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Rebootless Installer


The ZyX-LiveInstaller if also installed can be used instead of Anaconda from the LiveOS to install to system disk. The difference is that no reboot is required after installation completes.


  • email: dmc.fedora AT filteredperception DOT org

Current status

  • Targeted release: 12
  • Last updated: 2009-07-17
  • Percentage of completion: 53%

Detailed Description

The ZyX Graphical Rebootless LiveOS Installer will allow you to install a 'live operating system'(LiveOS) to a system storage volume, just like the standard Fedora LiveOS installer (anaconda). However, unlike traditional *nix installers, you will not need to reboot after installation.

This is accomplished by copying the running 'live' root filesystem block for block, while in use, to the destination volume. This is done using a devicemapper 'mirror' device. Once the mirroring completes, the resources for the original LiveOS root filesystem are released, leaving a normally[1] installed system. Thus you could for instance, eject the LiveCD (or remove LiveUSB), then insert a blank media, and immediately burn a replicated copy of the LiveOS to give to someone, while someone else is already using the freed LiveOS media to install another system. All before shutting down or rebooting the system for the first time.

[1] The only minor difference between the final installed system, and a traditionally installed system, is that until the first reboot, the mounted root filesystem will be accessed through a nearly no-op simple devicemapper linear layer. In other words, until the next boot, a performance hit no worse than any other rootfs-on-lvm installation.

clarification note: This is only an alternate method to the current LiveOS installer. This method does not provide any interesting alternative to the old school non-live DVD installer. Though it does provide an alternative for DVD-sized LiveOS spin's installers. This architecture could provide a rebootless equivalent to what it sounds like opensuse achieves with kexec, but that is just an idea with no proof of concept yet, unrelated to this feature. Nor does this feature pertain in any way to upgrade scenarios, just as the current Fedora LiveOS installer does not (I believe) support any kind of upgrade. (I believe vanilla anaconda may be usable to perform upgrades from the current LiveCD, but that is not a use-case that is well documented/advertised. Wiki editors, please confirm/deny)

Benefit to Fedora

Some users and reviewers of Fedora might like the lack of required reboot as part of installation.


The currently published srpm at http://viros.org/rebootless would need to be added to the fedora/rawhide repo, and then included in whichever spins accept the feature. Testing of the installer would be required, as well as fixing bugs and enhancing as much as time permits.

The size of the installer i386 rpm, which one would guess to be roughly the same footprint on the 700MB livecd, is about 100KB. So even knowing the scarcity of space on the livecd, this feature can be justified at least in terms of footprint.

How To Test

All you should need to test out, is a system whose disk data you don't care about, a stock f11 i686 livecd or liveusb, and an internet connection. Boot up, fire up firefox, go to http://viros.org/rebootless, install by clicking the rpm link, and run the new desktop icon/launcher. If all goes well, you should be able to eject the livecd or remove the liveusb without powering down, and use the system normally from then on.

Partition creation/management is currently outsourced to palimpsest. There are no choices with the bootloader, it gets installed to the MBR of /boot partition's disk, with a single configuration. Anything normally done during firstboot, you will need to do as normal system reconfiguration, i.e. system-config-time, adduser, changing rootpw, etc...

If you notice any discrepancy between the resulting system and what you would expect from a normal LiveOS installation, and it is not already listed on the project's webpage and/or ROADMAP file, please submit feedback to the author at bugz AT viros DOT org.

Specifically, different configurations of real and virtual systems should be tested. The author for instance does not have easy access to any x64 hardware at the moment. PPC will definitely not work right now either.

note: for the timebeing, packages are not signed, but sha512sums are available in the download directory.

User Experience

See the screenshot tour

The key difference with the ZyX-LiveInstaller is that after installation, the running LiveOS *is* the installed system. Presently there are some minor things listed in the upstream ROADMAP that need to be cleaned up to give the user the closest possible experience to that of the normal Anaconda installer. I.e. no firstboot, no user creation wizard, no root password change wizard, ...

If you want to listen to my commentary on a video of installation to an acer aspire one netbook, you can check out 18 minutes of video (split in 2 for youtube length requirements). In the video I demonstrate installing the package from wifi, as well as pre-first-reboot hibernation and full reboot. part 1 and part 2.


This implementation of rebootless installation is dependent on the current devicemapper overlay architecture used for Fedora LiveCD/USBs. This is not a problem for F12, however should F13,etc... choose to migrate to a unionfs architecture (as ubuntu did ages ago), this feature would have to be removed. This is in fact a strong selling point for accepting the feature now, as opposed to deferring to a possible subsequent release. Having this feature, even in an early experimental form in F12, would provide the ideal feedback for determining whether it might be a reason to hold off on such a unionfs adoption.

Contingency Plan

None necessary, revert to previous release behaviour.


All documentation can presently be found at the project page ZyX-LiveInstaller Project

Pay particular attention to the source tree (browsable online), under ./info/, i.e. ROADMAP and HACKING

Release Notes

  • An experimental new rebootless installer has been included with the LiveCD/USB. To access it launch 'ZyX-LiveInstaller' from the 'System Tools' menu instead of clicking on the 'Install to Hard Drive' desktop icon. This installer is still experimental, and lacking features of the normal installer, however, at the end of the installation, the LiveOS you have been using since boot will now be the installed OS. Only use this if you are comfortable with experimental code being in charge of the creation of your root filesystem and bootloader installation.

Comments and Discussion