What is the difference between the new LTSP and LTSP5?

Updated

The new LTSP is a from-scratch redesign and rewrite published in 2019 by alkisg, built to support modern technologies such as systemd, updated desktop environments, Wayland, and UEFI. The old version is now called LTSP5 and sits in minimal maintenance mode. Only the new version is actively developed, so new deployments should use the new LTSP.

The two versions at a glance

Dimension New LTSP LTSP5
Origin Redesigned and rewritten from scratch in 2019 by alkisg The original implementation, now renamed LTSP5
Development status Actively developed Minimal maintenance mode
Technology support systemd, updated desktop environments, Wayland, UEFI, and similar modern stacks Predates those technologies
Choice for new installs The version to use Not the target for new work

Why the rewrite happened

The project states the rewrite was done specifically to support new technologies like systemd, updated desktop environments, Wayland, and UEFI. Those are not cosmetic differences: a boot and session stack built around systemd and Wayland behaves differently from one designed before them, which is why the project chose a clean rewrite rather than patching the old codebase.

What both versions share

The core idea is unchanged. LTSP netboots LAN clients from a single template installation that lives in a virtual machine image, a chroot on the LTSP server, or the server root itself (/, "chrootless"). Maintaining tens or hundreds of diskless clients is then as easy as maintaining a single PC.

The new LTSP automatically configures and uses this toolchain:

  • iPXE — network boot loader that shows the initial client boot menu and loads the kernel/initrd.
  • dnsmasq or isc-dhcp-server — DHCP server that assigns IPs to clients, or a ProxyDHCP server when another DHCP server (for example a router) is already in use.
  • dnsmasq or tftpd-hpa — TFTP server that sends ipxe/kernel/initrd to clients.
  • dnsmasq — optional DNS server for caching or blacklisting.
  • mksquashfs — creates a compressed copy of the template image/chroot/VM used as the client root /.
  • NFS or NBD — serves the squashfs image over the network.
  • tmpfs and overlayfs — make the squashfs image temporarily writable per client, similar to live CDs.
  • NFS or SSHFS — provides access to the user's /home directory on the server.
  • SSH, SSHFS, or LDAP — authenticates users against the server.

Which one should you use

Choose the new LTSP if you are starting a deployment, or if you need systemd, current desktop environments, Wayland, or UEFI boot. Choose LTSP5 only if you are maintaining an existing LTSP5 installation and cannot migrate, accepting that it receives minimal maintenance and no active development.

The project's own documentation set for the new version covers preparation, installation, Raspberry Pi OS, a personal package archive, netboot clients, man pages (ltsp, ltsp.conf, ltsp-dnsmasq, ltsp-image, ltsp-info, ltsp-initrd, ltsp-ipxe, ltsp-kernel, ltsp-nfs, ltsp-remoteapps), guides, and specifications — a sign of where current effort goes. If you are ready to move, the installation page is the next step.