Exercise: Serve your own repository

Build a small repository from downloaded packages, define it for dnf with signature checking left on, and install software from it alone.

Serve your own repository

Download packages with their dependencies.
Create repository metadata with createrepo_c.
Define a repository, keep gpgcheck on, and install from it only.

Start the exercise

On workstation, start the exercise. It installs dnf-plugins-core and createrepo_c on servera, and removes a repository left by an earlier run.

[student@workstation ~]$ lab start sa-local-repo

Later tasks assume that you are logged in to the server they name: ssh student@servera from workstation, then sudo -i for a root shell.

Look at the existing repositories

On servera as root (sudo -i), list the enabled repositories and find the gpgkey line that the distribution's repositories use.

[student@workstation ~]$ ssh student@servera
[student@servera ~]$ sudo -i
[root@servera ~]# dnf repolist
repo id                         repo name
appstream                       Rocky Linux 9 - AppStream
baseos                          Rocky Linux 9 - BaseOS
extras                          Rocky Linux 9 - Extras
[root@servera ~]# grep -h '^gpgkey' /etc/yum.repos.d/*.repo | sort -u
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-Rocky-9

On Red Hat Enterprise Linux the key path is different (RPM-GPG-KEY-redhat-release). Always copy what your own system shows.

Download the packages

Create /srv/localrepo and download zip with its dependencies into it. Check one signature with rpm -K.

[root@servera ~]# mkdir -p /srv/localrepo
[root@servera ~]# dnf download --resolve --destdir /srv/localrepo zip
(1/2): zip-3.0-35.el9.x86_64.rpm                1.2 MB/s | 263 kB     00:00
(2/2): unzip-6.0-60.el9_8.x86_64.rpm            778 kB/s | 180 kB     00:00
[root@servera ~]# ls -l /srv/localrepo
-rw-r--r--. 1 root root 184214 Oct  3 17:26 unzip-6.0-60.el9_8.x86_64.rpm
-rw-r--r--. 1 root root 269065 Oct  3 17:26 zip-3.0-35.el9.x86_64.rpm
[root@servera ~]# rpm -K /srv/localrepo/zip-3.0-35.el9.x86_64.rpm
/srv/localrepo/zip-3.0-35.el9.x86_64.rpm: digests signatures OK

Create the metadata and define the repository

Build the metadata, then create /etc/yum.repos.d/local.repo for a repository localrepo at file:///srv/localrepo, enabled, with gpgcheck=1 and the key you found. Clean dnf's cache and make sure the repository is listed.

[root@servera ~]# createrepo_c /srv/localrepo
Directory walk started
Directory walk done - 2 packages
...output omitted...
[root@servera ~]# ls /srv/localrepo/repodata | head -3
044c77de9e91d22279d49d9488bfb4e5bb43dabc0cb3fc16ac6f11d09150ce58-other.sqlite.bz2
...output omitted...
[root@servera ~]# cat > /etc/yum.repos.d/local.repo <<'EOT'
[localrepo]
name=Local repository
baseurl=file:///srv/localrepo
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-Rocky-9
EOT
[root@servera ~]# dnf clean all > /dev/null
[root@servera ~]# dnf repolist
repo id                         repo name
appstream                       Rocky Linux 9 - AppStream
baseos                          Rocky Linux 9 - BaseOS
extras                          Rocky Linux 9 - Extras
localrepo                       Local repository

Install from it, and only from it

List the packages available from localrepo alone, install zip using only that repository, and confirm where it came from.

[root@servera ~]# dnf --disablerepo='*' --enablerepo=localrepo list available
Available Packages
unzip.x86_64                       6.0-60.el9_8                        localrepo
zip.x86_64                         3.0-35.el9                          localrepo
[root@servera ~]# dnf --disablerepo='*' --enablerepo=localrepo install -y zip
...output omitted...
Installed:
  unzip-6.0-60.el9_8.x86_64                zip-3.0-35.el9.x86_64

Complete!
[root@servera ~]# dnf info zip | grep 'From repo'
From repo    : localrepo

Grade and finish

Check your work with lab grade sa-local-repo, then put the exercise away with lab finish sa-local-repo.