Bitnami package for Etcd

etcd is a distributed key-value store designed to securely store data across a cluster. etcd is widely used in production on account of its reliability, fault-tolerance and ease of use.

Overview of Etcd

Trademarks: This software listing is packaged by Bitnami. The respective trademarks mentioned in the offering are owned by the respective companies, and use of them does not imply any affiliation or endorsement.

TL;DR

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/etcd

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository.

Introduction

This chart bootstraps a etcd deployment on a Kubernetes cluster using the Helm package manager.

Bitnami charts can be used with Kubeapps for deployment and management of Helm Charts in clusters.

Prerequisites

  • Kubernetes 1.23+
  • Helm 3.8.0+
  • PV provisioner support in the underlying infrastructure

Installing the Chart

To install the chart with the release name my-release:

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/etcd

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

These commands deploy etcd on the Kubernetes cluster in the default configuration. The Parameters section lists the parameters that can be configured during installation.

Tip: List all releases using helm list

Configuration and installation details

Resource requests and limits

Bitnami charts allow setting resource requests and limits for all containers inside the chart deployment. These are inside the resources value (check parameter table). Setting requests is essential for production workloads and these should be adapted to your specific use case.

To make this process easier, the chart contains the resourcesPreset values, which automatically sets the resources section according to different presets. Check these presets in the bitnami/common chart. However, in production workloads using resourcePreset is discouraged as it may not fully adapt to your specific needs. Find more information on container resource management in the official Kubernetes documentation.

Rolling VS Immutable tags

It is strongly recommended to use immutable tags in a production environment. This ensures your deployment does not change automatically if the same tag is updated with a different image.

Bitnami will release a new chart updating its containers if a new version of the main container, significant changes, or critical vulnerabilities exist.

Cluster configuration

The Bitnami etcd chart can be used to bootstrap an etcd cluster, easy to scale and with available features to implement disaster recovery. It uses static discovery configured via environment variables to bootstrap the etcd cluster. Based on the number of initial replicas, and using the A records added to the DNS configuration by the headless service, the chart can calculate every advertised peer URL.

The chart makes use of some extra elements offered by Kubernetes to ensure the bootstrapping is successful:

  • It sets a “Parallel” Pod Management Policy. This is critical, since all the etcd replicas should be created simultaneously to guarantee they can find each other.
  • It records “not ready” pods in the DNS, so etcd replicas are reachable using their associated FQDN before they’re actually ready.

Learn more about etcd discovery, Pod Management Policies and recording “not ready” pods.

Here is an example of the environment configuration bootstrapping an etcd cluster with 3 replicas:

Member Variable Value
0 ETCD_NAME etcd-0
0 ETCD_INITIAL_ADVERTISE_PEER_URLS http://etcd-0.etcd-headless.default.svc.cluster.local:2380
——— ———————————- ——————————————————————————————————————————————————————————————————-
1 ETCD_NAME etcd-1
1 ETCD_INITIAL_ADVERTISE_PEER_URLS http://etcd-1.etcd-headless.default.svc.cluster.local:2380
——— ———————————- ——————————————————————————————————————————————————————————————————-
2 ETCD_NAME etcd-2
2 ETCD_INITIAL_ADVERTISE_PEER_URLS http://etcd-2.etcd-headless.default.svc.cluster.local:2380
——— ———————————- ——————————————————————————————————————————————————————————————————-
* ETCD_INITIAL_CLUSTER_STATE new
* ETCD_INITIAL_CLUSTER_TOKEN etcd-cluster-k8s
* ETCD_INITIAL_CLUSTER etcd-0=http://etcd-0.etcd-headless.default.svc.cluster.local:2380,etcd-1=http://etcd-1.etcd-headless.default.svc.cluster.local:2380,etcd-2=http://etcd-2.etcd-headless.default.svc.cluster.local:2380

The probes (readiness & liveness) are delayed 60 seconds by default, to give the etcd replicas time to start and find each other. After that period, the etcdctl endpoint health command is used to periodically perform health checks on every replica.

Scalability

The Bitnami etcd chart uses etcd reconfiguration operations to add/remove members of the cluster during scaling.

When scaling down, a “pre-stop” lifecycle hook is used to ensure that the etcdctl member remove command is executed. The hook stores the output of this command in the persistent volume attached to the etcd pod. This hook is also executed when the pod is manually removed using the kubectl delete pod command or rescheduled by Kubernetes for any reason. This implies that the cluster can be scaled up/down without human intervention.

Here is an example to explain how this works:

  1. An etcd cluster with three members running on a three-nodes Kubernetes cluster is bootstrapped.
  2. After a few days, the cluster administrator decides to upgrade the kernel on one of the cluster nodes. To do so, the administrator drains the node. Pods running on that node are rescheduled to a different one.
  3. During the pod eviction process, the “pre-stop” hook removes the etcd member from the cluster. Thus, the etcd cluster is scaled down to only two members.
  4. Once the pod is scheduled on another node and initialized, the etcd member is added again to the cluster using the etcdctl member add command. Thus, the etcd cluster is scaled up to three replicas.

If, for whatever reason, the “pre-stop” hook fails at removing the member, the initialization logic is able to detect that something went wrong by checking the etcdctl member remove command output that was stored in the persistent volume. It then uses the etcdctl member update command to add back the member. In this case, the cluster isn’t automatically scaled down/up while the pod is recovered. Therefore, when other members attempt to connect to the pod, it may cause warnings or errors like the one below:

E | rafthttp: failed to dial XXXXXXXX on stream Message (peer XXXXXXXX failed to find local node YYYYYYYYY)
I | rafthttp: peer XXXXXXXX became inactive (message send to peer failed)
W | rafthttp: health check for peer XXXXXXXX could not connect: dial tcp A.B.C.D:2380: i/o timeout

Learn more about etcd runtime configuration and how to safely drain a Kubernetes node.

Cluster updates

When updating the etcd StatefulSet (such as when upgrading the chart version via the helm upgrade command), every pod must be replaced following the StatefulSet update strategy.

The chart uses a “RollingUpdate” strategy by default and with default Kubernetes values. In other words, it updates each Pod, one at a time, in the same order as Pod termination (from the largest ordinal to the smallest). It will wait until an updated Pod is “Running” and “Ready” prior to updating its predecessor.

Learn more about StatefulSet update strategies.

Disaster recovery

If, for whatever reason, (N-1)/2 members of the cluster fail and the “pre-stop” hooks also fail at removing them from the cluster, the cluster disastrously fails, irrevocably losing quorum. Once quorum is lost, the cluster cannot reach consensus and therefore cannot continue accepting updates. Under this circumstance, the only possible solution is usually to restore the cluster from a snapshot.

IMPORTANT: All members should restore using the same snapshot.

The Bitnami etcd chart solves this problem by optionally offering a Kubernetes cron job that periodically snapshots the keyspace and stores it in a RWX volume. In case the cluster disastrously fails, the pods will automatically try to restore it using the last avalable snapshot.

Learn how to enable this disaster recovery feature.

The chart also sets by default a “soft” Pod AntiAffinity to reduce the risk of the cluster failing disastrously.

Learn more about etcd recovery, Kubernetes cron jobs and pod affinity and anti-affinity

Enable security for etcd

The etcd chart can be configured with Role-based access control and TLS encryption to improve its security.

Configure RBAC

In order to enable Role-Based Access Control for etcd, set the following parameters:

auth.rbac.enabled=true
auth.rbac.rootPassword=ETCD_ROOT_PASSWORD

These parameters create a root user with an associate root role with access to everything. The remaining users will use the guest role and won’t have permissions to do anything.

Configure TLS for server-to-server communications

In order to enable secure transport between peer nodes deploy the helm chart with these options:

auth.peer.secureTransport=true
auth.peer.useAutoTLS=true

Configure certificates for client communication

In order to enable secure transport between client and server, create a secret containing the certificate and key files and the CA used to sign the client certificates. In this case, create the secret and then deploy the chart with these options:

auth.client.secureTransport=true
auth.client.enableAuthentication=true
auth.client.existingSecret=etcd-client-certs

Learn more about the etcd security model and how to generate self-signed certificates for etcd.

Enable disaster recovery features

The Bitnami etcd Helm chart supports automatic disaster recovery by periodically snapshotting the keyspace. If the cluster permanently loses more than (N-1)/2 members, it tries to recover the cluster from a previous snapshot.

Enable this feature with the following parameters:

persistence.enabled=true
disasterRecovery.enabled=true
disasterRecovery.pvc.size=2Gi
disasterRecovery.pvc.storageClassName=nfs

If the startFromSnapshot.* parameters are used at the same time as the disasterRecovery.* parameters, the PVC provided via the startFromSnapshot.existingClaim parameter will be used to store the periodical snapshots.

NOTE: The disaster recovery feature requires volumes with ReadWriteMany access mode.

Backup and restore the etcd keyspace

Two different approaches are available to back up and restore this Helm Chart:

  • Back up the data from the source deployment and restore it in a new deployment using etcd’s built-in backup/restore tools.
  • Back up the persistent volumes from the source deployment and attach them to a new deployment using Velero, a Kubernetes backup/restore tool.

Method 1: Backup and restore data using etcd’s built-in tools

This method involves the following steps:

  • Use the etcdctl tool to create a snapshot of the data in the source cluster.
  • Make the snapshot available in a Kubernetes PersistentVolumeClaim (PVC) that supports ReadWriteMany access (for example, a PVC created with the NFS storage class)
  • Restore the data snapshot in a new cluster using the <%= variable :catalog_name, :platform %> etcd Helm chart’s startFromSnapshot.existingClaim and startFromSnapshot.snapshotFilename parameters to define the source PVC and source filename for the snapshot.

NOTE: Under this approach, it is important to create the new deployment on the destination cluster using the same credentials as the original deployment on the source cluster.

Method 2: Back up and restore persistent data volumes

This method involves copying the persistent data volumes for the etcd nodes and reusing them in a new deployment with Velero, an open source Kubernetes backup/restore tool. This method is only suitable when:

This method involves the following steps:

  • Install Velero on the source and destination clusters.
  • Use Velero to back up the PersistentVolumes (PVs) used by the etcd deployment on the source cluster.
  • Use Velero to restore the backed-up PVs on the destination cluster.
  • Create a new etcd deployment on the destination cluster with the same deployment name, credentials and other parameters as the original. This new deployment will use the restored PVs and hence the original data.

Exposing etcd metrics

The metrics exposed by etcd can be exposed to be scraped by Prometheus. Metrics can be scraped from within the cluster using any of the following approaches:

  • Adding the required annotations for Prometheus to discover the metrics endpoints, as in the example below:
podAnnotations:
  prometheus.io/scrape: "true"
  prometheus.io/path: "/metrics/cluster"
  prometheus.io/port: "9000"

If metrics are to be scraped from outside the cluster, the Kubernetes API proxy can be utilized to access the endpoint.

Using custom configuration

In order to use custom configuration parameters, two options are available:

  • Using environment variables: etcd allows setting environment variables that map to configuration settings. In order to set extra environment variables, you can use the extraEnvVars property. Alternatively, you can use a ConfigMap or a Secret with the environment variables using the extraEnvVarsCM or the extraEnvVarsSecret properties.
extraEnvVars:
  - name: ETCD_AUTO_COMPACTION_RETENTION
    value: "0"
  - name: ETCD_HEARTBEAT_INTERVAL
    value: "150"
  • Using a custom etcd.conf.yml: The etcd chart allows mounting a custom etcd.conf.yml file as ConfigMap. In order to so, you can use the configuration property. Alternatively, you can use an existing ConfigMap using the existingConfigmap parameter.

Auto Compaction

Since etcd keeps an exact history of its keyspace, this history should be periodically compacted to avoid performance degradation and eventual storage space exhaustion. Compacting the keyspace history drops all information about keys superseded prior to a given keyspace revision. The space used by these keys then becomes available for additional writes to the keyspace.

autoCompactionMode, by default periodic. Valid values: “periodic”, “revision”.

  • ‘periodic’ for duration based retention, defaulting to hours if no time unit is provided (e.g. “5m”).
  • ‘revision’ for revision number based retention. autoCompactionRetention for mvcc key value store in hour, by default 0, means disabled.

You can enable auto compaction by using following parameters:

autoCompactionMode=periodic
autoCompactionRetention=10m

Sidecars and Init Containers

If you have a need for additional containers to run within the same pod as the etcd app (e.g. an additional metrics or logging exporter), you can do so via the sidecars config parameter. Simply define your container according to the Kubernetes container spec.

sidecars:
  - name: your-image-name
    image: your-image
    imagePullPolicy: Always
    ports:
      - name: portname
       containerPort: 1234

Similarly, you can add extra init containers using the initContainers parameter.

initContainers:
  - name: your-image-name
    image: your-image
    imagePullPolicy: Always
    ports:
      - name: portname
        containerPort: 1234

Deploying extra resources

There are cases where you may want to deploy extra objects, such a ConfigMap containing your app’s configuration or some extra deployment with a micro service used by your app. For covering this case, the chart allows adding the full specification of other objects using the extraDeploy parameter.

Setting Pod’s affinity

This chart allows you to set your custom affinity using the affinity parameter. Find more information about Pod’s affinity in the kubernetes documentation.

As an alternative, you can use of the preset configurations for pod affinity, pod anti-affinity, and node affinity available at the bitnami/common chart. To do so, set the podAffinityPreset, podAntiAffinityPreset, or nodeAffinityPreset parameters.

Persistence

The Bitnami etcd image stores the etcd data at the /bitnami/etcd path of the container. Persistent Volume Claims are used to keep the data across statefulsets.

The chart mounts a Persistent Volume volume at this location. The volume is created using dynamic volume provisioning by default. An existing PersistentVolumeClaim can also be defined for this purpose.

If you encounter errors when working with persistent volumes, refer to our troubleshooting guide for persistent volumes.

Parameters

Global parameters

Name Description Value
global.imageRegistry Global Docker image registry ""
global.imagePullSecrets Global Docker registry secret names as an array []
global.storageClass Global StorageClass for Persistent Volume(s) ""
global.compatibility.openshift.adaptSecurityContext Adapt the securityContext sections of the deployment to make them compatible with Openshift restricted-v2 SCC: remove runAsUser, runAsGroup and fsGroup and let the platform use their allowed default IDs. Possible values: auto (apply if the detected running cluster is Openshift), force (perform the adaptation always), disabled (do not perform adaptation) auto

Common parameters

Name Description Value
kubeVersion Force target Kubernetes version (using Helm capabilities if not set) ""
nameOverride String to partially override common.names.fullname template (will maintain the release name) ""
fullnameOverride String to fully override common.names.fullname template ""
commonLabels Labels to add to all deployed objects {}
commonAnnotations Annotations to add to all deployed objects {}
clusterDomain Default Kubernetes cluster domain cluster.local
extraDeploy Array of extra objects to deploy with the release []
diagnosticMode.enabled Enable diagnostic mode (all probes will be disabled and the command will be overridden) false
diagnosticMode.command Command to override all containers in the deployment ["sleep"]
diagnosticMode.args Args to override all containers in the deployment ["infinity"]

etcd parameters

Name Description Value
image.registry etcd image registry REGISTRY_NAME
image.repository etcd image name REPOSITORY_NAME/etcd
image.digest etcd image digest in the way sha256:aa…. Please note this parameter, if set, will override the tag ""
image.pullPolicy etcd image pull policy IfNotPresent
image.pullSecrets etcd image pull secrets []
image.debug Enable image debug mode false
auth.rbac.create Switch to enable RBAC authentication true
auth.rbac.allowNoneAuthentication Allow to use etcd without configuring RBAC authentication true
auth.rbac.rootPassword Root user password. The root user is always root ""
auth.rbac.existingSecret Name of the existing secret containing credentials for the root user ""
auth.rbac.existingSecretPasswordKey Name of key containing password to be retrieved from the existing secret ""
auth.token.enabled Enables token authentication true
auth.token.type Authentication token type. Allowed values: ‘simple’ or ‘jwt’ jwt
auth.token.privateKey.filename Name of the file containing the private key for signing the JWT token jwt-token.pem
auth.token.privateKey.existingSecret Name of the existing secret containing the private key for signing the JWT token ""
auth.token.signMethod JWT token sign method RS256
auth.token.ttl JWT token TTL 10m
auth.client.secureTransport Switch to encrypt client-to-server communications using TLS certificates false
auth.client.useAutoTLS Switch to automatically create the TLS certificates false
auth.client.existingSecret Name of the existing secret containing the TLS certificates for client-to-server communications ""
auth.client.enableAuthentication Switch to enable host authentication using TLS certificates. Requires existing secret false
auth.client.certFilename Name of the file containing the client certificate cert.pem
auth.client.certKeyFilename Name of the file containing the client certificate private key key.pem
auth.client.caFilename Name of the file containing the client CA certificate ""
auth.peer.secureTransport Switch to encrypt server-to-server communications using TLS certificates false
auth.peer.useAutoTLS Switch to automatically create the TLS certificates false
auth.peer.existingSecret Name of the existing secret containing the TLS certificates for server-to-server communications ""
auth.peer.enableAuthentication Switch to enable host authentication using TLS certificates. Requires existing secret false
auth.peer.certFilename Name of the file containing the peer certificate cert.pem
auth.peer.certKeyFilename Name of the file containing the peer certificate private key key.pem
auth.peer.caFilename Name of the file containing the peer CA certificate ""
autoCompactionMode Auto compaction mode, by default periodic. Valid values: “periodic”, “revision”. ""
autoCompactionRetention Auto compaction retention for mvcc key value store in hour, by default 0, means disabled ""
initialClusterState Initial cluster state. Allowed values: ‘new’ or ‘existing’ ""
initialClusterToken Initial cluster token. Can be used to protect etcd from cross-cluster-interaction, which might corrupt the clusters. etcd-cluster-k8s
logLevel Sets the log level for the etcd process. Allowed values: ‘debug’, ‘info’, ‘warn’, ‘error’, ‘panic’, ‘fatal’ info
maxProcs Limits the number of operating system threads that can execute user-level ""
removeMemberOnContainerTermination Use a PreStop hook to remove the etcd members from the etcd cluster on container termination true
configuration etcd configuration. Specify content for etcd.conf.yml ""
existingConfigmap Existing ConfigMap with etcd configuration ""
extraEnvVars Extra environment variables to be set on etcd container []
extraEnvVarsCM Name of existing ConfigMap containing extra env vars ""
extraEnvVarsSecret Name of existing Secret containing extra env vars ""
command Default container command (useful when using custom images) []
args Default container args (useful when using custom images) []

etcd statefulset parameters

Name Description Value
replicaCount Number of etcd replicas to deploy 1
updateStrategy.type Update strategy type, can be set to RollingUpdate or OnDelete. RollingUpdate
podManagementPolicy Pod management policy for the etcd statefulset Parallel
automountServiceAccountToken Mount Service Account token in pod false
hostAliases etcd pod host aliases []
lifecycleHooks Override default etcd container hooks {}
containerPorts.client Client port to expose at container level 2379
containerPorts.peer Peer port to expose at container level 2380
containerPorts.metrics Metrics port to expose at container level when metrics.useSeparateEndpoint is true 9090
podSecurityContext.enabled Enabled etcd pods’ Security Context true
podSecurityContext.fsGroupChangePolicy Set filesystem group change policy Always
podSecurityContext.sysctls Set kernel settings using the sysctl interface []
podSecurityContext.supplementalGroups Set filesystem extra groups []
podSecurityContext.fsGroup Set etcd pod’s Security Context fsGroup 1001
containerSecurityContext.enabled Enabled etcd containers’ Security Context true
containerSecurityContext.seLinuxOptions Set SELinux options in container {}
containerSecurityContext.runAsUser Set etcd containers’ Security Context runAsUser 1001
containerSecurityContext.runAsGroup Set etcd containers’ Security Context runAsUser 1001
containerSecurityContext.runAsNonRoot Set Controller container’s Security Context runAsNonRoot true
containerSecurityContext.privileged Set primary container’s Security Context privileged false
containerSecurityContext.allowPrivilegeEscalation Set primary container’s Security Context allowPrivilegeEscalation false
containerSecurityContext.readOnlyRootFilesystem Set container’s Security Context readOnlyRootFilesystem true
containerSecurityContext.capabilities.drop List of capabilities to be dropped ["ALL"]
containerSecurityContext.seccompProfile.type Set container’s Security Context seccomp profile RuntimeDefault
resourcesPreset Set container resources according to one common preset (allowed values: none, nano, micro, small, medium, large, xlarge, 2xlarge). This is ignored if resources is set (resources is recommended for production). micro
resources Set container requests and limits for different resources like CPU or memory (essential for production workloads) {}
livenessProbe.enabled Enable livenessProbe true
livenessProbe.initialDelaySeconds Initial delay seconds for livenessProbe 60
livenessProbe.periodSeconds Period seconds for livenessProbe 30
livenessProbe.timeoutSeconds Timeout seconds for livenessProbe 5
livenessProbe.failureThreshold Failure threshold for livenessProbe 5
livenessProbe.successThreshold Success threshold for livenessProbe 1
readinessProbe.enabled Enable readinessProbe true
readinessProbe.initialDelaySeconds Initial delay seconds for readinessProbe 60
readinessProbe.periodSeconds Period seconds for readinessProbe 10
readinessProbe.timeoutSeconds Timeout seconds for readinessProbe 5
readinessProbe.failureThreshold Failure threshold for readinessProbe 5
readinessProbe.successThreshold Success threshold for readinessProbe 1
startupProbe.enabled Enable startupProbe false
startupProbe.initialDelaySeconds Initial delay seconds for startupProbe 0
startupProbe.periodSeconds Period seconds for startupProbe 10
startupProbe.timeoutSeconds Timeout seconds for startupProbe 5
startupProbe.failureThreshold Failure threshold for startupProbe 60
startupProbe.successThreshold Success threshold for startupProbe 1
customLivenessProbe Override default liveness probe {}
customReadinessProbe Override default readiness probe {}
customStartupProbe Override default startup probe {}
extraVolumes Optionally specify extra list of additional volumes for etcd pods []
extraVolumeMounts Optionally specify extra list of additional volumeMounts for etcd container(s) []
extraVolumeClaimTemplates Optionally specify extra list of additional volumeClaimTemplates for etcd container(s) []
initContainers Add additional init containers to the etcd pods []
sidecars Add additional sidecar containers to the etcd pods []
podAnnotations Annotations for etcd pods {}
podLabels Extra labels for etcd pods {}
podAffinityPreset Pod affinity preset. Ignored if affinity is set. Allowed values: soft or hard ""
podAntiAffinityPreset Pod anti-affinity preset. Ignored if affinity is set. Allowed values: soft or hard soft
nodeAffinityPreset.type Node affinity preset type. Ignored if affinity is set. Allowed values: soft or hard ""
nodeAffinityPreset.key Node label key to match. Ignored if affinity is set. ""
nodeAffinityPreset.values Node label values to match. Ignored if affinity is set. []
affinity Affinity for pod assignment {}
nodeSelector Node labels for pod assignment {}
tolerations Tolerations for pod assignment []
terminationGracePeriodSeconds Seconds the pod needs to gracefully terminate ""
schedulerName Name of the k8s scheduler (other than default) ""
priorityClassName Name of the priority class to be used by etcd pods ""
runtimeClassName Name of the runtime class to be used by pod(s) ""
shareProcessNamespace Enable shared process namespace in a pod. false
topologySpreadConstraints Topology Spread Constraints for pod assignment []
persistentVolumeClaimRetentionPolicy.enabled Controls if and how PVCs are deleted during the lifecycle of a StatefulSet false
persistentVolumeClaimRetentionPolicy.whenScaled Volume retention behavior when the replica count of the StatefulSet is reduced Retain
persistentVolumeClaimRetentionPolicy.whenDeleted Volume retention behavior that applies when the StatefulSet is deleted Retain

Traffic exposure parameters

Name Description Value
service.type Kubernetes Service type ClusterIP
service.enabled create second service if equal true true
service.clusterIP Kubernetes service Cluster IP ""
service.ports.client etcd client port 2379
service.ports.peer etcd peer port 2380
service.ports.metrics etcd metrics port when metrics.useSeparateEndpoint is true 9090
service.nodePorts.client Specify the nodePort client value for the LoadBalancer and NodePort service types. ""
service.nodePorts.peer Specify the nodePort peer value for the LoadBalancer and NodePort service types. ""
service.nodePorts.metrics Specify the nodePort metrics value for the LoadBalancer and NodePort service types. The metrics port is only exposed when metrics.useSeparateEndpoint is true. ""
service.clientPortNameOverride etcd client port name override ""
service.peerPortNameOverride etcd peer port name override ""
service.metricsPortNameOverride etcd metrics port name override. The metrics port is only exposed when metrics.useSeparateEndpoint is true. ""
service.loadBalancerIP loadBalancerIP for the etcd service (optional, cloud specific) ""
service.loadBalancerSourceRanges Load Balancer source ranges []
service.externalIPs External IPs []
service.externalTrafficPolicy %%MAIN_CONTAINER_NAME%% service external traffic policy Cluster
service.extraPorts Extra ports to expose (normally used with the sidecar value) []
service.annotations Additional annotations for the etcd service {}
service.sessionAffinity Session Affinity for Kubernetes service, can be “None” or “ClientIP” None
service.sessionAffinityConfig Additional settings for the sessionAffinity {}
service.headless.annotations Annotations for the headless service. {}

Persistence parameters

Name Description Value
persistence.enabled If true, use a Persistent Volume Claim. If false, use emptyDir. true
persistence.storageClass Persistent Volume Storage Class ""
persistence.annotations Annotations for the PVC {}
persistence.labels Labels for the PVC {}
persistence.accessModes Persistent Volume Access Modes ["ReadWriteOnce"]
persistence.size PVC Storage Request for etcd data volume 8Gi
persistence.selector Selector to match an existing Persistent Volume {}

Volume Permissions parameters

Name Description Value
volumePermissions.enabled Enable init container that changes the owner and group of the persistent volume(s) mountpoint to runAsUser:fsGroup false
volumePermissions.image.registry Init container volume-permissions image registry REGISTRY_NAME
volumePermissions.image.repository Init container volume-permissions image name REPOSITORY_NAME/os-shell
volumePermissions.image.digest Init container volume-permissions image digest in the way sha256:aa…. Please note this parameter, if set, will override the tag ""
volumePermissions.image.pullPolicy Init container volume-permissions image pull policy IfNotPresent
volumePermissions.image.pullSecrets Specify docker-registry secret names as an array []
volumePermissions.resourcesPreset Set container resources according to one common preset (allowed values: none, nano, micro, small, medium, large, xlarge, 2xlarge). This is ignored if volumePermissions.resources is set (volumePermissions.resources is recommended for production). nano
volumePermissions.resources Set container requests and limits for different resources like CPU or memory (essential for production workloads) {}

Network Policy parameters

Name Description Value
networkPolicy.enabled Enable creation of NetworkPolicy resources true
networkPolicy.allowExternal Don’t require client label for connections true
networkPolicy.allowExternalEgress Allow the pod to access any range of port and all destinations. true
networkPolicy.extraIngress Add extra ingress rules to the NetworkPolicy []
networkPolicy.extraEgress Add extra ingress rules to the NetworkPolicy []
networkPolicy.ingressNSMatchLabels Labels to match to allow traffic from other namespaces {}
networkPolicy.ingressNSPodMatchLabels Pod labels to match to allow traffic from other namespaces {}

Metrics parameters

Name Description Value
metrics.enabled Expose etcd metrics false
metrics.useSeparateEndpoint Use a separate endpoint for exposing metrics false
metrics.podAnnotations Annotations for the Prometheus metrics on etcd pods {}
metrics.podMonitor.enabled Create PodMonitor Resource for scraping metrics using PrometheusOperator false
metrics.podMonitor.namespace Namespace in which Prometheus is running monitoring
metrics.podMonitor.interval Specify the interval at which metrics should be scraped 30s
metrics.podMonitor.scrapeTimeout Specify the timeout after which the scrape is ended 30s
metrics.podMonitor.additionalLabels Additional labels that can be used so PodMonitors will be discovered by Prometheus {}
metrics.podMonitor.scheme Scheme to use for scraping http
metrics.podMonitor.tlsConfig TLS configuration used for scrape endpoints used by Prometheus {}
metrics.podMonitor.relabelings Prometheus relabeling rules []
metrics.prometheusRule.enabled Create a Prometheus Operator PrometheusRule (also requires metrics.enabled to be true and metrics.prometheusRule.rules) false
metrics.prometheusRule.namespace Namespace for the PrometheusRule Resource (defaults to the Release Namespace) ""
metrics.prometheusRule.additionalLabels Additional labels that can be used so PrometheusRule will be discovered by Prometheus {}
metrics.prometheusRule.rules Prometheus Rule definitions []

Snapshotting parameters

Name Description Value
startFromSnapshot.enabled Initialize new cluster recovering an existing snapshot false
startFromSnapshot.existingClaim Existing PVC containing the etcd snapshot ""
startFromSnapshot.snapshotFilename Snapshot filename ""
disasterRecovery.enabled Enable auto disaster recovery by periodically snapshotting the keyspace false
disasterRecovery.cronjob.schedule Schedule in Cron format to save snapshots */30 * * * *
disasterRecovery.cronjob.historyLimit Number of successful finished jobs to retain 1
disasterRecovery.cronjob.snapshotHistoryLimit Number of etcd snapshots to retain, tagged by date 1
disasterRecovery.cronjob.snapshotsDir Directory to store snapshots /snapshots
disasterRecovery.cronjob.podAnnotations Pod annotations for cronjob pods {}
disasterRecovery.cronjob.resourcesPreset Set container resources according to one common preset (allowed values: none, nano, micro, small, medium, large, xlarge, 2xlarge). This is ignored if disasterRecovery.cronjob.resources is set (disasterRecovery.cronjob.resources is recommended for production). nano
disasterRecovery.cronjob.resources Set container requests and limits for different resources like CPU or memory (essential for production workloads) {}
disasterRecovery.cronjob.nodeSelector Node labels for cronjob pods assignment {}
disasterRecovery.cronjob.tolerations Tolerations for cronjob pods assignment []
disasterRecovery.cronjob.podLabels Labels that will be added to pods created by cronjob {}
disasterRecovery.cronjob.serviceAccountName Specifies the service account to use for disaster recovery cronjob ""
disasterRecovery.pvc.existingClaim A manually managed Persistent Volume and Claim ""
disasterRecovery.pvc.size PVC Storage Request 2Gi
disasterRecovery.pvc.storageClassName Storage Class for snapshots volume nfs
disasterRecovery.pvc.subPath Path within the volume from which to mount ""

Service account parameters

Name Description Value
serviceAccount.create Enable/disable service account creation true
serviceAccount.name Name of the service account to create or use ""
serviceAccount.automountServiceAccountToken Enable/disable auto mounting of service account token false
serviceAccount.annotations Additional annotations to be included on the service account {}
serviceAccount.labels Additional labels to be included on the service account {}

Other parameters

Name Description Value
pdb.create Enable/disable a Pod Disruption Budget creation true
pdb.minAvailable Minimum number/percentage of pods that should remain scheduled 51%
pdb.maxUnavailable Maximum number/percentage of pods that may be made unavailable ""

Specify each parameter using the --set key=value[,key=value] argument to helm install. For example,

helm install my-release \
  --set auth.rbac.rootPassword=secretpassword oci://REGISTRY_NAME/REPOSITORY_NAME/etcd

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

The above command sets the etcd root account password to secretpassword.

NOTE: Once this chart is deployed, it is not possible to change the application’s access credentials, such as usernames or passwords, using Helm. To change these application credentials after deployment, delete any persistent volumes (PVs) used by the chart and re-deploy it, or use the application’s built-in administrative tools if available.

Alternatively, a YAML file that specifies the values for the parameters can be provided while installing the chart. For example,

helm install my-release -f values.yaml oci://REGISTRY_NAME/REPOSITORY_NAME/etcd

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts. Tip: You can use the default values.yaml

Troubleshooting

Find more information about how to deal with common errors related to Bitnami’s Helm charts in this troubleshooting guide.

Upgrading

To 10.0.0

This major bump changes the following security defaults:

  • runAsGroup is changed from 0 to 1001
  • readOnlyRootFilesystem is set to true
  • resourcesPreset is changed from none to the minimum size working in our test suites (NOTE: resourcesPreset is not meant for production usage, but resources adapted to your use case).
  • global.compatibility.openshift.adaptSecurityContext is changed from disabled to auto.

This could potentially break any customization or init scripts used in your deployment. If this is the case, change the default values to the previous ones.

To 9.0.0

This version adds a new label app.kubernetes.io/component=etcd to the StatefulSet and pods. Due to this change, the StatefulSet will be replaced (as it’s not possible to add additional spec.selector.matchLabels to an existing StatefulSet) and the pods will be recreated. To upgrade to this version from a previous version, you need to run the following steps:

  1. Add new label to your pods

    kubectl label pod my-release-0 app.kubernetes.io/component=etcd
    # Repeat for all etcd pods, based on configured .replicaCount (excluding the etcd snappshoter pod, if .disasterRecovery.enabled is set to true)
    
  2. Remove the StatefulSet keeping the pods:

    kubectl delete statefulset my-release --cascade=orphan
    
  3. Upgrade your cluster:

    helm upgrade my-release oci://REGISTRY_NAME/REPOSITORY_NAME/etcd --set auth.rbac.rootPassword=$ETCD_ROOT_PASSWORD
    

    Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

To 8.0.0

This version reverts the change in the previous major bump (7.0.0). Now the default etcd branch is 3.5 again once confirmed by the etcd developers that this version is production-ready once solved the data corruption issue.

To 7.0.0

This version changes the default etcd branch to 3.4 as suggested by etcd developers. In order to migrate the data follow the official etcd instructions.

To 6.0.0

This version introduces several features and performance improvements:

  • The statefulset can now be scaled using kubectl scale command. Using helm upgrade to recalculate available endpoints is no longer needed.
  • The scripts used for bootstrapping, runtime reconfiguration, and disaster recovery have been refactored and moved to the etcd container with two purposes: removing technical debt & improving the stability.
  • Several parameters were reorganized to simplify the structure and follow the same standard used on other Bitnami charts:
    • etcd.initialClusterState is renamed to initialClusterState.
    • statefulset.replicaCount is renamed to replicaCount.
    • statefulset.podManagementPolicy is renamed to podManagementPolicy.
    • statefulset.updateStrategy and statefulset.rollingUpdatePartition are merged into updateStrategy.
    • securityContext.* is deprecated in favor of podSecurityContext and containerSecurityContext.
    • configFileConfigMap is deprecated in favor of configuration and existingConfigmap.
    • envVarsConfigMap is deprecated in favor of extraEnvVars, extraEnvVarsCM and extraEnvVarsSecret.
    • allowNoneAuthentication is renamed to auth.rbac.allowNoneAuthentication.
  • New parameters/features were added:
    • extraDeploy to deploy any extra desired object.
    • initContainers and sidecars to define custom init containers and sidecars.
    • extraVolumes, extraVolumeMounts and extraVolumeClaimTemplates to define custom volumes, mount points and volume claim templates.
    • Probes can be now customized, and support to startup probes is added.
    • LifecycleHooks can be customized using lifecycleHooks parameter.
    • The default command/args can be customized using command and args parameters.
  • Metrics integration with Prometheus Operator does no longer use a ServiceMonitor object, but a PodMonitor instead.

Consequences:

  • Backwards compatibility is not guaranteed unless you adapt you values.yaml according to the changes described above.

To 5.2.0

This version introduces bitnami/common, a library chart as a dependency. More documentation about this new utility could be found here. Please, make sure that you have updated the chart dependencies before executing any upgrade.

To 5.0.0

On November 13, 2020, Helm v2 support formally ended. This major version is the result of the required changes applied to the Helm Chart to be able to incorporate the different features added in Helm v3 and to be consistent with the Helm project itself regarding the Helm v2 EOL.

To 4.4.14

In this release we addressed a vulnerability that showed the ETCD_ROOT_PASSWORD environment variable in the application logs. Users are advised to update immediately. More information in this issue.

To 3.0.0

Backwards compatibility is not guaranteed. The following notables changes were included:

  • etcdctl uses v3 API.
  • Adds support for auto disaster recovery.
  • Labels are adapted to follow the Helm charts best practices.

To upgrade from previous charts versions, create a snapshot of the keyspace and restore it in a new etcd cluster. Only v3 API data can be restored. You can use the command below to upgrade your chart by starting a new cluster using an existing snapshot, available in an existing PVC, to initialize the members:

helm install new-release oci://REGISTRY_NAME/REPOSITORY_NAME/etcd \
  --set statefulset.replicaCount=3 \
  --set persistence.enabled=true \
  --set persistence.size=8Gi \
  --set startFromSnapshot.enabled=true \
  --set startFromSnapshot.existingClaim=my-claim \
  --set startFromSnapshot.snapshotFilename=my-snapshot.db

Note: You need to substitute the placeholders REGISTRY_NAME and REPOSITORY_NAME with a reference to your Helm chart registry and repository. For example, in the case of Bitnami, you need to use REGISTRY_NAME=registry-1.docker.io and REPOSITORY_NAME=bitnamicharts.

To 1.0.0

Backwards compatibility is not guaranteed unless you modify the labels used on the chart’s deployments. Use the workaround below to upgrade from versions previous to 1.0.0. The following example assumes that the release name is etcd:

kubectl delete statefulset etcd --cascade=false

License

Copyright © 2024 Broadcom. The term “Broadcom” refers to Broadcom Inc. and/or its subsidiaries.

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

check-circle-line exclamation-circle-line close-line
Scroll to top icon