'''1999''':

*Nov 1999: SWsoft chief scientist formulated three main components of Linux containers: a set of processes with namespace isolation, a file system to share code and RAM, and an isolation in resources.

'''2000''':

*Feb 2000: 5 people started working on the first mockup version of Virtuozzo (namespaces, isolation, vzfs).*Jul 2000: limited public beta testing was started on two public servers (Virtuozzo 0.1 and control panels). The number of VEs reached 5000 during summer.

'''2002''':

*Jan 2002: SWsoft (now known as Odin) initially released a product for Linux named Virtuozzo.

'''2005''':

*2005: SWsoft created the OpenVZ Project to release the core of Virtuozzo under GNU GPL.*2005: SWsoft acquired a hosting/development company "Express" with their own containers for FreeBSD (they were later dropped due to small number of clients).

'''2006''':

*Jan 2006: Rebase to kernel 2.6.15.*Oct 2006: Port to SPARC and PPC.*Nov 2006: Port to 2.6.18 kernel.*Nov 2006: OpenVZ added live migration capability.

'''2007''':

*Mar 2007: Port to RHEL5 kernel.*Mar 2007: Port to 2.6.20 kernel.

'''2008''':

*Apr 2008: Rebase to kernel 2.6.25.*Oct 2008: Port to ARM.

'''2009''':

*Aug 2009: Parallels company is in Top 10 Linux kernel contributors with their patches for Linux containers. The contributions to the kernel at that time were PID, IPC, and network namespaces, the last one being the biggest.

'''2011''':

*Jul 2011: Pavel Emelyanov sent initial RFC and code. The idea of CRIU, of course, came up earlier when OpenVZ team realised that merging in-kernel checkpoint/restore was impossible. Re-implementing it in userspace looked crazy for everyone, and Andrew Morton's and Linus Torvalds' initial reaction was similar ("some crazy russians").*Sep 2011: Cyrill Gorcunov made first commit to CRIU project.

'''2012''':

*Jul 2012: CRIU v0.1 became available.*Oct 2012: vzctl for upstream Linux kernel became available.

'''2014''':

*Dec 2014: Parallels announced merging OpenVZ and Parallels Cloud Server into single common open source codebase.

'''2015''':

*Apr 2015: Source code of RHEL7-based kernel was published and kernel development process became open.*Jun 2015: Source code of most userspace utilities was published.*Jul 2015: yum repository with Virtuozzo RPM packages and installation ISO image was published and regularly updated.*Jul 2015: Virtuozzo 7 Technical Preview - Containers was announced.