Key Differences Between SUSE Linux Enterprise 15 and 16

SLE 15 uses Service Packs (SPs) for annual updates, such as SP1, SP2, SP3, SP4, SP5, SP6, and SP7, which is the last SP released for SLE 15.

SLE 16 introduces a new naming schema for versions, using minor releases like 16.0, 16.1, instead of service packs. Minor releases are scheduled annually and always in November. The initial release, 16.0, is planned for November 2025.

Each SUSE Linux Enterprise Server 15 service pack has general support for 18 months, giving you six months overlap with the next service pack. SUSE offers various extended support options like Long Term Service Pack Support (LTSS, 3 years) and Extended Service Pack Overlap Support (ESPOS). The total support for SLE 15 covers up to 13 years: 10 years general support plus 3 years LTSS. SUSE Linux Enterprise Server for SAP applications 15 SPs has a total support period of 4.5 years.

SLES 16 is ready for the future beyond 2038. Each SLES 16 minor release has 24 months of general support, giving you 12 months overlap with the next minor release. This means SUSE Linux Enterprise Server doubles the time to upgrade at no extra cost. The last minor release 16.6 will have 48 months of general support to complete a 10 year lifecycle. General support is expected to end in in November 2035. Additional Long Term Support (LTS) is available for 3 years for all service packs, with LTS and Extreme LTS beyond 2040. SUSE Linux Enterprise Server for SAP applications 16 has general support for 2 years plus 3 years extended support.

In SLE 15 and earlier, YaST was used for installation, configuration and systems management. Unattended and scripted installation was performed by AutoYaST.

In SLE 16, systems management sees significant changes:

These changes in SLE 16 aim to provide better integration with Salt and Ansible, allow remote installation via a Web browser, and offer different interfaces (Web, CLI, HTTP API) for controlling the process.

SLE 15 uses AppArmor by default. SELinux is shipped without policies.

SLE 16 ships SELinux with policies for over 400 modules by default, confining almost the whole system. Parts of the system can run unconfined if desired. SUSE Linux Enterprise Server for SAP applications 16 has improved workload isolation with SELinux, providing isolation for data and data flows, and for containers.

SLE 15 used wicked and NetworkManager.

SLE 16 focuses on a single stack using NetworkManager.

SLE 15 offered ready-to-run images for virtual machines or public clouds and installation media for manual deployment with YaST or automated with AutoYaST. It used a special installation environment with linuxrc-driven configuration. AutoYaST profile import was a one-off task only.

SLE 16 uses ready-to-run images for virtual machines or public clouds, and manual/automated deployment with Agama. The Agama installer is accessible via a Web interface, command line or HTTP API. Agama allows repeated configuration import. It uses a standard live medium with dracut, systemd, and NetworkManager and provides a backward-compatibility layer with selected linuxrc options.

SLE 15 used systemd with native units and compatibility for 3rd party SysV init scripts.

SLE 16 completes the transition from SysV init and uses systemd native units exclusively.

In SLE 15, the default OS configuration was primarily in /etc.

In SLE 16, defaults are in /usr and /etc is for customization. This separation of vendor-provided defaults and administrator customization allows easier updates and — optionally — read-only /usr file system.

In SLE 15 /tmp was a regular folder or partition. In the default configuration with Btrfs as root file system, it was a Btrfs subvolume.

In SLE 16, /tmp uses the tmpfs file system, which stores data in physical RAM and/or swap space, making it very fast for read and write operations.

Important: /tmpis no longer persistent

On tmpfs, the content of /tmp is not persistent between reboots. If you have applications that write persistent data to /tmp, adopt them to use a different location such as /var/cache.

Important: Do not oversize /tmp

Oversizing tmpfs file system instances beyond the the sum of physical RAM and swap space of a system can lead to deadlock situations where the system becomes unresponsive due to insufficient available memory.

SLE 15 used GNOME as the default desktop environment. SUSE Linux Enterprise Desktop and SUSE Linux Enterprise Workstation Extension shared desktop productivity tools.

SLE 16 uses a minimal GNOME desktop. This helps minimize the security surface. SUSE Linux Enterprise Desktop is not planned for 16.0.

System: 32-bit application support is removed. The Linux kernel can still enable 32-bit system calls by installing the grub2-compat-ia32 package from the SUSE Package Hub.

System: SysV init scripts are removed; use native systemd units instead.

Network: wicked is removed in favor of NetworkManager.

Network: NIS is no longer used; choose LDAP instead.

Network: The ISC DHCP server was removed in favor of the more modern Kea DHCP.

Virtualization: Xen was removed in favor of KVM. You can no longer run SLE 16 as Xen host or as paravirtualized guest (PV). Running SLE 16 as fully virtualized Xen guest (HVM) or using hardware virtualization features (PVH) is still possible.

Windows Subsystem for Linux: Support for WSL1 was removed in favor of WSL2, offering a full Linux kernel with complete system call compatibility.