← Back to Blog

Troubleshooting Kubernetes Bare Metal NFS PVs Error with Elasticsearch Helm Chart

In the world of data science, managing and deploying applications can be a complex task. Kubernetes, an open-source platform, simplifies this process by automating deployment, scaling, and management of containerized applications. However, even with Kubernetes, you may encounter some issues. One such issue is the error with Elasticsearch Helm Chart when using Kubernetes Bare Metal NFS Persistent Volumes (PVs). In this blog post, we’ll guide you through the process of troubleshooting this error.
By Saturn Cloud | | Miscellaneous

Troubleshooting Kubernetes Bare Metal NFS PVs Error with Elasticsearch Helm Chart

In the world of data science, managing and deploying applications can be a complex task. Kubernetes, an open-source platform, simplifies this process by automating deployment, scaling, and management of containerized applications. However, even with Kubernetes, you may encounter some issues. One such issue is the error with Elasticsearch Helm Chart when using Kubernetes Bare Metal NFS Persistent Volumes (PVs). In this blog post, we’ll guide you through the process of troubleshooting this error.

Introduction to Kubernetes, NFS, and Elasticsearch

Before we dive into the problem, let’s briefly discuss the key components involved.

Kubernetes is a powerful system for managing containerized applications in a clustered environment. It provides a framework to run distributed systems resiliently, scaling and recovering as needed.

Network File System (NFS) is a distributed file system protocol that allows a user on a client computer to access files over a network in a manner similar to how local storage is accessed.

Elasticsearch is a search engine based on the Lucene library. It provides a distributed, multitenant-capable, full-text search engine with an HTTP web interface and schema-free JSON documents.

Helm is a package manager for Kubernetes that allows developers and operators to more easily package, configure, and deploy applications and services onto Kubernetes clusters.

The Problem: NFS PVs Error with Elasticsearch Helm Chart

When deploying Elasticsearch using the Helm Chart on a Kubernetes cluster with NFS as the storage class for Persistent Volumes (PVs), you might encounter an error. This error typically manifests as a failure in initializing the Elasticsearch node, with the pod repeatedly crashing and entering a CrashLoopBackOff state.

Understanding the Error

The root cause of this error is often related to how Elasticsearch interacts with the underlying file system. Elasticsearch uses memory-mapped (mmap) files for improving the performance of search queries. However, NFS has some limitations with mmap, which can cause issues.

Solution: Troubleshooting Steps

Here are the steps to troubleshoot and resolve the NFS PVs error with Elasticsearch Helm Chart.

Step 1: Validate the Error

First, check the logs of the failing Elasticsearch pod. You can do this using the following command:

kubectl logs <failing-pod-name>

If you see an error message related to mmap, it confirms the issue.

Step 2: Adjust Elasticsearch Configuration

To resolve this issue, you need to adjust the Elasticsearch configuration to limit the use of mmap. You can do this by setting the node.store.allow_mmap value to false.

If you’re using the official Elasticsearch Helm Chart, you can set this value in the values.yaml file:

esConfig:
  elasticsearch.yml: |
        node.store.allow_mmap: false

Then, apply the changes by upgrading the Helm release:

helm upgrade <release-name> elastic/elasticsearch -f values.yaml

Step 3: Verify the Solution

After applying the changes, check the status of the Elasticsearch pods. They should now be running without any issues.

Conclusion

While Kubernetes, NFS, and Elasticsearch are powerful tools for managing and deploying applications, they can sometimes interact in unexpected ways. By understanding these interactions and knowing how to adjust configurations, you can resolve issues like the NFS PVs error with Elasticsearch Helm Chart.

Remember, the world of Kubernetes is vast and complex. Don’t be discouraged by these challenges. Instead, use them as opportunities to learn and grow your Kubernetes expertise.

Keywords

  • Kubernetes
  • NFS
  • Elasticsearch
  • Helm Chart
  • Persistent Volumes
  • Troubleshooting
  • Data Science
  • Distributed Systems
  • Containerized Applications
  • Network File System
  • Elasticsearch Helm Chart
  • Kubernetes Cluster
  • Kubernetes Bare Metal NFS PVs Error

About Saturn Cloud

Saturn Cloud is your all-in-one solution for data science & ML development, deployment, and data pipelines in the cloud. Spin up a notebook with 4TB of RAM, add a GPU, connect to a distributed cluster of workers, and more. Join today and get 150 hours of free compute per month.

Try Saturn Cloud Now