LXC

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For the Imperial Japanese Navy Air Service designation for a single Curtiss-Wright CA-1 amphibian aircraft, acquired for evaluation, see Curtiss-Wright LXC.
Linux Containers
Developer(s) Daniel Lezcano, Serge Hallyn, Stéphane Graber
Initial release August 6, 2008; 6 years ago (2008-08-06)[1]
Stable release 1.0.5[2] / 14 July 2014; 5 months ago (2014-07-14)
Development status Active
Written in C, python3, shell, lua
Operating system Linux
Platform x86, x86-64, IA-64, PowerPC, SPARC, Itanium, ARM
Type OS-level virtualization
License GNU LGPL v.2.1 (some components under GNU GPL v2 and BSD)
Website linuxcontainers.org

LXC (Linux Containers) is an operating system–level virtualization method for running multiple isolated Linux systems (containers) on a single control host.

The Linux kernel comprises cgroups for resource isolation (CPU, memory, block I/O, network, etc.) that does not require starting any virtual machines. Cgroups also provides namespace isolation to completely isolate applications' view of the operating environment, including process trees, network, user ids and mounted file systems.

LXC combines cgroups and namespace support to provide an isolated environment for applications. Docker can also use LXC as one of its execution drivers, enabling image management and providing deployment services.

Overview[edit]

LXC provides operating system-level virtualization through a virtual environment that has its own process and network space, instead of creating a full-fledged virtual machine. LXC relies on the Linux kernel cgroups functionality that was released in version 2.6.24. It also relies on other kinds of namespace-isolation functionality, which were developed and integrated into the mainline Linux kernel.

Security[edit]

Originally, LXC containers were not as secure as other OS-level virtualization methods such as OpenVZ: in Linux kernels before 3.8, the root user of the guest system could run arbitrary code on the host system with root privileges, much like chroot jails.[3] Starting with the 1.0 release, containers run as regular users on the host using "unprivileged containers".[4] Unprivileged containers are more limited in that they cannot access hardware directly. Nevertheless, even privileged containers should provide adequate isolation in the 1.0 security model, if properly configured.[4]

Alternatives[edit]

LXC is similar to other OS-level virtualization technologies on Linux such as OpenVZ and Linux-VServer, as well as those on other operating systems such as FreeBSD jails, AIX Workload Partitions and Solaris Containers. In contrast to OpenVZ, LXC works in the vanilla Linux kernel requiring no additional patches to be applied to the kernel sources. Version 1 of LXC, which was released on 20 February 2014, is a long-term supported version and intended to be supported for five years.[5]

See also[edit]

References[edit]

  1. ^ "LXC - Linux Containers". linuxcontainers.org. Retrieved 2014-11-10. 
  2. ^ Download lxc
  3. ^ Marco, d'Itri (2011). "Evading from linux containers". Archived from the original on 9 January 2014. Retrieved 12 February 2014. 
  4. ^ a b Graber, Stéphane (1 January 2014). "LXC 1.0: Security features [6/10]". Retrieved 12 February 2014. However, at least in Ubuntu, our default containers ship with what we think is a pretty good configuration of both the cgroup access and an extensive apparmor profile which prevents all attacks that we are aware of. [...] LXC is no longer running as root so even if an attacker manages to escape the container, he’d find himself having the privileges of a regular user on the host 
  5. ^ Stéphane Graber (2013-12-20). "LXC 1.0: Your first Ubuntu container". Stgraber.org. Retrieved 2014-02-23. 

External links[edit]