less and get you back up and running as you were before the updates that ruined your day
.
Hope it helps someone who upgraded and inadvertently lost network ability and also usb 3.0 proper usage!
.