Using a USB Stick to Install Slackware-Current

Slackware stable releases have a well earned reputation for being “rock solid”. (Stable Slackware releases have a version number associated with them, i.e. “Slackware 14.2”)

In addition to stable releases, Slackware has a version called “Slackware-Current”, which is where active development happens for the next stable release of Slackware. This can be confusing: despite its name, Slackware-Current is usually not what you want.

Choosing to use Slackware-Current means that you get bleeding edge software, but it has not be as thoroughly tested as a stable release. There is no expectation that Slackware-Current will be “rock solid”. It generally is. But sometimes it isn’t. It’s under active development.

As I write this, the current stable release of Slackware is Slackware 14.2, which was released on June 30, 2016. I’ve seen the occasional post out there on the internet that refers to Slackware-Current as “Slackware 15”.

I try to avoid Slackware-Current, if I can. Sometimes, though, it can’t be avoided — especially if you’re dealing with relatively new hardware specs.

For example, Slackware 14.2 was released with a version of the Slackware installer that has version of the LILO bootloader that did not yet have support for NVMe solid state drives (SSD). But a patch was submitted to include support for NVMe in LILO and then included in Slackware-Current back in 2018. If you happen to have a computer that only has an NVMe SSD, and you want to install Slackware on it, your best option right now is to install Slackware-Current. Here’s how I do it, using a USB stick instead of a DVD.

Mirror Slackware-Current

Eric Hameleers wrote this script to help you create your own local Slackware mirror back in 2009 and it still works great today: http://www.slackware.com/~alien/tools/mirror-slackware-current.sh

Let’s try it out.

Download mirror-slackware-current.sh :

wget http://www.slackware.com/~alien/tools/mirror-slackware-current.sh
chmod +x mirror-slackware-current.sh

The script expects that the following directory exists:

mkdir -pv slackware64-current

Then:

ARCH=x86_64 \
./mirror-slackware-current.sh \
-l . \
-X none \
-o NONE

ARCH=x86_64 tells the script to mirror the 64-bit version of Slackware-Current.

-l . tells the script to create the mirror right here in our current directory where we created the directories slackware64-current and slackware64-current-iso .

-X none tells the script to not filter any parts of the mirror — essentially, to mirror everything.

-o NONE tells the script to skip create an installer DVD ISO file when it finishes creating a local mirror. (This is a a brilliant featurein mirror-slackware-current.sh , but we don’t need it for this. If we had created an ISO file, mirror-slackware-current.sh expects that a directory named slackware64-current-iso exists in addition to the one we created.)

Fun fact: mirror-slackware-current.sh can mirror stable Slackware releases with the -r flag, as well. For example, adding -r 14.2 ought to give us a mirror of Slackware 14.2.

Burn Slackware-Current to a USB Stick

Let’s burn the Slackware installer to our USB device at /dev/sda .

First, we need to know which file represents our USB device.

I use this technique to make sure I know which device my Linux operating system thinks my USB drive is:

sudo su
watch 'dmesg | tail'
# insert USB device

In my case, it’s clear to see that my Linux operating system recognizes my USB device as /dev/sda when I plug it in. In your case, it may be something else. If it is, you’ll have to adjust the remaining commands accordingly.

Optionally, at this point, I sometimes choose to wipe my USB drive, before I burn the Slackware to it:

dc3dd wipe=/dev/sda verb=on

I use dc3dd instead of just dd because dc3dd offers the verb=on flag, which gives me an idea about the progress its making as it runs. I find the wipe= flag handy as well.

On to the main event.

Again, Eric Hameleers wrote a great script called usbimg2disk.sh, which has shipped with the Slackware installer for years. As a result of mirroring Slackware-Current, we should have a copy of it in slackware-current/usb-and-pxe-installers/. Let’s see it in action:

./slackware64-current/usb-and-pxe-installers/usbimg2disk.sh \
-u \
-f \
-s ./slackware64-current \
-i slackware64-current/usb-and-pxe-installers/usbboot.img \
-o /dev/sda

-u tells the script to run “unattended” (i.e. don’t ask me any questions, assume defaults are fine, etc)

-f will format the drive specified by the -o flag.

-s tells the script where the root of our collection of Slackware packages is.

-i tells the script where the usbboot.img binary lives.

-o tells the script which device to prepare as a Slackware installer. In my case, it’s /dev/sda.

When I run the script in this way, I see the following output:

--- Formatting /dev/sda with VFAT partition label 'USBSLACKINS'...
--- Available free space on the the USB drive is 15102536 KB
--- Required free space for installer: 54516 KB
--- Copying boot files to the USB drive...
--- Copying Slackware package tree to the USB drive...
--- Syncing I/O...
--- Unmounting volumes and deleting temporary files...
--- Making the USB drive '/dev/sda' bootable...
--- Done.

That’s it! We’re done!

You should now be able to reboot a machine with this USB stick plugged in, and install Slackware-Current the way you’d normally install Slackware.

Bonus Tips

While usbimg2disk.sh is running, the following line takes quite a while to complete, in my experience:

--- Copying Slackware package tree to the USB drive...

When I first started using this script, it sat idle long enough at this point that I thought something may have gone wrong. In this case, however, no news is good news.

Still, I prefer a bit more information about the progress being made. When usbimg2disk.sh gets to this point, all it is doing is copying the Slackware packages we just cached locally with mirror-slackware-current.sh to our USB drive at /dev/sda . So, to keep an eye on the script’s progress, I pop open another terminal window to…

1. Determine the ballpark number of Slackware packages that we ought to copy to /dev/sda :

find slackware64-current/slackware64/ | wc -l

2. Keep an eye on the number of Slackware packages actually transferred to /dev/sda :

MY_MNT=$(mount | grep sda | awk '{print $3}')
watch "find $MY_MNT/slackware64-current/ | wc -l"

Note that the number that I see from 2 is a few hundred more than what I see in 1. That’s a good enough ball park for me. I just want to know that the script is progressing and have a relative idea about how close it is to done.

Also, the following line takes a while to complete, for me:

--- Syncing I/O...

If usbimg2disk.sh reaches this point, though, I know that everything went well. I don’t try to measure progress, in this case. I just walk away from the computer for a few minutes. Usually by the time I come back it’s done.