Conflicting repositories: --enablerepo, includepkgs and cost (Rocky 9, tested)

When to use it

dnf installs a package from a repo you did not expect, or two repos both offer the same name and you want to pin the source. On Rocky 9 there are three groups of tools: temporarily toggling repos, filtering inside a repo definition, and cost weighting. The third one did not behave as documented in this test — the page says so below.

Option one: toggle repos for one command

sudo dnf --disablerepo="*" --enablerepo=multi list available

Available Packages
libpsl.aarch64                    0.21.1-5.el9     multi
publicsuffix-list-dafsa.noarch    20210518-3.el9   multi
tree.aarch64                      1.8.0-10.el9     multi
wget.aarch64                      1.21.1-11.el9_8  multi

--disablerepo="*" turns everything off first, then --enablerepo= enables the one you trust — the most predictable approach, and it only applies to that command, so a risky repo is never left permanently enabled.

Option two: filter packages in the repo definition

[multi]
name=Multi
baseurl=file:///srv/multi
enabled=1
gpgcheck=0
includepkgs=tree

Available Packages
tree.aarch64    1.8.0-10.el9    multi

includepkgs=tree makes the repo expose only tree; every other package (including wget and its dependencies) becomes invisible.

The inverse uses excludepkgs:

excludepkgs=wget

Available Packages
libpsl.aarch64                    0.21.1-5.el9     multi
publicsuffix-list-dafsa.noarch    20210518-3.el9   multi
tree.aarch64                      1.8.0-10.el9     multi

wget disappears from the list; the other three remain.

Option three: cost — it did not work in this test

Two local repos provide the same rpm, with cost=10 and cost=20; repoquery --location shows which one dnf would use:

sudo dnf --disablerepo="*" --enablerepo=A,B repoquery --location tree

file:///srv/repoB/tree-1.8.0-10.el9.aarch64.rpm

Swapping the costs (A=99, B=1) and running again still resolved to repoB. In other words, cost did not change the selection in this scenario.

Conclusion: do not treat cost as a reliable cross-repo priority mechanism. When you must pin a source, name it with --enablerepo or exclude the unwanted source with excludepkgs.

Common traps

• Permanently enabling a third-party repo (enabled=1): a later dnf update may replace system packages with third-party builds; prefer --enablerepo for one command;
• includepkgs takes package names, not file names: write tree, not tree-1.8.0-10.el9.aarch64;
• Editing a repo file without dnf clean all: the metadata cache still applies and list available appears unchanged.

Practice: install only from the repo you choose

Prerequisite: Rocky 9 with a local repo built as in Offline package installs.

sudo dnf --disablerepo="*" --enablerepo=multi install -y tree

Checks:

1. dnf --disablerepo="*" --enablerepo=multi list available | grep -c tree → 1
2. Add includepkgs=tree to /etc/yum.repos.d/multi.repo, run dnf clean all, repeat step 1 → wget no longer appears
3. Replace with excludepkgs=wget (remove includepkgs) → wget is absent from the list

Next steps

• Building a local repo: Offline package installs
• Repos and defaults: Rocky repositories
• Rolling back a bad install: dnf history undo