Slackware 14 USB Install

Okay, its been quite a while since I've shared anything.

Credit for the following post goes to Gareth Lowe, a LQ newbie (although the level of advice given in this post proves Gareth is anything BUT).

Unfortunately I didn't have much computer access for about oh a good 5 months. This was due to several reasons, although in retrospect I should've taken the initiative to hit up the local goodwill's in search of a barton amd system (a good 10 years old now, but still reliable in my opinion).

Anyways fast foward to April 14 2013 and I discover Slack14 has been released. There was an extra lappy sitting around my folks house, and not wanting to permenantly alter the HD data (and having no storage resources to perform a backup), I thought I'd go ahead and instal Slack14 on a good ol thumb drive. I briefly considered using Slax (which I've used before, and is quite good), although considering Slax is based on 12.0, I wouldn't settle until I had the real enchilada.

If I was in practice, I'm sure I could've figured this out. Although, I wasn't able to immediately, and I give a many humble thanks to Gareth for sharing this advice.

Now, onto the good stuff!

INSTRUCTIONS:

OK yall, a quick rundown on how I setup a usb HDD with a bootable Slackware 14 install today.

Firstly, I installed the base system from the CD, with my partition table looking a little something like this..

/dev/sda1   *     63                 1558304         779121           83  Linux                       /boot
/dev/sda2         1558305        9365894        3903795          82  Linux swap              swap
/dev/sda3   *     9365895       204684164     97659135       83  Linux                       /
/dev/sda4          204684165   1953519615   874417725+   7  HPFS/NTFS/exFAT  /store

Now during the install I chose the simple LILO install option, into the MBR of /dev/sda.

After that I modified my initrd tree, firstly by deleting it, located at /boot/initrd-tree, and then by running mkinitrd, which will give us a fresh tree and populate it. Now to get a working initrd image to bring up the usb disk on boot, first I had to modify /boot/initrd-tree/wait-for-root and set the value to something in seconds to allow the drive time to come up once the modules are loaded. I set mine to 15. Next I modified the fstab to only reference UUIDs when mounting the disks, as If you are using this on different machines, you may find the disk moves locations depending on how many disks are in said machine, ie : /dev/sda if singlular, or first drive (unlikely, given USB) becomes /dev/sdb or c, if detected after others. This way the drive is always referenced correctly and you dont get kernel panics. You can get the UUID of your partitions by ‘blkid’.

My fstab is as follows:

UUID=af7efa55-2f37-415a-b131-130d2accbd5d        swap             swap       defaults         0   0
UUID=ddee4a6a-900d-494e-9573-acb6fd371faf        /                    ext4         defaults         1   1
UUID=dac53074-92d8-4fb1-abc9-0bd0f0631102       /boot             ext2        defaults         1   2
UUID=3E58608D586045AD        /store        ntfs        fmask=111,dmask=000 1   0
#/dev/cdrom      /mnt/cdrom      auto        noauto,owner,ro,comment=x-gvfs-show 0   0
/dev/fd0             /mnt/floppy       auto        noauto,owner         0   0
devpts               /dev/pts            devpts     gid=5,mode=620   0   0
proc                  /proc                 proc        defaults                   0   0
tmpfs                /dev/shm          tmpfs       defaults                   0   0

Next I built my initrd image using the command ‘mkinitrd -s /boot/initrd-tree -k 3.2.29-smp -m ehci-hcd:uhci-hcd:usb-storage -f ext4  -o /boot/initrd.gz’. You will note the modules we are placing into the image, these will be loaded and allow the drive to be initialised, and the root fs duties to be handed off to it. Change the variables for kernel and filesystem as needed.

Lastly, I configured and reinstalled LILO. Again, like the example above, we want to modify it to only use UUIDs as reference, and to add in the lines for our initrd. Make sure you place the initrd line above the root line when configuring, it denotes hierachy.

My lilo.conf entries, dont forget to change the boot line to the target HDD.

boot = /dev/sdc
image = /boot/vmlinuz
initrd = /boot/initrd.gz
root = “UUID=ddee4a6a-900d-494e-9573-acb6fd371faf”
label = Slack14
read-only

Lastly, run ‘lilo -v’ to commit the whole thing to the MBR.


Sources:

1. Linuxquestions.org: http://www.linuxquestions.org/questions/slackware-installation-40/slackware-14-usb-hdd-install-4175457861/

2. Blogger.com: http://unsoundadvice.wordpress.com/2013/04/12/slackware-14-usb-hdd-install/

Notes:
a. Initrd:
 i.   Del initrd tree: /boot/initrd-tree
 ii.  run mkinitrd
 iii.  modify /boot/initrd-tree/wait-for-root to 15s

b. Use UUID's in /etc/fstab to identify partitions

c. Create initrd via the following command:
mkinitrd -s /boot/initrd-tree -k 3.2.29-smp -m ehci-hcd:uhci-hcd:usb-storage -f ext4  -o /boot/initrd.gz

It is important to include the ehci-hcd, uhci-hcd, and usb-storage modules, as these modules are the drivers which allow the system to load usb storage devices upon boot, and make it the root filesystem.

d.  Modifly Lilo.conf as in example above. Make sure to denote root partition by UUID, and include the initrd.gz file in the configuration to ensure loading the aforementioned modules.

I am using this to boot off of my 32gb verbatim thumb drive. And its reasonably fast! (Excluding the 15s wait.)

- Slug