How to Set Up a Local Yum/DNF Repository on CentOS 8

In this article, you will learn how you can locally set up a DNF or YUM repository on your CentOS 8 system using an ISO or an installation DVD.

CentOS 8 ships with 2 repositories: BaseOS and AppStream (Application Stream) – So what’s the difference between the two repositories?

The BaseOS repository consists of the requisite packages required for the existence of a minimal operating system. On the other hand, AppStream comprises the remaining software packages, dependencies, and databases.

Related Read: How to Create Local HTTP Yum/DNF Repository on RHEL 8

Now let’s roll up our sleeves and set up a local YUM/DNF repository in CentOS 8.

Step 1: Mount CentOS 8 DVD Installation ISO File

Begin by mounting the ISO file to a directory of your choice. Here, we have mounted in on /opt directory.

# mount CentOS-8-x86_64-1905-dvd1.iso /opt
# cd /opt
# ls

Step 2: Create a CentOS 8 Local Yum Repository

In the mounted directory where your ISO is mounted, copy the media.repo file to the /etc/yum.repos.d/ directory as shown.

# cp -v /opt/media.repo  /etc/yum.repos.d/centos8.repo

Next, assign file permissions as shown to prevent modification or alteration by other users.

# chmod 644 /etc/yum.repos.d/centos8.repo
# ls -l /etc/yum.repos.d/centos8.repo

We need to configure the default repository file residing on the system. To check the configurations, use the cat command as shown.

# cat etc/yum.repos.d/centos8.repo

We need to modify the configuration lines using a text editor of your choice.

# vim etc/yum.repos.d/centos8.repo

Delete all the configuration, and copy & paste the configuration below.

[InstallMedia-BaseOS]
name=CentOS Linux 8 - BaseOS
metadata_expire=-1
gpgcheck=1
enabled=1
baseurl=file:///opt/BaseOS/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial

[InstallMedia-AppStream]
name=CentOS Linux 8 - AppStream
metadata_expire=-1
gpgcheck=1
enabled=1
baseurl=file:///opt/AppStream/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial

Save the repo file and exit the editor.

After modifying the repository file with new entries, proceed and clear the DNF / YUM cache as shown.

# dnf clean all
OR
# yum clean all

To confirm that the system will get packages from the locally defined repositories, run the command:

# dnf repolist
OR
# yum repolist

Now set ‘enabled’ parameter from 1 to 0 in CentOS-AppStream.repo and CentOS-Base.repo files.

Step 3: Install Packages Using Local DNF or Yum Repository

Now, let’s give it a try and install any package. In this example, we are going to install NodeJS on the system.

# dnf install nodejs
OR
# yum install nodejs

And this is a clear indicator that we have successfully set up a local DNF/YUM repository on CentOS 8.