Boot & USB setup

Install Slax on USB or disk

The Slax ISO includes a graphical installer. It can prepare a USB drive or add Slax alongside an existing operating system on a supported internal disk. The installer copies the Slax files and sets up booting for you.

Open Slax Installer

• Windows: Double-click the downloaded ISO to open it in File Explorer. Open the slax folder and run slax-install.exe as administrator.
• Linux: Mount the ISO and run slax-install-linux from its slax folder as root.

Choose where to install

If the installer asks for an ISO, select the Slax ISO file you downloaded. Then choose your destination drive or partition and review the installation plan before confirming. On supported layouts, the installer keeps your files and adds Slax as a boot choice alongside the existing system.

Leave Erase entire selected disk unchecked to preserve existing data. Turning it on deletes all partitions and files on the selected physical disk, including other drive letters on that disk.

Boot your computer

Restart and open your computer’s boot-device menu. The key is often F11, F9, F12 or Esc; check the startup screen or the computer’s instructions. Choose the USB drive or select Slax from the boot menu on your internal disk. Slax includes a signed UEFI bootloader and kernel, so Secure Boot can stay enabled on compatible systems.

Slax on CD/DVD

Burn the ISO using your disc-burning software’s Burn image option. The ISO is a complete disc image; copying the ISO file onto an ordinary data disc will not create a bootable Slax disc. Either a CD or DVD with enough capacity can be used.

Choose the optical drive in the computer’s boot menu. A disc is read-only, but you can still keep a persistent session on another writable drive by choosing Choose session during startup.

Slax boot options

The Slax logo appears with a five-second countdown. Press Enter to start the default option immediately, or Esc to open the full boot menu. Use the arrow keys to highlight an option and Enter to start it.

• Resume previous session automatically picks up your most recently used session across the available writable drives. If there is no saved session and the boot medium is writable, Slax creates an Initial session.
• Choose session during startup opens the session chooser so you can pick a saved session or create a new one.
• Run Slax from RAM (copy to ram) copies Slax into memory and starts a temporary session. You can remove the boot medium once Slax is running.
• Start Slax in text mode only (no desktop) starts at a text console for command-line work.

Select session

The chooser shows each saved session’s name, drive, date and size. Select Start a new session to pick a writable drive and name a new session. With an existing session highlighted, press F4 to duplicate it on the same drive or F6 to rename it.

Cancelling a name or drive selection returns to the chooser. Press Esc in the chooser to continue without saving changes. Once Slax is loading, Esc shows the boot log behind the splash.

Persistent changes

A persistent session keeps your installed applications, settings and files for the next boot. Choose one of the session options above to use it. Without a writable selected session, system changes remain in memory and disappear when you shut down. A writable USB alone is not a guarantee of persistence; the selected boot option and session matter too.

Sessions have friendly names in the chooser, while their storage directories keep numeric identifiers such as /slax/changes/1/ and /slax/changes/2/. The name is stored in session.txt alongside changes.dat for DynFileFS sessions, or in boot/session.txt inside a native session. A session may live on another drive even when Slax itself starts from a CD, ISO or read-only USB system partition.

On a native Linux filesystem

On a suitable filesystem such as ext4, Slax stores the session directly in its directory. OverlayFS keeps your changed files in a changes/ subdirectory and its internal working data in workdir/. Available drive space and filesystem limits determine how much you can save.

On FAT and similar filesystems

Slax uses DynFileFS to create a virtual disk from ordinary files named changes.dat, changes.dat.0 and further parts inside the session directory. An XFS filesystem inside that virtual disk provides the Linux permissions and metadata that FAT cannot store itself.

The data files grow as blocks are written; the full virtual capacity is not reserved in advance. The default limit is 16,000 MiB. To increase it, add a boot parameter such as perchsize=32G, which sets a 32,000 MiB limit. Once enlarged, the stored capacity is remembered and the parameter can be omitted at later boots. Actual free space on the drive still limits what can be written.

For a backup, copy the entire numbered session directory while that session is not running. Keep all its changes.dat* parts together. changes.dat alone is only the storage metadata. See how DynFileFS works for an illustrated explanation.

Open the files from an inactive FAT-backed session

Boot without persistence, or select a different session. Work with a copy of the inactive session directory; do not mount the current session a second time. Replace the example path below with the copied changes.dat file. Both mount directories must be empty.

mkdir -p /mnt/session-storage /mnt/session
/run/initramfs/bin/@mount.dynfilefs -f /path/to/session/changes.dat -m /mnt/session-storage
mount -t xfs -o loop,ro,norecovery /mnt/session-storage/virtual.dat /mnt/session

The first mount exposes DynFileFS’s virtual.dat. The second opens its XFS filesystem read-only. Your modified Linux files are under /mnt/session/changes/; this is the writable layer’s contents, not a complete copy of the base Slax system. When finished, unmount in reverse order:

umount /mnt/session
umount /mnt/session-storage

The current DynFileFS cannot open the older format 400 storage. To move those files, open the old session with the version that created it, then copy the files into a new session.

Shutting down Slax safely

Choose a power action in the launcher’s Session category, or use poweroff or reboot in a terminal. Wait for shutdown to finish before removing drives used by Slax.

The boot drive can still supply system files, and a persistent session may still be writing to its own drive. Slax releases those mounts at the end of shutdown. Also unmount any other drive before unplugging it if you opened files there.

Running from memory

Choose Run Slax from RAM (copy to ram) to copy the Slax data into memory during startup. It takes a little longer to start, but the system then reads its modules from RAM instead of the boot medium.

The supplied RAM entry does not enable persistence. After startup releases the boot medium, it can be removed. Changes to the live system disappear at shutdown, so save documents you want to keep onto another drive or remote storage.

You need RAM for the complete Slax image as well as the running desktop and applications. The 512 MiB ISO size is not a minimum RAM requirement; a browser needs additional working memory. If you add persistence to a custom RAM boot, its storage must remain connected while in use.

Cheatcodes for Slax

Boot parameters, also called cheatcodes, change how Slax starts. Press Esc during the countdown, select an entry in GRUB and press e. Add your parameters to the end of the line beginning with linux. Press Ctrl+X to boot the edited entry. These edits apply to that boot only.

Separate parameters with spaces. Device names in the examples are placeholders for your own drives. The manual page man bootparam describes additional general Linux kernel parameters.