Kubernetes

Memgraph can be deployed on Kubernetes. The easiest way to do that is with Helm (opens in a new tab), the package manager for Kubernetes. Helm uses a packaging format called charts (opens in a new tab). A chart is a collection of files that describe a related set of Kubernetes resources.

Currently, we prepared and released the following charts:

• Helm chart for standalone Memgraph
• Helm chart for Memgraph high availability cluster (Enterprise)
• Helm chart for Memgraph Lab

The Helm charts are published on Artifact Hub (opens in a new tab). For details on the implementation of the Helm charts, check Memgraph Helm charts repository (opens in a new tab).

Due to numerous possible use cases and deployment setups via Kubernetes, the provided Helm charts are a starting point you can modify according to your needs. This page will highlight some of the specific parts of the Helm charts that you might want to adjust.

Helm chart for standalone Memgraph

Memgraph is a stateful application (database), hence the Helm chart for standalone Memgraph (opens in a new tab) is configured to deploy Memgraph as a Kubernetes StatefulSet workload.

It will deploy a single Memgraph instance in a single pod.

Typically, when deploying a stateful application like Memgraph, a StatefulSet workload is used to ensure that each pod has a unique identity and stable network identity. When deploying Memgraph, it is also necessary to define a PersistentVolumeClaims to store the data directory (/var/lib/memgraph). This enables the data to be persisted even if the pod is restarted or deleted.

Storage configuration

By default, the Helm chart will create a PersistentVolumeClaim (PVC) for storage and logs. If the storage class for PVC is not defined, PVC will use the default one available in the cluster. The storage class can be configured in the values.yaml file. To avoid losing your data, make sure you have Retain reclaim policy. If you delete PersistentVolumeClaim without having Retain reclaim policy, you will lose your data because PersistentVolume will be deleted.

An example of a storage class for AWS EBS volumes:

storageClass:
  name: "gp2"
  provisioner: "kubernetes.io/aws-ebs"
  storageType: "gp2"
  fsType: "ext4"
  reclaimPolicy: "Retain"
  volumeBindingMode: "Immediate"

Default template for a storage class is part of the Helm chart and can be found in the repository.

More details on the configuration options can be found in the configuration section.

Secrets

The Helm chart allows you to use Kubernetes secrets to store Memgraph credentials. By default, the secrets are disabled. If you want to use secrets, you can enable them in the values.yaml file.

The secrets are prepared to work for environment variables MEMGRAPH_USER and MEMGRAPH_PASSWORD.

System configuration

The Helm chart will set the linux kernel vm.max_map_count parameter to 262144 by default to ensure Memgraph won't run into issues with memory mapping.

Installing Memgraph standalone Helm chart

To include a standalone Memgraph into your Kubernetes cluster, you need to add the repository and install Memgraph.

The steps below will work in the Minikube (opens in a new tab) environment, but you can also use them in other Kubernetes environments with minor adjustments.

Add the repository

Add the Memgraph Helm chart repository to your local Helm setup by running the following command:

helm repo add memgraph https://memgraph.github.io/helm-charts

Make sure to update the repository to fetch the latest Helm charts available:

helm repo update

Install Memgraph

To install Memgraph Helm chart, run the following command:

helm install <release-name> memgraph/memgraph

Replace <release-name> with the name of the release you chose.

Access Memgraph

Once Memgraph is installed, you can access it using the provided services and endpoints, such as various client libraries, command-line interface mgconsole or visual user interface Memgraph Lab.

Configuration options

The following table lists the configurable parameters of the Memgraph chart and their default values.

To change the default chart values, provide your own values.yaml file during the installation:

helm install <resource-name> memgraph/memgraph -f values.yaml

Default chart values can also be changed by setting the values of appropriate parameters:

helm install <resource-name> memgraph/memgraph --set <flag1>=<value1>,<flag2>=<value2>,...

memgraphConfig: 
  - "--also-log-to-stderr=true"
  - "--log-level=TRACE"

Helm chart for Memgraph high availability cluster (Enterprise)

A Helm chart for deploying Memgraph in high availability setup. This helm chart requires Memgraph Enterprise license.

Memgraph HA cluster includes 3 coordinators and 2 data instances by default. Since multiple instances are deployed, you need to have multiple workers nodes in Kubernetes to deploy the Memgraph HA cluster.

Most of the features and configurations discussed in the Helm chart for Standalone Memgraph are also applicable to the Memgraph HA Helm chart if the configuration is not specific to the standalone setup. Differences can be observed in the configuration options section.

Node affinity

Since HA Memgraph deploys multiple pods, you can control how they are distributed in the cluster.

The Memgraph HA Helm chart provides the following node affinity options:

• default: Default affinity will try to schedule the data pods and coordinator pods on the nodes where there is no other pod with the same role. If there is no such node, the pods will still be scheduled on the same node, and deployment will not fail.
• unique: This is achieved with the memgraph.affinity.unique set to true. This option will try to deploy the data pods and coordinator pods on different nodes in the cluster so that each pod is on a unique node. If there are no sufficient nodes, this deployment will fail.
• parity: This is achieved with the memgraph.affinity.parity set to true. This option will try to deploy the data pods and coordinator pods on the same node with maximum one coordinator and one data pod on the node. If there are no sufficient nodes to deploy the pods, this deployment will fail. Coordinators get scheduled first. After that, data pods are looking for the nodes with coordinators.
• nodeSelection: This is achieved with the memgraph.affinity.nodeSelection set to true. This option will try to deploy the data pods and coordinator pods on the nodes with specific labels. You can set the labels with the memgraph.affinity.dataNodeLabelValue and memgraph.affinity.coordinatorNodeLabelValue parameters. If all the nodes with labels are occupied by the pods with the same role, the deployment will fail.

Installing the Memgraph HA Helm Chart

To include Memgraph HA cluster as a part of your Kubernetes cluster, you need to add the repository and install Memgraph.

The steps below will work in the Minikube environment, but you can also use them in other Kubernetes environments with minor adjustments.

To test affinity, you can use minikube in multi-node mode.

Add the repository

Add the Memgraph Helm chart repository to your local Helm setup by running the following command:

helm repo add memgraph https://memgraph.github.io/helm-charts

Make sure to update the repository to fetch the latest Helm charts available:

helm repo update

Install Memgraph HA

Since Memgraph HA requires an Enterprise license, you need to provide the license and organization name during the installation.

helm install <release-name> memgraph/memgraph-high-availability --set memgraph.env.MEMGRAPH_ENTERPRISE_LICENSE=<your-license>,memgraph.env.MEMGRAPH_ORGANIZATION_NAME=<your-organization-name>

Replace <release-name> with a name of your choice for the release and set the Enterprise license.

Changing the default chart values

To change the default chart values, run the command with the specified set of flags:

helm install <resource-name> memgraph/memgraph-high-availability --set <flag1>=<value1>,<flag2>=<value2>,...

Or you can modify a values.yaml file and override the desired values:

helm install <resource-name> memgraph/memgraph-high-availability -f values.yaml

Configuration options

The following table lists the configurable parameters of the Memgraph chart and their default values.

For the data and coordinators sections, each item in the list has the following parameters:

The args section contains a list of arguments for the instance. The default values are the same for all instances:

- "--also-log-to-stderr"
- "--log-level=TRACE"
- "--replication-restore-state-on-startup=true"

For all available database settings, refer to the configuration settings docs.

Helm chart for Memgraph Lab

A Helm chart for deploying Memgraph Lab on Kubernetes.

Installing the Memgraph Lab Helm chart

To install the Memgraph Lab Helm chart, follow the steps below:

helm install <release-name> memgraph/memgraph-lab

Replace <release-name> with a name of your choice for the release.

Changing the default chart values

To change the default chart values, run the command with the specified set of flags:

helm install <resource-name> memgraph/memgraph-lab --set <flag1>=<value1>,<flag2>=<value2>,...

Or you can modify a values.yaml file and override the desired values:

helm install <resource-name> memgraph/memgraph-lab -f values.yaml

Configuration options

The following table lists the configurable parameters of the Memgraph Lab chart and their default values.

Memgraph Lab can be further configured with environment variables in your values.yaml file.

env:
  - name: QUICK_CONNECT_MG_HOST
    value: memgraph
  - name: QUICK_CONNECT_MG_PORT
    value: "7687"
  - name: KEEP_ALIVE_TIMEOUT_MS
    value: 65000

In case you added Nginx Ingress service or web server for a reverse proxy, update the following proxy timeout annotations to avoid potential timeouts:

proxy_read_timeout X;
proxy_connect_timeout X;
proxy_send_timeout X;

where X is the number of seconds the connection (request query) can be alive. Additionally, update the Memgraph Lab KEEP_ALIVE_TIMEOUT_MS environment variable to a higher value to ensure that Memgraph Lab stays connected to Memgraph when running queries over 65 seconds.

Refer to the Memgraph Lab documentation for details on how to connect to and interact with Memgraph.