charts/bitnami/consul

HashiCorp Consul Helm Chart

HashiCorp Consul has multiple components, but as a whole, it is a tool for discovering and configuring services in your infrastructure

TL;DR

$ helm repo add bitnami https://charts.bitnami.com/bitnami
$ helm install bitnami/consul

Introduction

This chart bootstraps a HashiCorp Consul 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. This Helm chart has been tested on top of Bitnami Kubernetes Production Runtime (BKPR). Deploy BKPR to get automated TLS certificates, logging and monitoring for your applications.

Prerequisites

• Kubernetes 1.12+
• Helm 2.11+ or Helm 3.0-beta3+
• PV provisioner support in the underlying infrastructure

Installing the Chart

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

$ helm repo add bitnami https://charts.bitnami.com/bitnami
$ helm install --name my-release bitnami/consul

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

Tip

: List all releases using helm list

Uninstalling the Chart

To uninstall/delete the my-release deployment:

$ helm delete my-release

The command removes all the Kubernetes components associated with the chart and deletes the release. Remove also the chart using --purge option:

$ helm delete --purge my-release

Parameters

The following tables lists the configurable parameters of the HashiCorp Consul chart and their default values.

Parameter	Description	Default
global.imageRegistry	Global Docker image registry	nil
global.imagePullSecrets	Global Docker registry secret names as an array	[] (does not add image pull secrets to deployed pods)
global.storageClass	Global storage class for dynamic provisioning	nil
image.registry	HashiCorp Consul image registry	docker.io
image.repository	HashiCorp Consul image name	bitnami/consul
image.tag	HashiCorp Consul image tag	{TAG_NAME}
image.pullPolicy	Image pull policy	IfNotPresent
image.pullSecrets	Specify docker-registry secret names as an array	[] (does not add image pull secrets to deployed pods)
nameOverride	String to partially override consul.fullname template with a string (will prepend the release name)	nil
fullnameOverride	String to fully override consul.fullname template with a string	nil
volumePermissions.enabled	Enable init container that changes volume permissions in the data directory (for cases where the default k8s runAsUser and fsUser values do not work)	false
volumePermissions.image.registry	Init container volume-permissions image registry	docker.io
volumePermissions.image.repository	Init container volume-permissions image name	bitnami/minideb
volumePermissions.image.tag	Init container volume-permissions image tag	stretch
volumePermissions.image.pullPolicy	Init container volume-permissions image pull policy	Always
volumePermissions.resources	Init container resource requests/limit	nil
replicas	Number of replicas	3
port	HashiCorp Consul http listening port	8500
service.rpcPort	HashiCorp Consul rpc listening port	8400
service.serflanPort	Container serf lan listening port	8301
service.serverPort	Container server listening port	8300
service.consulDnsPort	Container dns listening port	8600
service.uiPort	HashiCorp Consul UI port	80
datacenterName	HashiCorp Consul datacenter name	dc1
gossipKey	Gossip key for all members	nil
domain	HashiCorp Consul domain	consul
clientAddress	Address in which HashiCorp Consul will bind client interfaces	0.0.0.0
serflanAddress	Address used for Serf LAN communications	0.0.0.0
raftMultiplier	Multiplier used to scale key Raft timing parameters	10Gi
securityContext.enabled	Enable security context	true
securityContext.fsGroup	Group ID for the container	1001
securityContext.runAsUser	User ID for the container	1001
clusterDomain	Kubernetes cluster domain	cluster.local
updateStrategy.type	Statefulset update strategy policy	RollingUpdate
persistence.enabled	Use a PVC to persist data	true
persistence.storageClass	Storage class of backing PVC	nil (uses alpha storage class annotation)
persistence.accessMode	Use volume as ReadOnly or ReadWrite	ReadWriteOnce
persistence.size	Size of data volume	8Gi
persistence.annotations	Annotations for the persistent volume	nil
resources	Container resource requests and limits	{}
maxUnavailable	Pod disruption Budget maxUnavailable	1
nodeAffinity	HashiCorp Consul pod node-affinity setting	nil
antiAffinity	HashiCorp Consul pod anti-affinity setting	soft
ui.service.enabled	Use a service to access HashiCorp Consul Ui	true
ui.service.type	Kubernetes Service Type	ClusterIP
ui.service.annotations	Annotations for HashiCorp Consul UI service	{}
ui.service.loadBalancerIP	IP if HashiCorp Consul UI service type is LoadBalancer	nil
ingress.enabled	Enable ingress controller resource	false
ingress.certManager	Add annotations for cert-manager	false
ingress.annotations	Ingress annotations	[]
ingress.hosts[0].name	Hostname to your HashiCorp Consul installation	consul-ui.local
ingress.hosts[0].path	Path within the url structure	/
ingress.hosts[0].tls	Utilize TLS backend in ingress	false
ingress.hosts[0].tlsSecret	TLS Secret (certificates)	consul-ui.local-tls
ingress.secrets[0].name	TLS Secret Name	nil
ingress.secrets[0].certificate	TLS Secret Certificate	nil
ingress.secrets[0].key	TLS Secret Key	nil
configmap	HashiCorp Consul configuration to be injected as ConfigMap	nil
metrics.enabled	Start a side-car prometheus exporter	false
metrics.image	Exporter image	bitnami/consul-exporter
metrics.imageTag	Exporter image tag	{TAG_NAME}
metrics.imagePullPolicy	Exporter image pull policy	IfNotPresent
metrics.resources	Exporter resource requests/limit	{}
metrics.podAnnotations	Exporter annotations	{}
nodeSelector	Node labels for pod assignment	{}
livenessProbe.initialDelaySeconds	Delay before liveness probe is initiated	30
livenessProbe.periodSeconds	How often to perform the probe	10
livenessProbe.timeoutSeconds	When the probe times out	5
livenessProbe.successThreshold	Minimum consecutive successes for the probe to be considered successful after having failed.	1
livenessProbe.failureThreshold	Minimum consecutive failures for the probe to be considered failed after having succeeded.	6
podAnnotations	Pod annotations	{}
readinessProbe.initialDelaySeconds	Delay before readiness probe is initiated	5
readinessProbe.periodSeconds	How often to perform the probe	10
readinessProbe.timeoutSeconds	When the probe times out	5
readinessProbe.successThreshold	Minimum consecutive successes for the probe to be considered successful after having failed.	1
readinessProbe.failureThreshold	Minimum consecutive failures for the probe to be considered failed after having succeeded.	6

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

$ helm install --name my-release --set domain=consul-domain,gossipKey=secretkey bitnami/consul

The above command sets the HashiCorp Consul domain to consul-domain and sets the gossip key to secretkey.

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

$ helm install --name my-release -f values.yaml bitnami/consul

Tip

: You can use the default values.yaml

Configuration and installation details

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.

Production configuration

This chart includes a values-production.yaml file where you can find some parameters oriented to production configuration in comparison to the regular values.yaml. You can use this file instead of the default one.

• Start a side-car prometheus exporter:

- metrics.enabled: false
+ metrics.enabled: true

Ingress

This chart provides support for ingress resources. If you have an ingress controller installed on your cluster, such as nginx-ingress or traefik you can utilize the ingress controller to service your HashiCorp Consul UI application.

To enable ingress integration, please set ingress.enabled to true

Hosts

Most likely you will only want to have one hostname that maps to this HashiCorp Consul installation, however it is possible to have more than one host. To facilitate this, the ingress.hosts object is an array.

For each item, please indicate a name, tls, tlsSecret, and any annotations that you may want the ingress controller to know about.

Indicating TLS will cause HashiCorp Consul to generate HTTPS urls, and HashiCorp Consul will be connected to at port 443. The actual secret that tlsSecret references does not have to be generated by this chart. However, please note that if TLS is enabled, the ingress record will not work until this secret exists.

For annotations, please see this document. Not all annotations are supported by all ingress controllers, but this document does a good job of indicating which annotation is supported by many popular ingress controllers.

TLS Secrets

This chart will facilitate the creation of TLS secrets for use with the ingress controller, however this is not required. There are three common use cases:

• helm generates / manages certificate secrets
• user generates / manages certificates separately
• an additional tool (like kube-lego) manages the secrets for the application

In the first two cases, one will need a certificate and a key. We would expect them to look like this:

• certificate files should look like (and there can be more than one certificate if there is a certificate chain)

-----BEGIN CERTIFICATE-----
MIID6TCCAtGgAwIBAgIJAIaCwivkeB5EMA0GCSqGSIb3DQEBCwUAMFYxCzAJBgNV
...
jScrvkiBO65F46KioCL9h5tDvomdU1aqpI/CBzhvZn1c0ZTf87tGQR8NK7v7
-----END CERTIFICATE-----

• keys should look like:

-----BEGIN RSA PRIVATE KEY-----
MIIEogIBAAKCAQEAvLYcyu8f3skuRyUgeeNpeDvYBCDcgq+LsWap6zbX5f8oLqp4
...
wrj2wDbCDCFmfqnSJ+dKI3vFLlEz44sAV8jX/kd4Y6ZTQhlLbYc=
-----END RSA PRIVATE KEY-----

If you are going to use helm to manage the certificates, please copy these values into the certificate and key values for a given ingress.secrets entry.

Please see this example for more information.

Enable TLS encryption between servers

You must manually create a secret containing your PEM-encoded certificate authority, your PEM-encoded certificate, and your PEM-encoded private key.

Take into account that you will need to create a config map with the proper configuration.

If the secret is specified, the chart will locate those files at /opt/bitnami/consul/certs/, so you will want to use the below snippet to configure HashiCorp Consul TLS encryption in your config map:

  "ca_file": "/opt/bitnami/consul/certs/ca.pem",
  "cert_file": "/opt/bitnami/consul/certs/consul.pem",
  "key_file": "/opt/bitnami/consul/certs/consul-key.pem",
  "verify_incoming": true,
  "verify_outgoing": true,
  "verify_server_hostname": true,

After creating the secret, you can install the helm chart specyfing the secret name using tlsEncryptionSecretName=consul-tls-encryption.

Metrics

The chart can optionally start a metrics exporter endpoint on port 9107 for prometheus. The data exposed by the endpoint is intended to be consumed by a prometheus chart deployed within the cluster and as such the endpoint is not exposed outside the cluster.

Persistence

The Bitnami HashiCorp Consul image stores the HashiCorp Consul data at the /bitnami path of the container.

Persistent Volume Claims are used to keep the data across deployments. This is known to work in GCE, AWS, and minikube. See the Configuration section to configure the PVC or to disable persistence.

Adjust permissions of persistent volume mountpoint

As the image run as non-root by default, it is necessary to adjust the ownership of the persistent volume so that the container can write data into it.

By default, the chart is configured to use Kubernetes Security Context to automatically change the ownership of the volume. However this feature does not work in all Kubernetes distributions. As an alternative, this chart supports using an initContainer to change the ownership of the volume before mounting it in the final destination.

You can enable this initContainer by setting volumePermissions.enabled to true.

Upgrading

To 6.0.0

This release updates the Bitnami Consul container to 1.6.1-debian-9-r6, which is based on Bash instead of Node.js.

To 3.1.0

Consul container was moved to a non-root approach. There shouldn't be any issue when upgrading since the corresponding securityContext is enabled by default. Both the container image and the chart can be upgraded by running the command below:

$ helm upgrade my-release stable/consul

If you use a previous container image (previous to 1.4.0-r16) disable the securityContext by running the command below:

$ helm upgrade my-release stable/consul --set securityContext.enabled=fase,image.tag=XXX

To 2.0.0

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 2.0.0. The following example assumes that the release name is consul:

$ kubectl delete statefulset consul --cascade=false