Introduction

The Linux Containers project maintains Long Term Support (LTS) releases for its core projects. Those come with 5 years of support from upstream with the first two years including bugfixes, minor improvements and security fixes and the remaining 3 years getting only security fixes.

This is now the sixth round of bugfix releases for LXC, LXCFS and Incus 6.0 LTS.

LXC

LXC is the oldest Linux Containers project and the basis for almost every other one of our projects. This low-level container runtime and library was first released in August 2008, led to the creation of projects like Docker and today is still actively used directly or indirectly on millions of systems.

Announcement: https://discuss.linuxcontainers.org/t/lxc-6-0-6-lts-has-been-released/26294

Highlights of this point release:

• Support for alternative compression formats in lxc-local
• Updated AppArmor profile generation (allows running newer runc)
• Support for --rbduser with the ceph backend
• Improved systemd scope handling for unprivileged containers
• Added support for OpenRC as an init system
• Fixed a data transfer race in the attach logic when using io_uring
• Fixed handling of lxc.cap.keep and lxc.cap.drop in configuration

LXCFS

LXCFS is a FUSE filesystem used to workaround some shortcomings of the Linux kernel when it comes to reporting available system resources to processes running in containers. The project started in late 2014 and is still actively used by Incus today as well as by some Docker and Kubernetes users.

Announcement: https://discuss.linuxcontainers.org/t/lxcfs-6-0-6-lts-has-been-released/26263

Highlights of this point release:

• Fix issue with CPU count in /proc/stat
• Fix issue causing the cgroup2 mount flags to be changed on startup

Incus

Incus is our most actively developed project. This virtualization platform is just over a year old but has already seen over 3500 commits by over 120 individual contributors. Its first LTS release made it usable in production environments and significantly boosted its user base.

Announcement: https://discuss.linuxcontainers.org/t/incus-6-0-6-lts-has-been-released/26380

Highlights of this point release:

• USB CD-ROM handling for VMs
• Configurable console behavior in the CLI
• tmpfs and tmpfs-overlay disks for containers
• IncusOS management commands
• Control over out-of-memory priority
• Override-able configuration and devices on backup import
• database-client cluster role
• Support for parent=none on OVN uplink networks
• Cluster groups in configuration preseed
• Systemd credentials
• Storage volume file operations
• Export of ISO volumes
• BPF token delegation
• MacOS support for the Incus agent
• VirtIO sound card in VMs
• Support for detaching USB devices without removing them
• dns.mode for OVN network
• Configurable MAC address patterns
• Extended IncusOS CLI
• Initial SELinux support
• Improved Windows agent support
• Serial devices in the resources API
• Bandwidth limits on OVN NICs
• Support for multi-object deletion in most CLI commands
• Ability to turn off passthrough of PCI firmware to VM
• PKCS12 generation in the CLI
• Option for raw units in CLI CSV output
• QCOW2 formatted volumes on clustered LVM
• Standalone incus cluster join command
• Configuration file for the VM agent
• Reverse DNS records in OVN
• incus wait command
• Automatic SR-IOV selection for network interfaces
• attached and connected properties on network interfaces
• Parallel instance startup
• Network restrictions through OIDC claims
• Better support for the SOA in network zones
• Support for forceful (recursive) file deletion in API
• vsock support for the WIndows agent
• Direct backup retrieval
• Disk-only snapshot restoration
• Dedicated storage volume for server logs
• QCOW2 storage improvements
• lvmcluster storage pool resizing
• Automatic snapshot removal on restore with lvmcluster
• Full USB controller passthrough in unix-hotplug
• Certificate information in the authorization scriptlet
• VM fast reboot
• Image server URL restrictions in projects
• URL based imports in incus-migrate
• Multi-domain certificates with ACME
• Control of trusted property on SR-IOV NICs
• Additional cluster member states to track evacuation
• Cluster restore without instance migration
• Instance boot time metrics

What’s next?

We’re expecting one last round of LTS bugfix release for the 6.0 branches around May/June 2026 following the release of the 7.0 LTS in April 2026. After that, the 6.0 branches will be in security-only maintenance mode for the remaining three year of support while we focus our bugfix and improvements efforts on the 7.0 branches.