Learn how to – How To Create and Use Local CentOS 7 YUM Repository

Learn how to – How To Create and Use Local CentOS 7 YUM Repository.

As a Linux System Administrator, it is almost an obligation to install Software Packages on a server or fleet of servers. However, it’s not always ideal to install packages from official CentOS repositories over the internet. A good example is when you have slow internet connection and would like to save bandwidth by creating a repository on LAN. Or on Environments with strict security policies requiring all patching of systems to be done within the LAN network.

This guide will help you setup a local CentOS 7 YUM repository locally in your Server / Desktop machine. We have provided all steps needed to have a working local yum repository created using CentOS DVD ISO image. Below we list all the steps to be used when creating local CentOS 7 YUM repositories.

Step 1: Download CentOS-7-x86_64-Everything ISO or CentOS 7 DVD ISO image

In this guide I’ll use the CentOS-7-x86_64-Everything-2009 ISO image which can be downloaded with curl or wget command:

curl -O http://centos.mirror.liquidtelecom.com/7.9.2009/isos/x86_64/CentOS-7-x86_64-Everything-2009.iso

You can as well use CentOS 7 DVD ISO:

curl -O http://centos.mirror.liquidtelecom.com/7.9.2009/isos/x86_64/CentOS-7-x86_64-DVD-2009.iso

Step 2: Create Mount points and Mount ISO image

After downloading, we’ll have to mount it. There are two mounting Options we can use:

Mounting the ISO file to a local directory in our Linux system

Create a directory for mounting

sudo mkdir -p /mnt/centos7

Mount ISO image of CentOS Everything or CentOS 7 DVD ISO

 sudo mount -t iso9660 -o loop CentOS-7-x86_64-Everything-2009.iso /mnt/centos7

Confirm it’s mounted using du or ls command:

$ du -sch /mnt/centos7/*
512	/mnt/centos7/CentOS_BuildTag
8.4M	/mnt/centos7/EFI
512	/mnt/centos7/EULA
18K	/mnt/centos7/GPL
68M	/mnt/centos7/images
60M	/mnt/centos7/isolinux
498M	/mnt/centos7/LiveOS
9.0G	/mnt/centos7/Packages
29M	/mnt/centos7/repodata
2.0K	/mnt/centos7/RPM-GPG-KEY-CentOS-7
2.0K	/mnt/centos7/RPM-GPG-KEY-CentOS-Testing-7
3.0K	/mnt/centos7/TRANS.TBL
9.6G	total

Mounting the ISO image file to a web server directory

I’m using Apache server running on another CentOS server.

sudo yum -y install httpd
sudo systemctl enable --now httpd

If you’re doing this on any other Linux server, replace the root directory of web server with the one provided here.

Create a directory for mounting:

sudo mkdir /var/www/html/centos7/
sudo mount -t iso9660 -o loop CentOS-7-x86_64-Everything-2009.iso /var/www/html/centos7/

The output you get from last command is:

mount: /dev/loop0 is write-protected, mounting read-only

The contents of the /var/www/html/centos/ directory should be as shown:

$ ls -lh /var/www/html/centos7/
total 1.7M
-rw-r--r--  1 root root   14 Oct 29  2020 CentOS_BuildTag
drwxr-xr-x  3 root root 2.0K Oct 26  2020 EFI
-rw-rw-r-- 17 root root  227 Aug 30  2017 EULA
-rw-rw-r-- 17 root root  18K Dec  9  2015 GPL
drwxr-xr-x  3 root root 2.0K Oct 26  2020 images
drwxr-xr-x  2 root root 2.0K Oct 26  2020 isolinux
drwxr-xr-x  2 root root 2.0K Oct 26  2020 LiveOS
drwxr-xr-x  2 root root 1.6M Oct 29  2020 Packages
drwxr-xr-x  2 root root 4.0K Oct 29  2020 repodata
-rw-rw-r-- 17 root root 1.7K Dec  9  2015 RPM-GPG-KEY-CentOS-7
-rw-rw-r-- 15 root root 1.7K Dec  9  2015 RPM-GPG-KEY-CentOS-Testing-7
-r--r--r--  1 root root 2.9K Nov  2  2020 TRANS.TBL

If you had CentOS 7 DVD ISO image on CD/DVD drive. Create a mount point and mount cdrom using the following commands:

sudo  mkdir -p /mnt/cent/cdrom
sudo mount /dev/cdrom /mnt/cent/cdrom

Step 3: Create a repo and put it inside /etc/yum/repos.d/ directory

This is done on Server with CentOS minimal installation, or server that you need to install packages on while pulling the packages from local repository you just added.

For local disk mount on /mnt

If you used local directory mount option then configure like below.

Create repository file:

sudo vim /etc/yum.repos.d/centos7-local.repo

Add contents which looks like this:

[centos7-local]
name=centos7-local
baseurl=file:///mnt/centos7/
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

For repository files on http server

The IP address of the server I’m using is 192.168.1.60. Below is the repo configuration.

[centos7-local]
name=centos7-local
baseurl=http://192.168.1.60/centos7
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

Browsing to the Web Server centos directory:

For cdrom mount point /mnt/centos/cdrom/

If you used the mount point of /mnt/centos/cdrom/:

[centos7-local]
name=centos7-local
baseurl=file:///mnt/cent/cdrom/
enabled=1
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

Then do yum clean all remove cached date and update repo list

$ sudo yum clean all
Loaded plugins: fastestmirror, langpacks, priorities
Cleaning repos: base epel extras remi-safe updates
Cleaning up everything
Cleaning up list of fastest mirrors

NOTE: Enabling the repository locally added alone is not necessary enough to let us install software packages from it. This is because by default, any package being installed will use CentOS Base repository. We’ll discuss on a working solution to this shortly.

Package groups available in CentOS 7 repository are:

$ sudo yum group list
Loaded plugins: fastestmirror
There is no installed groups file.
Maybe run: yum groups mark convert (see man yum)
Loading mirror speeds from cached hostfile
* base: mirror.bitco.co.za
* epel: epel.mirrors.ovh.net
* extras: mirror.bitco.co.za
* updates: mirror.bitco.co.za
Available Environment Groups:
Minimal Install
Compute Node
Infrastructure Server
File and Print Server
MATE Desktop
Basic Web Server
Virtualization Host
Server with GUI
GNOME Desktop
KDE Plasma Workspaces
Development and Creative Workstation
Available Groups:
CIFS file server
Compatibility Libraries
Console Internet Tools
Desktop
Desktop Platform
Desktop Platform Development
Development Tools
Eclipse
Educational Software
Electronic Lab
FCoE Storage Client
Fedora Packager
General Purpose Desktop
Graphical Administration Tools
Haskell
Legacy UNIX Compatibility
Messaging Client Support
Messaging Server Support
Milkymist
MySQL Database client
MySQL Database server
NFS file server
Network Storage Server
SNMP Support
Scientific Support
Security Tools
Server Platform
Server Platform Development
Smart Card Support
Storage Availability Tools
System Administration Tools
System Management
TeX support
TurboGears application framework
Virtualization
Web-Based Enterprise Management
Xfce
iSCSI Storage Client
Done

When other CentOS repos are enabled and you specify centos-local repo, yum will always try to download latest package from repo with the latest package. The default repo being CentOS Base repo.

If you want to force yum to use local repository, you have to disable all other repos and enable them once you are done.You have two options you can use to achieve this.

Option: Move all other repositories to backup folder

The simplest solution can be like below:

mkdir ~/repos
cp -r /etc/yum.repos.d/* ~/repos/
ls -l ~/repos/
rm -rf /etc/yum.repos.d/*
ls -l /etc/yum.repos.d/

Copy local repository file back:

sudo cp ~/repos/centos7-local.repo /etc/yum.repos.d/

Check to see if successfully added:

sudo yum repolist

Example of package installation from Local repository:

To install all packages belonging to “GNOME Desktop” Environment Group, we’ll do:

sudo yum groupinstall "GNOME Desktop"

Option 2: Using --enablerepo=centos7-local command option and --disablerepo=* command option

Alternatively, use --enablerepo and --disablerepo command options accordingly.

See below example which installs all packages belonging to “Virtualization Host” Environment Group, we’ll do:

sudo yum --disablerepo=* --enablerepo=centos7-local groupinstall "Virtualization Host"

Installing single packages:

sudo yum --disablerepo=* --enablerepo=centos7-local install vim

Later on you can return the repos to original directory:

cp -r ~/repos/* /etc/yum.repos.d/

That’s all for now on how to configure CentOS 7 Local Yum repositories. Remember to copy repositories back from ~/repos/ to /etc/yum.repos.d/ directory if you need to use other YUM repositories initially configured on the server. We’ll share a similar guide for EPEL and other commonly used CentOS repositories not from OS upstream project.