The Disparate Musings of Pixie

Conveniently timed to my previous entry I recently upgraded my laptop to Debian Wheezy. This involved redoing my backup boot drive to contain bootloader updates, so I can detail the process I used.

Partition the USB drive

Use whatever partition manager you're comfortable with. cfdisk, fdisk, gparted, whatever.

# cfdisk /dev/sdb

If you want to use the USB stick on Windows normally, note that Windows will only see the first partition of a thumbdrive. This is great for hiding the fact it's a bootable drive!

# fdisk -lu /dev/sdb
...
Sector size (logical/physical): 512 bytes / 512 bytes
...

Don't start the first partition at the very beginning. Here I've got it started about 4k in. This gap is important: grub will install itself into the gap--if there isn't enough room, grub won't install.

You'll also notice that I've allocated 512MB to what will become /boot (sdb2). This is serious overkill, but also means I don't have to be particularly cautious about uninstalling old kernel versions to avoid running out of room.

Format the Partitions

Naturally, we should format these partitions:

# mkfs -t vfat /dev/sdb1
# mkfs -t ext3 /dev/sdb2

Install grub

Then mount our soon-to-be /boot drive into /boot (if you're familiar with grub-install, you can mount it elsewhere):

# mount /dev/sdb2 /boot

And install grub:

# grub-install /dev/sdb

Naturally, your next step should be to test that it boots. And maybe even test that it appears as a normal thumbdrive on a Windows computer.

When Doing a Fresh Install

NB: This is from-memory. I have not done this recently.

If you're doing a fresh install, partition the USB drive from another computer. Make sure the thumbdrive is plugged in during the install process, and when configuring drive partitions and directory locations, simply select /dev/sdb2 (or whichever is appropriate for the USB drive's second partition) as the device on to which to put /boot.

If you happen to be lax in upgrading software, you might have an older version of magit where if M-x magit-status is allowed to initialize a git repository where none was before, it has a tendency to create said repository in the directory '$HOME/repo/~/repo'[1].

If this happens, and one wishes to remove that annoying and non-useful '~' directory, do not, I repeat, do not run the command:

rm -r ~

That is bad. Remember shell expansion! You need to quote the tilde:

rm -r '~'

But also note that even the latter should not be done within eshell, as it seems to be intent on expanding the tilde anyway. Use a real shell.

Also, always do `ls $dir` before you do `rm $dir`, just to double-check what you're deleting. Even if you're sure, check anyway.

Because otherwise, you might accidentally delete your home directory.

On the bright side, I can now confirm my backups work.

[1] see bug 383