Building a RHEL Repo Container

Sonario: you want to go off grid AND network install packages from a known release?
Solution: Move the packages from RHEL ISO images and any other packages you require into a containerised web server.

This is a bit of forced use case with many many other great solutions but we are building custom images from scratch without the internet and I thought putting the repo server into a container would be a simple from scratch tutorial which readers can quickly adapt to their own thing. Better than hello world?

Configure Repositories

This example is based on RHEL 7.6 so I register and attach a subscription before we get down to business.

subscription-manager register
subscription-manager attach --pool <pool_id>

Repos for Container-ing

subscription-manager repos --enable=rhel-7-server-rpms --enable=rhel-7-server-extras-rpms --enable=rhel-7-server-optional-rpms

Building a From Scratch Container

yum install buildah runc podman
container_spud=$(buildah from scratch)
scratchmnt=$(buildah mount $container_spud)
rpm --root $scratchmnt --initdb
yum install yum-utils
yumdownloader --destdir=/tmp redhat-release-server
rpm --root $scratchmnt -ihv /tmp/redhat-release-server*.rpm

Add Web Server with Static Content

yum install -y --installroot=$scratchmnt httpd
rm $scratchmnt/var/www/html/index.html
mkdir /mnt/rhel_installation
mount -oro,loop rhel-server-7.6-x86_64-dvd.iso /mnt/rhel_installation
mkdir -p $scratchmnt/var/www/html/rpm_repos/rhel-server-7.6-x86_64-dvd
cp -av  /mnt/rhel_installation $scratchmnt/var/www/html/rpm_repos/rhel-server-7.6-x86_64-dvd

Create more directories and use the createrepo command from the createrepo package to turn a directory of RPMs into a proper YUM repository.

createrepo <directory>

Turn the buildah container into image for sharing and deployment.

buildah config --cmd "/usr/sbin/httpd -DFOREGROUND" $container_spud
buildah config --port 80/tcp $container_spud
buildah commit $container_spud spud_content_server:latest
podman images

Launch the RHEL Content Container.

podman run -p 8080:80 -d --name httpd-server <image_id>

Web browse to: http://<container_host>:8080/rpm_repos/rhel-server-7.6-x86_64-dvd/

RHEL hosts wanting to use the repository need a repo file in /etc/yum.repos.d/ similar to the following:

[RHEL76InstallMedia]  
name=Red Hat Enterprise Linux 7.6  
baseurl = http://<container_host>:8080/rpm_repos/rhel-server-7.6-x86_64-dvd/
metadata_expire=-1  
gpgcheck=0  

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System Monitoring with PCP (Performance Co-pilot)

Configure Repositories

This example is based on RHEL 7.6 so I register and attach a subscription before we get down to business.

subscription-manager register
subscription-manager attach --pool <pool_id>

Install and Start Monitoring

The monitoring services start automatically upon installation but have them start at each boot you have to enable their services.

yum install pcp-zeroconf
systemctl enable pmcd pmlogger

Live Text Based Monitoring

Command	Description
pcp atop	Similar to “top”.
pcp atopsar	Similar to “sar”.
pmrep -i eth0 -v network.interface.out	Network outbound.

Live Web Based Monitoring

yum install pcp-webapi pcp-webjs
firewall-cmd --add-port 44323/tcp --permanent
firewall-cmd --reload
systemctl enable pmwebd
systemctl start pmwebd

Web browse to: http://<host>:44323/
Explore the various web applications provided on the jump page. There are many and the following image shows “Vector”.

Copy logs for Later Analysis

Archive the PCP logs for attaching to your Red Hat support ticket.

tar cvJf pcp-logs_$(hostname)_$(date +%Y%m%d).tar.xz /var/log/pcp/

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