Arch Linux

the_nforcer

Member

From: Toronto, Ontario, Canada

Registered: 2014-02-01

Posts: 8

Multi boot (Arch + Ubuntu + Windows) multiple encrypted disks [SOLVED]

Hi there, this is my first post in the forums. Usually the amazing Arch Wiki answers my questions but I have finally ran into a couple issues (related to the same problem) and was hoping someone would be kind/knowledgeable enough to help.

Basically my goal is to have Arch & Ubuntu on my SSD with independent encrypted LVM partitions, while using a secondary HDD as a shared encrypted LVM for swap, /home and /games. I will also have a small unencrypted Windows 7 partition on my SSD. Note I'm not using UEFI and all operating systems will be 64-bit. I already know how to setup Arch using dm-crypt & LVM. Also, I specifically want to enter two passwords on boot for each distro, one for root and one for the shared /home.

Here is the desired hard disk & partition setup..

256 GB SSD (MBR)
  >  60 GB - Windows 7 (NTFS partition, unencrypted)
  >  75 GB - Ubuntu 14.04 (encrypted LVM for / and /usr | ext4 or XFS)
  >  ~100 GB - Arch Linux (different encrypted LVM for / and possibly /usr & /var  |  ext4 or XFS)
  >  ??  256 MB to 1024 MB - /boot   ??? shared or separate per OS???

750 GB HDD (GPT, Shared Drive, 1 encrypted LVM partition)
  >  24 GB - Shared SWAP for hibernation (I have 24GB of RAM)
  >  150 GB - Shared /home partition  |  btrfs or xfs
  >  ~515 GB - Shared /games partition for STEAM files & games  |  ext4

First I installed Windows 7. Next, I installed Ubuntu on the first encrypted LVM partition & also created the 750GB encrypted LVM partition for /home, /games and SWAP. I made an unencrypted /boot (ext2) on my SSD with 250 MB. Installed GRUB to the MBR. Everything worked ok, dual booting between Ubuntu and Windows worked fine.

The issues I had were after Installing Arch. I used cryptsetup to make the Arch encrypted LVM partition, then activated the 750GB shared encrypted LVM created by Ubuntu. I mounted all partitions but didn't format the shared ones. I used the same /boot partition for both distros, but didn't format it. Again, I installed GRUB to the MBR hoping it would detect all operating systems over again. Finished the remaining install process, everything seemed to be fine until I rebooted...

Here are my issues...

1)  Only Windows and Arch show up in GRUB, Ubuntu is not listed anymore. Should I be using two independent /boot partitions for each distro, or is one shared /boot ok? Perhaps I just have to manually add Ubuntu back to the GRUB menu and point it to the correct volume group? Or do you think I somehow messed up the Ubuntu install completely this way?

2)  Arch will not load any partitions from my 750GB shared drive. I heard you have to hack the encrypt flag or something if you have multiple disks with multiple encrypted LVM partitions? Does anyone have experience with this?

Sorry for the long post, but I can't seem to find information related to my specific needs. I don't necessarily have to use GRUB, if you guys know a way to achieve this with syslinux or LILO. Any help would be greatly appreciated. Thanks!

Last edited by the_nforcer (2014-07-10 08:22:10)

clfarron4

Member

From: London, UK

Registered: 2013-06-28

Posts: 2,163

Website

Re: Multi boot (Arch + Ubuntu + Windows) multiple encrypted disks [SOLVED]

1) If it were me, I'd use two separate /boot partitions to avoid conflicts between GRUB configurations.

Remember that Ubuntu updates GRUB configurations on every kernel update, where Arch doesn't.

EDIT: Actually, you might be able to share /boot if you let Ubuntu manage bootloaders and leave Arch without one (so have the GRUB package installed in Arch, but don't set it up)/

2) I haven't a clue.

Last edited by clfarron4 (2014-06-07 13:00:32)

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the_nforcer

Member

From: Toronto, Ontario, Canada

Registered: 2014-02-01

Posts: 8

Re: Multi boot (Arch + Ubuntu + Windows) multiple encrypted disks [SOLVED]

Thanks for the reply, I decided to split the /boot into two separate partitions to hopefully minimize future issues. Ubuntu is on the GRUB menu now and working without any issues. Pretty sure last time I forgot to open & mount the Ubuntu lvm container with root as well, so that's probably why GRUB didn't pick it up initially. Should have been obvious to me...

I got Arch to boot with my crazy setup finally! For the secondary hard drive with /home, /games & swap I was using a wrong format in /etc/crypttab and /etc/fstab for encryption. I was defining each lvm container instead of the partition /dev/sdb for crypttab. For fstab, I had to switched from using UUID for the file system to the actual /dev/mapper mounts.

So all 3 operating systems will boot now, my issues have been solved. I just hope future updates don't break GRUB or anything.

Last edited by the_nforcer (2014-06-08 06:56:48)