As Appian on Kubernetes is only supported for non-production environments, there is no supported path for upgrading from 21.4 to 22.1 or higher. For environments where future upgrades are desired, use Appian 22.1.
This page walks through how to install Appian on Kubernetes for self managed customers. The instructions show how to install on either a server-based cluster or locally for testing. It is aimed at platform engineers with some experience with Kubernetes, Helm, and Docker images; although this experience is not required, it will make life much easier.
Appian is installed on Kubernetes using a Custom Resource Definition (CRD) and an Operator. Before performing the install you should be familiar with these concepts. To read about them, see What is the Appian Operator?
Make sure you have the following prerequisites and system requirements before installing Appian on Kubernetes.
You’ll need to request license files specifically for Appian on Kubernetes. There are two types of licenses: temporary and long-term.
Generating the long-term license files can take up to 4-5 business days. You'll want to request temporary license files first, or both the temporary and long-term licenses in the same request.
You can request temporary and long-term licenses by doing the following.
appian-k8s-appn. If you’re currently using a temporary license on an install and want to upgrade it to a long-term license, you'll want this to be the same name you designated in the .metadata.name field of your Appian CR to make it easier to upgrade. This way you can simply update the Kubernetes secrets with the long-term license files, and avoid having to additionally stop your Appian site, change the name, and restart.You’ll need to download the Appian on Kubernetes images and operator by doing the following.
We’ll use these artifacts later during the install.
Your environment should have the recommended hardware requirements for running Appian.
Docker is required for the container-based install. See Docker’s Getting Started to install. If you are installing Appian locally to test it, you’ll want to install Docker Desktop.
Kubernetes v1.16 or later is required for the Appian install. This version made custom resources available, and is required to run the Appian custom resource definition.
To check your server version, in a command terminal run kubectl version --short.
For testing the install of Appian on Kubernetes locally, Docker Desktop includes a Kubernetes environment it can be installed on. You can set things up as follows.
Check what the current context is.
kubectl config current-context
If the result of the previous command is not docker-desktop, run the following command to set the context.
kubectl config set-context docker-desktop
Helm v3 or later is required to install the Appian Operator, and should be available where Appian is deployed. See Installing Helm.
Appian needs to be exposed outside of Kubernetes to allow access to Apache Web Server (httpd) and webapp components. See Exposing Appian Outside Kubernetes to learn about different ways of exposing Appian.
How you choose to expose Appian will affect the configuration of the Appian custom resource; we’ll remind you of this configuration during that step.
To expose Appian via Ingress and enable testing the Appian install locally, you can optionally do a new install of NGINX Ingress Controller on Kubernetes. If you are exposing Appian using a different method or are already using an ingress controller on your Kubernetes cluster, you can ignore this step.
Appian on Kubernetes does not install a relational database. You’ll need to bring your own relational database for each site to serve as its Appian/primary data source. You’ll also want to provide at least one business data source to use data stores.
Your database may be either running on the Kubernetes cluster or running outside the cluster. In these install instructions, we'll show how to make a connection to MariaDB running on the cluster. If you want to use a direct connection to a database outside the cluster, you can add database details similar to our MariaDB example, but you'll need to make sure that the database is accessible from within the cluster.
If you are going to run Appian with either MySQL or IBM Db2, or use older drivers for one of the other supported DBs (MariaDB, Oracle, or Microsoft SQL Server, or PostgreSQL) see the section on setting up RDBMS/JDBC drivers.
To enable testing the Appian install locally, you can optionally do a new install of MariaDB on Kubernetes and use it as the primary data source in our Appian site. We’ll reference this new MariaDB instance in our Appian CR configuration during the install steps.
If you already have an RDBMS, you can ignore this step and configure the Appian CR using the details described in the install steps.
Create a new namespace in Kubernetes for our Appian site. We’ll use this namespace to house MariaDB and the Appian site. The namespace can have any name, though the rest of our instructions will use my-appian-site.
kubectl create ns my-appian-site
Install MariaDB using Helm on the namespace with the following commands.
helm repo add bitnami https://charts.bitnami.com/bitnami
helm install mariadb-appian --namespace my-appian-site --set auth.database=appian-k8s-appn,auth.username=appian-k8s-appn,auth.password=appian-k8s-appn bitnami/mariadb
In the install command, we are creating a database with auth.database and setting up an initial username and password with auth.username and auth.password. We’ll use these later in the Appian CR configuration.
The output of the install should be similar to the following.
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NAME: mariadb-appian
LAST DEPLOYED: Tue Aug 10 15:23:33 2021
NAMESPACE: my-appian-site
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
** Please be patient while the chart is being deployed **
Tip:
Watch the deployment status using the command: kubectl get pods -w --namespace my-appian-site -l app.kubernetes.io/instance=mariadb-appian
Services:
echo Primary: mariadb-appian.my-appian-site.svc.cluster.local:3306
Administrator credentials:
Username: root
Password : $(kubectl get secret --namespace my-appian-site mariadb-appian -o jsonpath="{.data.mariadb-root-password}" | base64 --decode)
To connect to your database:
1. Run a pod that you can use as a client:
kubectl run mariadb-appian-client --rm --tty -i --restart='Never' --image docker.io/bitnami/mariadb:10.5.12-debian-10-r0 --namespace my-appian-site --command -- bash
2. To connect to primary service (read/write):
mysql -h mariadb-appian.my-appian-site.svc.cluster.local -uroot -p appian-k8s-appn
To upgrade this helm chart:
1. Obtain the password as described on the 'Administrator credentials' section and set the 'auth.rootPassword' parameter as shown below:
ROOT_PASSWORD=$(kubectl get secret --namespace my-appian-site mariadb-appian -o jsonpath="{.data.mariadb-root-password}" | base64 --decode)
helm upgrade --namespace my-appian-site mariadb-appian bitnami/mariadb --set auth.rootPassword=$ROOT_PASSWORD
From this output, copy the Services URL similar to what's highlighted below.
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Services:
echo Primary: `mariadb-appian.my-appian-site.svc.cluster.local:3306`
Later we’ll use this URL in the Appian CR to connect to our database.
Use the following command to check on the progress of the MariaDB install.
kubectl get pods -w --namespace my-appian-site -l app.kubernetes.io/instance=mariadb-appian
When it has completed, the READY column will have 1/1 pods and STATUS will be Running. This may take several minutes to complete.
If you have any trouble with the install, see Bitnami’s Helm chart troubleshooting guide.
Once all your prerequisites are in order, the following steps will install Appian on Kubernetes.
If you haven’t done so already, create a new namespace in Kubernetes for your Appian site and all its components. The namespace can have any name, though the rest of our instructions will use my-appian-site.
kubectl create ns my-appian-site
Do the following steps to install cert-manager, which is used to validate the Appian CR configuration. For more on how cert-manager is used, continue reading below.
By default, the Appian operator creates webhooks to perform validation on the Appian custom resource (mutating and validating admission webhooks). This ensures the CR is initially set up correctly and validated on each update. The webhooks require certificates, and the Appian Operator Helm chart depends on cert-manager to provision certificates for the webhook servers.
The Appian operator Helm chart doesn’t currently support other certificate solutions. If you cannot deploy cert-manager in your environment or would like to disable the webhooks, set webhooks.enabled to false when installing the operator chart.
Having downloaded your images and licenses as TAR files, we’ll now load these onto Kubernetes.
Load the operator image and Appian images (all TAR.GZ files) into Docker with docker load -i <IMAGE>:
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docker load -i appian-operator-<APPIAN_OPERATOR_VERSION>.tar.gz
docker load -i zookeeper-<APPIAN_VERSION>.tar.gz
docker load -i kafka-<APPIAN_VERSION>.tar.gz
docker load -i search-server-<APPIAN_VERSION>.tar.gz
docker load -i data-server-<APPIAN_VERSION>.tar.gz
docker load -i service-manager-<APPIAN_VERSION>.tar.gz
docker load -i webapp-<APPIAN_VERSION>.tar.gz
docker load -i httpd-<APPIAN_VERSION>.tar.gz
Afterwards, verify that the images were loaded correctly with the following command.
docker images registry.example.com/appian/*
The output should show all the images you’ve just loaded, similar to the following.
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REPOSITORY TAG IMAGE ID CREATED SIZE
registry.example.com/appian/appian-operator v0.65.0 06d27ba22776 2 months ago 48.7MB
registry.example.com/appian/webapp 21.2.360.0 17bdc49b8890 2 months ago 1.28GB
registry.example.com/appian/service-manager 21.2.360.0 58ee3df15880 2 months ago 667MB
registry.example.com/appian/httpd 21.2.360.0 7757cdfb8036 2 months ago 704MB
registry.example.com/appian/search-server 0.213.1 3a51063f0112 2 months ago 455MB
registry.example.com/appian/data-server 0.215.2 c434d4ba1c3d 3 months ago 744MB
registry.example.com/appian/kafka 2.13-2.7.0-appian-4-prod-8d0de3b2 49257fb571bb 4 months ago 997MB
registry.example.com/appian/zookeeper 3.7.0-prod-939f6a88 7dce817715d4 5 months ago 819MB
Each Docker image has an initial registry hostname of registry.example.com. If you have your own docker registry and are not running this locally for testing, each image will need to be retagged with your specific Docker registry.
For example, if your registry URL is my.registry.com, you would tag each image similar to:
docker tag registry.example.com/appian/webapp:20.4.420.0 my.registry.com/appian/webapp:20.4.420.0
docker tag registry.example.com/appian/data-server:0.215.2 my.registry.com/appian/data-server:0.215.2
docker tag ...
Your commands, including the tags on the end, may differ from the commands above.
If you retagged images for your registry in the last step, you’ll then need to push each image to your specific registry.
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docker push my.registry.com/appian/appian-operator:<APPIAN_OPERATOR_VERSION>
docker push my.registry.com/appian/zookeeper:<ZOOKEEPER_TAG>
docker push my.registry.com/appian/kafka:<KAFKA_TAG>
docker push my.registry.com/appian/search-server:<ZOOKEEPER_TAG>
docker push my.registry.com/appian/data-server:<DATA_SERVER_TAG>
docker push my.registry.com/appian/service-manager:<APPIAN_VERSION>
docker push my.registry.com/appian/webapp:<APPIAN_VERSION>
docker push my.registry.com/appian/httpd:<APPIAN_VERSION>
Having requested your licenses, you’ll have received a zip with two files: k3.lic and k4.lic. We’ll install these as secrets on Kubernetes.
Load the product license files as secrets into Kubernetes.
kubectl -n my-appian-site create secret generic k3lic --from-file=<PATH TO LICENSE>/k3.lic
kubectl -n my-appian-site create secret generic k4lic --from-file=<PATH TO LICENSE>/k4.lic
The following steps will create the Appian operator from the downloaded TGZ file Helm chart.
If you already have your own Helm chart repository, you could optionally load the Appian operator Helm chart into your repository and run it from there. Be sure you add the repository to your Helm client via helm repo add. The install command below would then reference the helm chart in the repository rather than the TGZ file.
Create a new namespace for the Appian operator. The namespace can have any name, though the rest of our instructions will use appian-operator.
kubectl create ns appian-operator
Install the Appian operator Helm chart TGZ file that was previously downloaded.
helm install appian-operator <PATH TO OPERATOR HELM CHART .TGZ FILE> --wait --namespace appian-operator --set image.repository=<DOCKER IMAGE REPOSITORY>/appian/appian-operator
For example:
helm install appian-operator appian-operator-v0.65.0.tgz --wait --namespace appian-operator --set image.repository=registry.example.com/appian/appian-operator
If the Docker registry where your Appian operator image resides is private, follow the instructions here to create a Secret of type docker-registry and provide the name of the Secret via the option --set imagePullSecrets={<NAME>} in the command above.
If you’ve pushed the operator image with a different tag that doesn’t match the version / app version of the chart, you’ll want to include the option --set image.tag=<TAG>.
This command may take a minute or two to complete. When complete, check that the correct Appian operator Deployments, ReplicaSets, and Pods were created.
kubectl -n appian-operator get deployments,replicasets,pods
The output should be similar to:
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NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/appian-operator-controllers 1/1 1 1 90s
deployment.apps/appian-operator-webhooks 1/1 1 1 90s
NAME DESIRED CURRENT READY AGE
replicaset.apps/appian-operator-controllers-55cfcf74f 1 1 1 90s
replicaset.apps/appian-operator-webhooks-5bd6588b95 1 1 1 90s
NAME READY STATUS RESTARTS AGE
pod/appian-operator-controllers-55cfcf74f-sr4jd 1/1 Running 0 90s
pod/appian-operator-webhooks-5bd6588b95-7lggk 1/1 Running 0 90s
For each of the operator’s controllers and webhooks, you should see a single Deployment, ReplicaSet, and Pod. Once the Pods’ STATUS are all Running, the READY column should show 1/1 within 1 minute.
Please note that the usage of appians below, and elsewhere, refers to multiple instances of Appian in a cluster. This pluralization follows
Kubernetes conventions on resource naming.
Validate that the Appian CRD installed successfully by running:
kubectl get crd appians.crd.k8s.appian.com
The output should be similar to:
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NAME CREATED AT
appians.crd.k8s.appian.com 2021-07-21T17:37:31Z
If you have any trouble installing the operator, see Troubleshooting Appian on Kubernetes.
We’ll now configure a YAML file used as the spec to deploy the Appian CR.
Download the appian.yaml file (it can also be copied from the code block below). This will serve as a template for the Appian CR spec.
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apiVersion: crd.k8s.appian.com/v1alpha1
kind: Appian
metadata:
# Temporary licenses: name can be any lower case name, one word
# Long-term licenses: name must match the requested Appian site name for the license
name: appian-k8s-appn
spec:
webapp:
image:
repository: registry.example.com/appian/webapp
tag: 21.2.360.0
replicas: 1
resources:
requests:
cpu: 1000m
memory: 4Gi
limits:
cpu: 2000m
memory: 8Gi
volumeClaimTemplateSpec:
accessModes:
- "ReadWriteOnce"
resources:
requests:
storage: "5Gi"
# The scheme, host, and, optionally, port of the site
# See Post-Install_Configurations.html#configure-your-site-url
url: http://myappiansite.com
# The scheme, host, and, optionally, port of the site's static and dynamic content URLs
# See Post-Install_Configurations.html#configure-your-static-and-dynamic-content-urls
# staticUrl: http://myappiansite-static.com
# dynamicUrl: http://myappiansite-dynamic.com
dataSources:
# Connection information for the relational database to use as the
# Appian/primary data source. If connecting to MySQL or IBM Db2, use an
# init container to add the appropriate RDBMS/JDBC driver JAR to Tomcat's classpath
# See Configuring_Relational_Databases.html#provide-data-source-connection-information
primary:
name: jdbc/AppianPrimaryDS
driverClassName: org.mariadb.jdbc.Driver
url: "jdbc:mariadb://mariadb-appian.my-appian-site.svc.cluster.local:3306/appian-k8s-appn?useOldAliasMetadataBehavior=true"
username: appian-k8s-appn
password: appian-k8s-appn
validationQuery: "SELECT 1"
# Key-value pairs to inject into the custom.properties file shared by all components
# See Custom_Configurations.md#custom-properties
customProperties: {}
# my.custom.key: my-custom-value
zookeeper:
image:
repository: registry.example.com/appian/zookeeper
tag: 3.7.0-prod-939f6a88
replicas: 1
resources:
requests:
cpu: 250m
memory: 1Gi
limits:
cpu: 500m
memory: 2Gi
volumeClaimTemplateSpec:
accessModes:
- "ReadWriteOnce"
resources:
requests:
storage: "5Gi"
kafka:
image:
repository: registry.example.com/appian/kafka
tag: 2.13-2.7.0-appian-4-prod-8d0de3b2
replicas: 1
resources:
requests:
cpu: 250m
memory: 1Gi
limits:
cpu: 500m
memory: 2Gi
volumeClaimTemplateSpec:
accessModes:
- "ReadWriteOnce"
resources:
requests:
storage: "5Gi"
searchServer:
image:
repository: registry.example.com/appian/search-server
tag: 0.213.1
replicas: 1
resources:
requests:
cpu: 500m
memory: 1.25Gi
limits:
cpu: 1000m
memory: 1.25Gi
volumeClaimTemplateSpec:
accessModes:
- "ReadWriteOnce"
resources:
requests:
storage: "5Gi"
dataServer:
image:
repository: registry.example.com/appian/data-server
tag: 0.215.2
replicas: 1
resources:
requests:
cpu: 500m
memory: 2Gi
limits:
cpu: 1000m
memory: 4Gi
volumeClaimTemplateSpec:
accessModes:
- "ReadWriteOnce"
resources:
requests:
storage: "5Gi"
serviceManager:
image:
repository: registry.example.com/appian/service-manager
tag: 21.2.360.0
replicas: 1
resources:
requests:
cpu: 1000m
memory: 4Gi
limits:
cpu: 2000m
memory: 8Gi
volumeClaimTemplateSpec:
accessModes:
- "ReadWriteOnce"
resources:
requests:
storage: "5Gi"
httpd:
image:
repository: registry.example.com/appian/httpd
tag: 21.2.360.0
replicas: 1
ingress:
enabled: true
At minimum, change the following field values in appian.yaml with custom values. Save the file.
| Key | Current Value | Your Value |
|---|---|---|
metadata.name |
appian-k8s-appn |
This should be the same Appian site name specified when requesting your long-term license. If you are using a temporary license, you can specify any name here, lower-case, all one word. If you intend to upgrade the temporary license on an install to a long-term license, it is easiest to keep this same name for the long-term license request. |
spec.webapp.url |
http://myappiansite.com |
Fully qualified domain name of the Appian site's URL including the scheme, host, and, optionally, port. For example: http://www.example.com:8080. For more info, see SERVER_AND_PORT in Configure your Site URL. If you are running this locally to test it, you can run the terminal command hostname to determine a valid URL for your machine. The URL would then be set as: http://<HOSTNAME COMMAND URL> |
spec.webapp.dataSources.primary.driverClassName |
org.mariadb.jdbc.Driver |
Driver class name for your RDBMS. For examples of each of the supported databases, see Configuring Data Sources. |
spec.webapp.dataSources.primary.url |
jdbc:mariadb://mariadb-appian.my-appian-site.svc.cluster.local:3306/appian-k8s-appn?useOldAliasMetadataBehavior=true |
Primary data source connection URL of your RDBMS. For URL examples of each of the supported databases, see Configuring Data Sources. If you installed a new copy of MariaDB in earlier steps, use the Service URL copied from the install step, along with the database that was created: jdbc:mariadb://<MARIADB SERVICE URL>/<MARIADB DATABASE>?useOldAliasMetadataBehavior=trueFor example: jdbc:mariadb://mariadb-appian.my-appian-site.svc.cluster.local:3306/appian-k8s-appn?useOldAliasMetadataBehavior=true |
spec.webapp.dataSources.primary.username |
appian-k8s-appn |
Plain-text username for your RDBMS connection. If you installed a new copy of MariaDB in earlier steps, this will be the username created in that step. For example: appian-k8s-appn. |
spec.webapp.dataSources.primary.password |
appian-k8s-appn |
Plain-text password for your RDBMS connection. If you installed a new copy of MariaDB in earlier steps, this will be the password created in that step. For example: appian-k8s-appn. |
spec.webapp.dataSources.primary.validationQuery |
"SELECT 1" |
Validation query for your RDBMS connection. For examples of each of the supported databases, see Configuring Data Sources. If you installed a new copy of MariaDB in earlier steps, this will be "SELECT 1". |
spec.<COMPONENT>.image.repository(Multiple fields - one field per component) |
registry.example.com/appian/<COMPONENT> |
Image location on your Docker registry of each Appian component. If you are using a custom registry, change this image for each Appian component. If you did not re-tag your images and push to a custom registry, use the current values that include registry.example.com. |
spec.<COMPONENT>.image.tag(Multiple fields - one field per component) |
Various tag values for each Appian component. | The image version number for each Appian component. You can find these tags with the command: docker images <MY DOCKER REGISTRY>/appian/*For example: docker images registry.example.com/appian/* |
Be sure to change any other custom values in appian.yaml spec. For a detailed reference of all allowable fields, refer to the custom resource definitions API documentation.
Here are some configuration settings to consider.
.spec.ingress.enabled to true in the spec. If you want to configure Appian to be exposed in other ways, see Exposing Appian Outside Kubernetes for the different configuration options.spec.<COMPONENT>.resources fields in the appian.yaml spec are suggested resource values based on each component. See Managing Resources in Containers for the meaning and syntax of these fields.spec.<COMPONENT>.volumeClaimTemplateSpec fields have suggested values that define this storage. For more on these fields, see PersistentVolumeClaimSpec.appian.yaml specifies one Pod replica per Appian component. You may consider specifying more replicas for components such as Webapp or Apache Web Server (http).You will need to set the Search Server kernel settings either using an init container in the CR spec or using admin commands after the install.
Run kubectl create to create the Appian site based on the appian.yaml:
kubectl create -n my-appian-site -f <PATH TO APPIAN.YAML>
It will take about 20-30 minutes for the Appian site to fully start. Check progress on the various Appian component pods with the following command.
kubectl -n my-appian-site get pods
The STATUS of the Appian component pods will transition from Pending to Running. When the Appian site is ready, you should see all pods have READY of 1/1 and STATUS of Running, similar to the following.
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NAME READY STATUS RESTARTS AGE
appian-k8s-appn-data-server-0-0 1/1 Running 0 15m
appian-k8s-appn-httpd-8658f7fdb7-k9f6j 1/1 Running 0 15m
appian-k8s-appn-httpd-bf56974d4-crv4g 1/1 Running 0 15m
appian-k8s-appn-kafka-0-0 1/1 Running 2 15m
appian-k8s-appn-search-server-0-0 1/1 Running 2 15m
appian-k8s-appn-service-manager-0-0 1/1 Running 3 15m
appian-k8s-appn-webapp-0-0 1/1 Running 0 15m
appian-k8s-appn-zookeeper-0-0 1/1 Running 0 15m
mariadb-appian-mariadb-0 1/1 Running 0 21m
Get the appians custom resource to check the status of your Appian site.
kubectl get -n my-appian-site appians
The STATUS of a starting site will transition from not set to Creating to Starting to Ready. The transition from not set to Creating to Starting should happen within seconds. The transition from Starting to Ready should happen within 20 to 30 minutes.
Make sure the STATUS is Ready before accessing your site, similar to:
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NAME URL STATUS
appian-k8s-appn http://myappiansite.com Ready
If you have any trouble with creating the Appian site, see Troubleshooting Appian on Kubernetes.
If you need to edit the Appian CR and restart, see Editing, Stopping, and Restarting.
Newly created sites are bootstrapped with a system administrator user. This user cannot access the Administration Console. The steps below detail how to login, then create a new system administrator user that can access the Administration Console.
<URL>/suite/design/users where <URL> is the value you set in the .spec.webapp.url field of the Appian custom resource.Administrator and temporary password admin. Change the user’s password when prompted to do so.To stop the Appian site, see Stopping the Appian site.
As noted in the supported database list, Appian supports the following relational databases:
To be able to communicate with your relational database, Appian requires a compatible RDBMS/JDBC driver. The Webapp Docker image includes drivers for the latest supported versions of MariaDB, Oracle, Microsoft SQL Server, and PostgreSQL. It does not, however, include drivers for MySQL or IBM Db2.
If you’d like to use either MySQL or IBM Db2 as the Appian/primary or a business data source, you’ll need to use the Appian CRD support for specifying init containers. The same goes for older supported versions of MariaDB, Oracle, Microsoft SQL Server, and PostgreSQL that require different driver versions.
