Arch Linux

MJBoa

Member

Registered: 2009-03-31

Posts: 32

Dual booting Win7 and Arch with Luks/LVM

Hey all,

I'm kind of stuck about what to do here. I have two main goals. I want to dual boot Win7 and Linux and I want both to be encrypted. I have a laptop and only one hard drive to work with.
At first I was thinking LVM over LUKS. I have LUKS and dm-crypt on my home machine so I know how to handle it. However, I've never really dealt with LVM.
Anyway, it sounded good until I realized that I can only have 4 primary partitions on my HD and with the two required for win7 as well as a third ntfs for storing files between win7 and arch, I'll only have one left for LVM. To me, it now seems like I can't have LVM over LUKS because although GRUB2 can boot from inside LVM, it certainly can't decrypt through LUKS before booting, if I'm not mistaken. So now I'm thinking the best option is LUKS over LVM, while less elegant seems to be my only choice. What does someone think, anyone else dealt with a similar situation?
It's been a while since I've been around Linux so although I'm no stranger, I'm not really as used to it as I once was. Bare with me.
Thanks.

Fungyo

Member

Registered: 2009-04-13

Posts: 42

Re: Dual booting Win7 and Arch with Luks/LVM

Don't forget you can use Extended partitions.

# My setup :-
LVM on LUKS with Grub 1
/boot sda6 (Extended)
LVM Physical Volume sda3 (Primary)
Windows XP on sda1 (Primary)
Could add another Windows NTFS partition as Extended. if needed.

These two pages helped:
https://wiki.archlinux.org/index.php/LUKS
https://wiki.archlinux.org/index.php/LVM

MJBoa

Member

Registered: 2009-03-31

Posts: 32

Re: Dual booting Win7 and Arch with Luks/LVM

True, is it possible to put /boot and an ntfs partition on the same extended partition? can a linux /boot be on an extended partition?

Fungyo

Member

Registered: 2009-04-13

Posts: 42

Re: Dual booting Win7 and Arch with Luks/LVM

I'm guessing /boot can run from ntfs, however probably not as efficiently as if it were running on ext3/4. Mine runs on Ext4.
To add confusion, you only create one Extended partition, all partitions you create within the Extended partition are called Logical partitions. You should be able to create enough Logical partitions for your needs.
Primary/Extended partitions are normally sda1-4 and Logical partitions will usually start from sda5 on modern Sata HDD systems.
For /boot I would create a small 100mb Ext4 Logical partition. This partition cannot be inside LVM nor encrypted when using Grub1.  I'm not familiar with Grub2.