[SOLVED] About to install Arch. Need advice on LVM, <REDACTED>

Splooshie123 · 2012-03-29 07:35:09

EDIT: This video explained most of what I wanted to know: http://www.youtube.com/watch?gl=US&v=69X9ZYA41xU

Hey guys (and girls), I'm switching over from Ubuntu to Arch Linux. I got a few questions concerning LVM, swap partitions and filesystem types.

I'm planning to dual-boot Arch and Mac OS X (I'm replacing Ubuntu). I'll be mounting '/', '/boot', '/var' and '/home' to their own partitions (and maybe a swap partition) so I'll obviously need LVM.
I read that I can put /boot in a logical partition if I use GRUB2 as a bootloader (was planning to do that anyway), so I will.

What I want is to create the partition scheme mentioned below within an extended partition (LVM) and then just choose the mount points during installation.

The problem is that the wiki is a bit vague about some aspects of LVM (particularly creating partitions within the extended partition). Can anyone help me with the exact commands for the following setup:

Mount point - Size - Format

/boot - 100MB - ext2 (I read /boot doesn't need journaling)
/ - 20GB - ext4
/var - 12GB - ReiserFS
swap - 4GB - Linux Swap
/home - The rest (about 84GB) - ext4

I have OS X on this hard drive so please no commands that wipe the drive (I'll resize the OS X partition using Disk Utility on the install CD). Also, if you can suggest better formats for the different partitions (and why a different format would be better) that would be great.

Now, about the swap partition. I have 4GB of RAM on the MacBook Pro and I'd like to be able to hibernate so is 4GB RAM reasonable? (I'm betting my memory usage will probably never reach that much on Linux except in extreme cases like memory leaks)

Thanks.

PS: The reason I want to be able to hibernate is because my mom borrows my mac often. She is barely computer-literate (had to ask me how to copy-paste files) so I doubt she would be able to use Arch. Because of this, I have to reboot to OS X when she needs to use it and I would like to be able to save the state of Arch while she reboots into OS X (I'm assuming since hibernation is save to disk, meaning swap, I should be able to reboot to a different OS then come back to Arch and continue where I left off).

Last edited by Splooshie123 (2012-04-03 02:38:12)

swanson · 2012-03-29 08:10:38

I only have one small advice; if you want to use for example e4rat as a boot accelarator, it only works on ext4. More on e4rat; https://wiki.archlinux.org/index.php/E4rat
e4rat really is magic!

jasonwryan · 2012-03-29 08:18:08

Splooshie123 wrote:

Can anyone help me with the exact commands for the following setup

We don't really work that way here.

If you find the wiki article is not clear (it works for most people), then ask a specific question about what isn't clear. If you expect someone to just tell you what to do, you're not going to enjoy running Arch.

Splooshie123 · 2012-03-29 08:19:08

Thanks swanson. I'll check it out. But what I don't understand is it says ext4 only what do they mean? Do all partitions have to be ext4 or just those needed for booting?

Ok, so I guess its time to fire up Virtualbox again. I'll check the manuals for the commands in the wiki. (Thanks for the quick replies. At ubuntuforums.org I had to wait a few hours or not get an answer at all)

I still need to adjust to the new forum community.

Last edited by Splooshie123 (2012-03-29 08:26:21)

swanson · 2012-03-29 08:25:07

Are you asking about e4rat? If so, all partitions involved in bootiing needs to be ext4. Especially when autologin and boot reads from /boot, / , /home/user and possibly /var as well. Sorry to lead you astray, but e4rat really is recommendable, mostly though when autologin.

Splooshie123 · 2012-03-29 08:31:26

Err, I don't do autologin. I log in manually. (at least everything-has-a-gui-Ubuntu hasn't made me that lazy! )

swanson · 2012-03-29 10:26:58

everything-has-a-gui-Ubuntu

- That's a good one! I use to use Ubuntu too.
Well, if autologin isn't your method then e4rat might not be that important for you. It does speed up the boot bedfore login, but the heaviest apps are often started after boot.

Splooshie123 · 2012-03-30 00:58:53

@swanson: I don't really need a boot accelerator yet since Arch boots in slightly under 9 seconds on a virtualbox LiveCD and maybe about 12 seconds for a fully installed system in VirtualBox.

Ok, so I saw this video on youtube: http://www.youtube.com/watch?gl=US&v=69X9ZYA41xU

That cleared up nearly everything. Macs are already GPT and already have their own boot partition (so I won't create a new one as mentioned in the video) and I'll replace the grub-bios with the grub-efi as described on the wiki.

What I don't fully understand is which file should I edit to add extra configuration options for GRUB2 entries? In the video, he edited 40_custom but that's for custom menu entries. Can't I just edit the the 10_linux file? Will it break the system? EDIT: Nevermind. 10_linux is a script. How do I add default options (insmod lvm2 and set root=(lvm_group_name-lvm_logical_boot_partition_name)) for linux grub entries?

I think I need to add this stuff to the /etc/default/grub. Where in the file do I add them?

I cannot test this with VirtualBox because I can't get Internet working with the Guest system (any guest system) so I can't install GRUB2 in my virtual test system.

Last edited by Splooshie123 (2012-03-30 01:54:39)

Splooshie123 · 2012-03-30 03:28:11

Sorry for the double post. (the etiquette page didn't say anything restricting it though)

I'm trying to get these options by default, right?

insmod lvm2
set root=(Arch_Linux-boot)

By reading the online GRUB2 docs (my local version seems to be corrupted) I can load the "lvm2" module by specifying GRUB_PRELOAD_MODULES="lvm2" in /etc/default/grub.

So what's left is how do I set the second command (see code)?

Do I have to add "set root" to the "GRUB_CMDLINE_LINUX_DEFAULT="? Again, I am asking because I cannot test this since my virtual machine can't connect to the Internet.

EDIT: Ok, so I was able to install Arch. Now I have problems with getting GRUB2 to work. I posted a new thread.

Last edited by Splooshie123 (2012-03-31 08:37:27)

Arch Linux

#1 2012-03-29 07:35:09

[SOLVED] About to install Arch. Need advice on LVM, <REDACTED>

#2 2012-03-29 08:10:38

Re: [SOLVED] About to install Arch. Need advice on LVM, <REDACTED>

#3 2012-03-29 08:18:08

Re: [SOLVED] About to install Arch. Need advice on LVM, <REDACTED>

#4 2012-03-29 08:19:08

Re: [SOLVED] About to install Arch. Need advice on LVM, <REDACTED>

#5 2012-03-29 08:25:07

Re: [SOLVED] About to install Arch. Need advice on LVM, <REDACTED>

#6 2012-03-29 08:31:26

Re: [SOLVED] About to install Arch. Need advice on LVM, <REDACTED>

#7 2012-03-29 10:26:58

Re: [SOLVED] About to install Arch. Need advice on LVM, <REDACTED>

#8 2012-03-30 00:58:53

Re: [SOLVED] About to install Arch. Need advice on LVM, <REDACTED>

#9 2012-03-30 03:28:11

Re: [SOLVED] About to install Arch. Need advice on LVM, <REDACTED>

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