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=== New location === | === New location === | ||
<pre>/usr/lib/sysimage/rpm</pre> | <pre>/usr/lib/sysimage/rpm</pre> | ||
<code>/var/lib/rpm</code> will be a symlink pointing to <code>/usr/lib/sysimage/rpm</code> | <code>/var/lib/rpm</code> will be a symlink pointing to <code>/usr/lib/sysimage/rpm</code> | ||
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== Upgrade/compatibility impact == | == Upgrade/compatibility impact == | ||
<!-- What happens to systems that have had a previous versions of Fedora installed and are updated to the version containing this change? Will anything require manual configuration or data migration? Will any existing functionality be no longer supported? --> | <!-- What happens to systems that have had a previous versions of Fedora installed and are updated to the version containing this change? Will anything require manual configuration or data migration? Will any existing functionality be no longer supported? --> | ||
Change will | Change will be applied to offline upgrades, similar to the RPM sqlite database change. A systemd service will move the rpmdb from /var to /usr, then create a symlink pointing to /usr from /var. | ||
1. Create `/usr/lib/sysimage/rpm` | |||
2. Create symlinks in `/usr/lib/sysimage/rpm/` pointing to files in `/var/lib/rpm/` | |||
3. Change the dbpath in `/usr/lib/rpm/macros` to `/usr/lib/sysimage/rpm` | |||
4. Request rpm rebuild the database | |||
5. Remove `/var/lib/rpm` and create a symlink `/var/lib/rpm` -> `/usr/lib/sysimage/rpm` | |||
<!-- REQUIRED FOR SYSTEM WIDE CHANGES --> | <!-- REQUIRED FOR SYSTEM WIDE CHANGES --> | ||
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== How To Test == | == How To Test == | ||
<!-- REQUIRED FOR SYSTEM WIDE CHANGES --> | |||
* Since this will apply to new clean installs only, we'll be testing that the change appears only in Rawhide and does not appear on upgrades. | * Since this will apply to new clean installs only, we'll be testing that the change appears only in Rawhide and does not appear on upgrades. | ||
== User Experience == | == User Experience == | ||
Revision as of 17:44, 28 December 2021
Relocate RPM database to /usr
Summary
Currently, the RPM databases is located in /var. Let's move it to /usr. The move is already under way in rpm-ostree-based installations, and in (open)SUSE.
Owner
- Name: Chris Murphy
- Email: chrismurphy@fedoraproject.org
- Name: Michel Alexandre Salim
- Email: salimma@fedoraproject.org
Current status
- Targeted release: Fedora Linux 36
- Last updated: 2021-12-28
- FESCo issue: <will be assigned by the Wrangler>
- Tracker bug: <will be assigned by the Wrangler>
- Release notes tracker: <will be assigned by the Wrangler>
Detailed Description
Current location
/var/lib/rpm
New location
/usr/lib/sysimage/rpm
/var/lib/rpm will be a symlink pointing to /usr/lib/sysimage/rpm
Changing the file system layout to accommodate a snapshot+rollback regime is implied, but not required by this proposal. For example, Fedora has long placed /home on a separate subvolume (or file system) so it can be isolated from system root. Likewise, it makes sense to isolate /var/log and possibly /var/lib/libvirt/images so these locations continue to carry forward in time, even if the system root does a rollback.
Feedback
There will be no change to DNF as part of this change proposal. DNF's history will remain in /var until DNF 5. Discussion continues about the effect of a snapshot+rollback regime on DNF history. Relocate DNF history to /usr.
Upstream RPM accept the change, but institutionally don't like the loss or weakening of a very well known location for the database, and anticipate complaints.
Benefit to Fedora
- The RPM database primarily describes the state of
/usr. Storing the databases in/usrwill more easily facilitate OS rollback, without affecting/var.
- Helps align Fedora variants with each other
- rpm-ostree based systems (including CoreOS, IoT, Silverblue, Kinoite) already use
/usr/lib/sysimagefor rpmdb.
- rpm-ostree based systems (including CoreOS, IoT, Silverblue, Kinoite) already use
- Consistency with another RPM-based distro, (open)SUSE has made this change
- Accounts for various snapshot+rollback regimes, i.e. it's a beneficial change whether Btrfs or device-mapper based regimes.
Scope
- Proposal owners:
- changes in rpm package
- create the new path
- create a symlink for the old path pointing to new path
- changes in rpm package
- Other developers:
- changes in SElinux policy
- Release engineering: #Releng issue 10441
- Policies and guidelines: N/A (not needed for this Change)
- Trademark approval: N/A (not needed for this Change)
- Alignment with Objectives:
Upgrade/compatibility impact
Change will be applied to offline upgrades, similar to the RPM sqlite database change. A systemd service will move the rpmdb from /var to /usr, then create a symlink pointing to /usr from /var.
1. Create /usr/lib/sysimage/rpm
2. Create symlinks in /usr/lib/sysimage/rpm/ pointing to files in /var/lib/rpm/
3. Change the dbpath in /usr/lib/rpm/macros to /usr/lib/sysimage/rpm
4. Request rpm rebuild the database
5. Remove /var/lib/rpm and create a symlink /var/lib/rpm -> /usr/lib/sysimage/rpm
How To Test
- Since this will apply to new clean installs only, we'll be testing that the change appears only in Rawhide and does not appear on upgrades.
User Experience
Users will notice:
- symlink in the old locations for the databases, pointing to the new location
Otherwise, the change should be invisible to users.
Dependencies
rpm-ostreeprobably should make/usr/share/rpma symlink to/usr/lib/sysimage/rpm, rather than the reverse as it is currently.PackageKitmight use inotify on/var/lib/rpmneed to check if it does and whether it should be changed or add the additional path
Contingency Plan
- Contingency mechanism: Revert the change, try again the next Fedora release.
- Contingency deadline: Beta freeze
- Blocks release? Yes