Well, why not? But the compelling reason for me is that I need more resources to run some of the expansive examples with OpenShift. My Macbook is limited to 16 GB RAM so I don't have enough to allocate to a minishift virtual machine. I suppose I could host my demos in the cloud but that isn't always feasible for me and I'm no fan of the monthly bill. This solution gives me a portable environment to take anywhere to show off OCP features. Plus it looks cool.
Use these instructions, adapted from Grant Shipley's excellent OpenShift Origin instructions, to run OpenShift Container Platform on an Intel NUC.
The specific hardware is an Intel NUC mini PC kit NUC6i7KYK (e.g. Skull Canyon).
| Feature | Description |
|---|---|
| CPU | Intel 2.6 GHz 4-Core i7 6700HQ |
| Memory | Crucial 32GB DDR4 2133 |
| Graphics | Intel Iris Pro Graphics 580 |
| SSD | Samsung 850 EVO - 500GB |
Install RHEL 7.6 using the minimal package set. Create the following mount points on the disk. The sizes are scaled for the 500 GB SSD.
- /boot with 2 GiB
- /boot/efi with 1 GiB
- / with 358 GiB
- swap with 4 GiB
This leaves just over 100 GiB for the docker-vg volume group which will be created later. Make sure to set the root password and also create an unprivileged user (with sudo privileges). In my configuration, I also disabled the onboard WiFi interface.
NB: DO NOT SET THE HOSTNAME WHEN INSTALLING RHEL. This can cause name resolution issues for the internal docker registry that are still being investigated.
I want to make this portable to any site for demonstrations with the ability to have a predictable IP address for the NUC. To do that, I purchased a small WiFi travel router to enable a LAN for my NUC and my laptop and to provide a connection to the outside world. These instructions describe how I did that.
Edit the install.conf and update the parameters as necessary. At
a minimum, you'll need to update RHSM_USER and RHSM_PASS to
match your credentials for the Red Hat Customer
Portal. Optionally, you can asign the
POOL_ID to match one of your entitlements.
With OCP 3.11, the Red Hat container registry
now restricts pulling images to authenticated users. To get your
credentials, go to the Red Hat container registry
and click on the Service Accounts link in the center right of the
page. Scroll until you find your account or click New Service Account to create one. Click on your service account. Make sure
the Token Information tab is selected and copy your username and
password to the parameters OREG_USER and OREG_PASS, respectively,
in the install.conf file. Make sure the username includes the
random number, the vertical bar, and the service account name.
Run the following script as root to prepare the server for installs. This script registers the system and creates the docker-vg volume group.
./prep-server.sh
The system will reboot once this script completes.
Run the following script as root to install the server. This script installs prerequisites, runs the install, and then creates a cluster admin user as well as an unprivileged user.
./install-server.sh
Unless you changed the parameters in install.conf, the following
username/passwords are created:
admin/admindeveloper/developer
Run the following script as root to create one hundred 10 GiB
persistent volumes. The persistent volume directories are under
/mnt/data.
./create-pvs.sh
To upgrade to the latest version of OpenShift, follow the upgrade
instructions in the official docs. As a help, three scripts are
provided, but always check to make sure they match the instuctions in
the OpenShift documentation. Edit install.conf and make sure that
VERSION is correct. Then run the script:
./upgrade-server.sh
Reboot the computer. When the system is back up, run:
./upgrade-logging.sh
./upgrade-metrics.sh
This will work with a VirtualBox VM on OSX. In this configuration,
the host is providing stable DNS name resolution for the domain
<FIXED IP>.nip.io. The parameter <FIXED IP> is whatever static
IP address was assigned to the OCP all-in-one instance.
Make sure that dnsmasq is running and there is a stable wildcard
resolution for <FIXED IP>.nip.io. On OSX, you can use the resolver
facility by doing creating a file named /etc/resolver/nip.io with
the contents:
domain nip.io
nameserver 127.0.0.1
Then use brew to install and run dnsmasq. First, install it using:
brew install dnsmasq
Next, create the file /usr/local/etc/dnsmasq.conf with the contents:
address=/.<FIXED IP>.nip.io/<FIXED IP>
listen-address=127.0.0.1
Finally, start dnsmasq using:
sudo brew services start dnsmasq
This example must first be built with internet connectivity so that all the required images are pulled and added to the local docker registry. With internet connectivity, do the following:
oc new-app php~https://github.com/rlucente-se-jboss/phpmysqldemo.git --name myphp
oc expose svc/myphp
Once the application is fully up and running, and possibly with an added database via the web console, you can then delete the project and application using:
oc delete all --all -n demo
oc delete project demo
Then remove the pre-built docker image using:
ssh root@<FIXED IP>
docker rmi -f $(docker images | grep myphp | awk '{print $3}')
Finally, on your host, get a local copy of the git repository:
git clone https://github.com/rlucente-se-jboss/phpmysqldemo.git
With the internal docker registry now pre-populated, you can create the image using:
cd /path/to/phpmysqldemo
oc login -u developer -p developer console.<FIXED IP>.nip.io:8443
oc new-project demo
oc new-build --binary --image-stream php --name myphp
oc start-build myphp --from-dir=.
When the build completes, issue: oc new-app myphp oc expose svc/myphp
To connect the application to the MySQL instance, use: oc set env dc/myphp MYSQL_SERVICE_HOST=mysql.demo.svc.cluster.local MYSQL_SERVICE_PORT=3306 MYSQL_SERVICE_DATABASE=myphp MYSQL_SERVICE_USERNAME=myphp MYSQL_SERVICE_PASSWORD=myphp