Rarm Nagalingam

Helping customers and the community solve problems through Open Source.

Areas of Expertise

Ansible, OpenShift, OpenStack

Recent Posts

Customizing OpenShift project creation

Customizing OpenShift project creation

I recently attended an excellent training run by Red Hat’s Global Partner Enablement Team on advanced Red Hat OpenShift management. One of the most interesting elements of the training was how to customize default project creation. This article explains how to use OpenShift’s projectRequestTemplate to add default controls for the resources that a project is allowed to consume.

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Using the Red Hat OpenShift tuned Operator for Elasticsearch

Using the Red Hat OpenShift tuned Operator for Elasticsearch

I recently assisted a client to deploy Elastic Cloud on Kubernetes (ECK) on Red Hat OpenShift 4.x. They had run into an issue where Elasticsearch would throw an error similar to:

Max virtual memory areas vm.max_map_count [65530] likely too low, increase to at least [262144]

According to the official documentation, Elasticsearch uses a mmapfs directory by default to store its indices. The default operating system limits on mmap counts are likely to be too low, which may result in out of memory exceptions. Usually, administrators would just increase the limits by running:

sysctl -w vm.max_map_count=262144

However, OpenShift uses Red Hat CoreOS for its worker nodes and, because it is an automatically updating, minimal operating system for running containerized workloads, you shouldn’t manually log on to worker nodes and make changes. This approach is unscalable and results in a worker node becoming tainted. Instead, OpenShift provides an elegant and scalable method to achieve the same via its Node Tuning Operator.

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How to configure Red Hat OpenShift 4 to use Auth0

How to configure Red Hat OpenShift 4 to use Auth0

My colleague and I recently had to stand up a Red Hat OpenShift 4 cluster for a customer to determine how difficult it would be for them to port their application. Although they could have achieved a similar outcome with CodeReady Containers, their local development machines did not have enough resources (8GB RAM minimum, which is one problem of developing on tablets).

To reduce the overhead of adding and removing users from the project during the trial, we decided to skip over the simple HTPasswd provider and use the OAuth provider backed by Auth0. We also wanted to publish our guide to make it easier for others to adopt a similar deployment.

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