How to do yum backup and restore?

Is there a way to开发者_JS百科 make a backup of package that will be change while yum update? For example when I do yum update lighttpd is there a way to backup and restore lighttpd if yum update will be unsuccessful or it will result in unsuspected errors or bugs?

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If you're using RPM before 4.6.0 (it's removed in newer versions), you can use rpm --rollback mechanism like in this old tutorial or in a more complete article with some functionality explanation. The --rollback feature is an automatic solution that was removed since it isn't reliable.

You can have a manual solution, keeping a list of all the packages before the yum update and reinstall needed old rpms possibly using --oldpackage like rpm -Uvh --oldpackage foo-1-1.i386.rpm:

To get a list of all installed packages, sorted by installation time:

rpm -q -a --queryformat '%{INSTALLTIME} %{NAME}-%{VERSION}-%{RELEASE}\n' | sort -n 

(Source)

If you're using Fedora, here is an official guide to upgrade the system using the installer with an example of how to create a list of system current installed packages and how to restore most of old software after an upgrade.

If you want a generic approach to get a list of installed software (not only rpm based), you can follow this article as well.

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If you are using a repo. that keeps all old versions around, you can just do "yum downgrade lighttpd" (and with newer yum's "yum history undo"). If you aren't, then you can keep a local copy of the old rpm and use "yum downgrade lighttpd*.rpm" (although that is trickier). It's possible that some problems won't be fixed by this, but those should be very rare and downgrade is unlikely to change anything else as a side effect.

Very recently a plugin "yum-plugin-fs-snapshot" has been created, which will automatically take an FS snapshot (btrfs, or LVM) before doing an upgrade ... thus. you can then just rollback to the snapshot. This is a big change though, so I don't recommend it.

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I use etckeeper to track changes of files under /etc. etckeeper puts /etc under version control (it supports multiple version control systems, including Git, Mercurial and Bazaar) and integrates with the package management systems of a number of Linux distros (APT, YUM, Pacman).

If something bad happens during an upgrade or so, I can rollback anything.