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== Dependencies ==
== Dependencies ==
None.
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 ==
== Contingency Plan ==

Revision as of 00:15, 14 July 2009

Rebootless Installer

Summary

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.

Owner

  • email: dmc.fedora AT filteredperception DOT org

Current status

  • Targeted release: 12
  • Last updated: 2009-07-13
  • Percentage of completion: 51%

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.

Benefit to Fedora

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

Scope

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.

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 preciousness 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 (I'm not even convinced yet that it can partition, it was a guess). So if you need to adjust or create any partitions, you should do so with your favorite tool (fdisk) before running the installer.

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.

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, ...

Dependencies

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.

Documentation

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 will now be the installed OS.

Comments and Discussion