Apache Tomcat, often referred to as Tomcat, is an open-source web server and servlet container developed by the Apache Software Foundation. Tomcat implements several Java EE specifications including Java Servlet, JavaServer Pages, Java EL, and WebSocket, and provides a "pure Java" HTTP web server environment for Java code to run in.
$ helm repo add bitnami https://charts.bitnami.com/bitnami
$ helm install my-release bitnami/tomcatThis chart bootstraps a Tomcat 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.
- Kubernetes 1.12+
- Helm 3.1.0
- PV provisioner support in the underlying infrastructure
- ReadWriteMany volumes for deployment scaling
To install the chart with the release name my-release:
$ helm repo add bitnami https://charts.bitnami.com/bitnami
$ helm install my-release bitnami/tomcatThese commands deploy Tomcat 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
To uninstall/delete the my-release deployment:
$ helm delete my-releaseThe command removes all the Kubernetes components associated with the chart and deletes the release.
The following tables lists the configurable parameters of the Tomcat chart and their default values per section/component:
| 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 |
| Parameter | Description | Default |
|---|---|---|
nameOverride |
String to partially override common.names.fullname | nil |
fullnameOverride |
String to fully override common.names.fullname | nil |
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 | [] (evaluated as a template) |
kubeVersion |
Force target Kubernetes version (using Helm capabilities if not set) | nil |
| Parameter | Description | Default |
|---|---|---|
image.registry |
Tomcat image registry | docker.io |
image.repository |
Tomcat image name | bitnami/tomcat |
image.tag |
Tomcat image tag | {TAG_NAME} |
image.pullPolicy |
Tomcat image pull policy | IfNotPresent |
image.pullSecrets |
Specify docker-registry secret names as an array | [] (does not add image pull secrets to deployed pods) |
image.debug |
Specify if debug logs should be enabled | false |
hostAliases |
Add deployment host aliases | [] |
tomcatUsername |
Tomcat admin user | user |
tomcatPassword |
Tomcat admin password | random 10 character alphanumeric string |
tomcatAllowRemoteManagement |
Enable remote access to management interface | 0 (disabled) |
command |
Override default container command (useful when using custom images) | nil |
args |
Override default container args (useful when using custom images) | nil |
extraEnvVars |
Extra environment variables to be set on Tomcat container | {} |
extraEnvVarsCM |
Name of existing ConfigMap containing extra env vars | nil |
extraEnvVarsSecret |
Name of existing Secret containing extra env vars | nil |
| Parameter | Description | Default |
|---|---|---|
deployment.type |
Use Deployment or StatefulSet | deployment |
replicaCount |
Specify number of Tomcat replicas | 1 |
containerPort |
HTTP port to expose at container level | 8080 |
containerExtraPorts |
Extra ports to expose at container level | {} |
podSecurityContext |
Tomcat pods' Security Context | Check values.yaml file |
containerSecurityContext |
Tomcat containers' Security Context | Check values.yaml file |
resources.limits |
The resources limits for the Tomcat container | {} |
resources.requests |
The requested resources for the Tomcat container | {"memory": "512Mi", "cpu": "300m"} |
livenessProbe |
Liveness probe configuration for Tomcat | Check values.yaml file |
readinessProbe |
Readiness probe configuration for Tomcat | Check values.yaml file |
customLivenessProbe |
Override default liveness probe | nil |
customReadinessProbe |
Override default readiness probe | nil |
updateStrategy |
Strategy to use to update Pods | Check values.yaml file |
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 | {} (evaluated as a template) |
nodeSelector |
Node labels for pod assignment | {} (evaluated as a template) |
tolerations |
Tolerations for pod assignment | [] (evaluated as a template) |
podLabels |
Extra labels for Tomcat pods | {} (evaluated as a template) |
podAnnotations |
Annotations for Tomcat pods | {} (evaluated as a template) |
extraVolumeMounts |
Optionally specify extra list of additional volumeMounts for Tomcat container(s) | [] |
extraVolumes |
Optionally specify extra list of additional volumes for Tomcat pods in Deployment | [] |
extraVolumeClaimTemplates |
Optionally specify extra list of additional volume claim templates for Tomcat pods in StatefulSet | [] |
initContainers |
Add additional init containers to the Tomcat pods | {} (evaluated as a template) |
sidecars |
Add additional sidecar containers to the Tomcat pods | {} (evaluated as a template) |
persistence.enabled |
Enable persistence | true |
persistence.storageClass |
PVC Storage Class for Tomcat volume | nil (uses alpha storage class annotation) |
persistence.existingClaim |
An Existing PVC name for Tomcat volume | nil (uses alpha storage class annotation) |
persistence.accessModes |
PVC Access Modes for Tomcat volume | ReadWriteOnce |
persistence.size |
PVC Storage Request for Tomcat volume | 8Gi |
persistence.selectorLabels |
Selector labels to use in volume claim template for Tomcat volume (Applicable when deployment.type is statefulset) | nil |
| Parameter | Description | Default |
|---|---|---|
service.type |
Kubernetes Service type | LoadBalancer |
service.port |
Service HTTP port | 80 |
service.nodePort |
Kubernetes http node port | "" |
service.loadBalancerIP |
Kubernetes LoadBalancerIP to request | nil |
service.externalTrafficPolicy |
Enable client source IP preservation | Cluster |
service.annotations |
Annotations for Tomcat service | {} (evaluated as a template) |
ingress.enabled |
Enable ingress controller resource | false |
ingress.apiVersion |
Force Ingress API version (automatically detected if not set) | `` |
ingress.path |
Ingress path | / |
ingress.pathType |
Ingress path type | ImplementationSpecific |
ingress.certManager |
Add annotations for cert-manager | false |
ingress.hostname |
Default host for the ingress resource | tomcat.local |
ingress.tls |
Enable TLS configuration for the hostname defined at ingress.hostname parameter |
false |
ingress.annotations |
Ingress annotations | {} (evaluated as a template) |
ingress.extraHosts[0].name |
Additional hostnames to be covered | nil |
ingress.extraHosts[0].path |
Additional hostnames to be covered | nil |
ingress.extraTls[0].hosts[0] |
TLS configuration for additional hostnames to be covered | nil |
ingress.extraTls[0].secretName |
TLS configuration for additional hostnames to be covered | nil |
ingress.secrets[0].name |
TLS Secret Name | nil |
ingress.secrets[0].certificate |
TLS Secret Certificate | nil |
ingress.secrets[0].key |
TLS Secret Key | nil |
| Parameter | Description | Default |
|---|---|---|
volumePermissions.enabled |
Enable init container that changes volume permissions in the data directory | false |
volumePermissions.image.registry |
Init container volume-permissions image registry | docker.io |
volumePermissions.image.repository |
Init container volume-permissions image name | bitnami/bitnami-shell |
volumePermissions.image.tag |
Init container volume-permissions image tag | "10" |
volumePermissions.image.pullPolicy |
Init container volume-permissions image pull policy | Always |
volumePermissions.image.pullSecrets |
Specify docker-registry secret names as an array | [] (does not add image pull secrets to deployed pods) |
volumePermissions.resources.limits |
Init container volume-permissions resource limits | {} |
volumePermissions.resources.requests |
Init container volume-permissions resource requests | {} |
The above parameters map to the env variables defined in bitnami/tomcat. For more information please refer to the bitnami/tomcat image documentation.
Specify each parameter using the --set key=value[,key=value] argument to helm install. For example,
$ helm install my-release \
--set tomcatUser=manager,tomcatPassword=password bitnami/tomcatThe above command sets the Tomcat management username and password to manager and password respectively.
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 bitnami/tomcatTip: You can use the default values.yaml
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.
To modify the Tomcat version used in this chart you can specify a valid image tag using the image.tag parameter. For example, image.tag=X.Y.Z. This approach is also applicable to other images like exporters.
The Bitnami Tomcat image stores the Tomcat data and configurations at the /bitnami/tomcat 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 Parameters section to configure the PVC or to disable persistence.
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.
In case you want to add extra environment variables (useful for advanced operations like custom init scripts), you can use the extraEnvVars property.
extraEnvVars:
- name: LOG_LEVEL
value: DEBUGAlternatively, you can use a ConfigMap or a Secret with the environment variables. To do so, use the extraEnvVarsCM or the extraEnvVarsSecret values.
If you have a need for additional containers to run within the same pod as the Tomcat 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: 1234Similarly, you can add extra init containers using the initContainers parameter.
initContainers:
- name: your-image-name
image: your-image
imagePullPolicy: Always
ports:
- name: portname
containerPort: 1234This 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.
Find more information about how to deal with common errors related to Bitnami’s Helm charts in this troubleshooting guide.
- Chart labels were adapted to follow the Helm charts standard labels.
- Ingress configuration was also adapted to follow the Helm charts best practices.
- This version also 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.
Consequences:
- Backwards compatibility is not guaranteed. However, you can easily workaround this issue by removing Tomcat deployment before upgrading (the following example assumes that the release name is
tomcat):
$ export TOMCAT_PASSWORD=$(kubectl get secret --namespace default tomcat -o jsonpath="{.data.tomcat-password}" | base64 --decode)
$ kubectl delete deployments.apps tomcat
$ helm upgrade tomcat bitnami/tomcat --set tomcatPassword=$TOMCAT_PASSWORDOn November 13, 2020, Helm v2 support was formally finished, 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.
- Previous versions of this Helm Chart use
apiVersion: v1(installable by both Helm 2 and 3), this Helm Chart was updated toapiVersion: v2(installable by Helm 3 only). Here you can find more information about theapiVersionfield. - The different fields present in the Chart.yaml file has been ordered alphabetically in a homogeneous way for all the Bitnami Helm Charts
- If you want to upgrade to this version from a previous one installed with Helm v3, you shouldn't face any issues
- If you want to upgrade to this version using Helm v2, this scenario is not supported as this version doesn't support Helm v2 anymore
- If you installed the previous version with Helm v2 and wants to upgrade to this version with Helm v3, please refer to the official Helm documentation about migrating from Helm v2 to v3
- https://docs.bitnami.com/tutorials/resolve-helm2-helm3-post-migration-issues/
- https://helm.sh/docs/topics/v2_v3_migration/
- https://helm.sh/blog/migrate-from-helm-v2-to-helm-v3/
This release updates the Bitnami Tomcat container to 9.0.26-debian-9-r0, which is based on Bash instead of Node.js.
Tomcat 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 bitnami/tomcat
If you use a previous container image (previous to 8.5.35-r26) disable the securityContext by running the command below:
$ helm upgrade my-release bitnami/tomcat --set securityContext.enabled=false,image.tag=XXX
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 tomcat:
$ kubectl patch deployment tomcat --type=json -p='[{"op": "remove", "path": "/spec/selector/matchLabels/chart"}]'