In enterprise environments with multiple RHEL-based systems (CentOS, Fedora, etc.), having each machine download packages individually from remote repositories creates unnecessary bandwidth consumption and slows down updates. A local YUM cache server solves this by:

• Downloading packages once from the internet
• Serving them to all machines on your LAN
• Supporting multiple distribution versions (CentOS 7/8, Fedora 30+)

1. A dedicated server with sufficient storage (recommend 50GB+ for base repos)
2. Web server (Apache/Nginx) or FTP server
3. createrepo package
4. Regular sync automation

1. Install Required Packages

sudo yum install -y yum-utils createrepo httpd

2. Configure Repository Synchronization

Create a sync script (/usr/local/bin/sync_repos.sh):

#!/bin/bash
REPO_DIR="/var/www/html/repos"
REPOS=("base" "updates" "extras") # Add your required repos

for repo in "${REPOS[@]}"; do
  reposync --gpgcheck -l --repoid=${repo} --download_path=${REPO_DIR}
  createrepo -v ${REPO_DIR}/${repo} -o ${REPO_DIR}/${repo}
done

3. Set Up Cron for Automatic Updates

# Add to crontab (run daily at 2AM)
0 2 * * * /usr/local/bin/sync_repos.sh

4. Configure Web Server

Basic Apache configuration (/etc/httpd/conf.d/repos.conf):

Alias /repos /var/www/html/repos
<Directory "/var/www/html/repos">
    Options Indexes FollowSymLinks
    Require all granted
</Directory>

Create a client repo file (/etc/yum.repos.d/local.repo):

[local-base]
name=Local Base Repo
baseurl=http://yum-cache-server/repos/base
enabled=1
gpgcheck=0

[local-updates]
name=Local Updates
baseurl=http://yum-cache-server/repos/updates
enabled=1
gpgcheck=0

Version-Specific Repositories

For multiple CentOS versions (7 and 8):

reposync --gpgcheck -l --repoid=base7 --download_path=${REPO_DIR}/centos7
reposync --gpgcheck -l --repoid=base8 --download_path=${REPO_DIR}/centos8

Bandwidth Throttling

Add to sync script for controlled downloads:

reposync --gpgcheck -l --repoid=${repo} --download_path=${REPO_DIR} --limit-rate=1m

• Metadata Errors: Run createrepo --update on the repo directory
• Permission Issues: Ensure httpd_sys_content_t context on repo files
• Sync Failures: Check repository mirrors in /etc/yum.repos.d/

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In enterprise environments with multiple RHEL-based systems, a local YUM cache server significantly reduces bandwidth usage and speeds up package installations. Unlike Ubuntu's Apt-Cacher, RHEL distributions require a different approach using either yum-cron or createrepo tools.

Before setting up your cache server:

• A dedicated CentOS/RHEL 7/8/9 server with 50GB+ free space
• Root access to configure services
• Basic firewall rules for HTTP traffic (port 80/8080)
• Clients sharing the same architecture (x86_64, etc.)

First, install required packages:

yum install yum-utils createrepo httpd -y
systemctl enable --now httpd

Create the repository directory structure:

mkdir -p /var/www/html/repos/{base,updates,extras}
reposync -p /var/www/html/repos/base -r base
reposync -p /var/www/html/repos/updates -r updates
createrepo /var/www/html/repos/base
createrepo /var/www/html/repos/updates

Create a cron job to nightly sync repositories:

#!/bin/bash
reposync -p /var/www/html/repos/base -r base --download-metadata
reposync -p /var/www/html/repos/updates -r updates --download-metadata
createrepo --update /var/www/html/repos/base
createrepo --update /var/www/html/repos/updates

On client machines, create a repo file at /etc/yum.repos.d/local.repo:

[local-base]
name=Local Base
baseurl=http://yum-cache-server/repos/base
enabled=1
gpgcheck=0

[local-updates]
name=Local Updates  
baseurl=http://yum-cache-server/repos/updates
enabled=1
gpgcheck=0

For better performance:

• Use hardlink to save disk space: yum install hardlink -y
• Implement nginx instead of Apache for high traffic
• Set up failover mirrors in client configs

If clients report missing packages:

yum clean all
yum makecache
repoclosure --repo=local-base --repo=local-updates