Chapter 1. Red Hat build of Cryostat Operator


You can use the Red Hat build of Cryostat Operator to manage and configure your Cryostat instance. The Red Hat build of Cryostat Operator is available on the OpenShift Container Platform (OCP).

After you create or update a Cryostat application on the OpenShift Container Platform, the Red Hat build of Cryostat Operator creates and manages the Cryostat application.

Operator level 2 seamless upgrades

The Operator Capability Level for the Red Hat build of Cryostat Operator is set to Level 2 Seamless Upgrades on the Operator Lifecycle Manager framework. After you upgrade your Red Hat build of Cryostat Operator, the Red Hat build of Cryostat Operator automatically upgrades Cryostat and its related components. The automatic upgrade operation does not remove any JFR recordings, templates, rules, and other stored components, from your Cryostat instance.

Note

The automatic upgrade operation occurs only for minor releases or patch update releases of Cryostat. For major releases, you might need to re-install the Red Hat build of Cryostat Operator.

Persistent volume claims

You can create persistent volume claims (PVCs) on Red Hat OpenShift with the Red Hat build of Cryostat Operator so that your Cryostat application can store archived recordings on a cloud storage disk.

Operator configuration settings

Additionally, you can make the following changes to the default configuration settings for the Red Hat build of Cryostat Operator:

  • Configure the PVC that was created by the Red Hat build of Cryostat Operator, so that your Cryostat application can store archived recordings on a cloud storage disk.
  • Configure your Cryostat application to trust TLS certificates from specific applications.
  • Disable cert-manager, so that the operator does not need to generate self-signed certificates for Cryostat components.
  • Install custom event template files, which are located in ConfigMaps, to your Cryostat instance, so you can use the templates to create recordings when Cryostat starts.

The following configuration options for the Red Hat build of Cryostat Operator are included:

  • Resource requirements, which you can use to specify resource requests or limits for the core, datasource, grafana, storage, db, or auth-proxy containers.
  • Service customization, so that you can control the services that the Red Hat build of Cryostat Operator creates.
  • Sidecar report options, which the Red Hat build of Cryostat Operator can use to provision one or more report generators for your Cryostat application.

Single-namespace or multi-namespace Cryostat instances

The Red Hat build of Cryostat Operator provides a Cryostat API that you can use to create Cryostat instances that work in a single namespace or across multiple namespaces. You can control these Cryostat instances by using a GUI that is accessible from the Red Hat OpenShift web console.

Note

From Cryostat 3.0, the Cryostat API supports the creation of both single-namespace and multi-namespace instances. The Cluster Cryostat API that you could use to create multi-namespace instances in Cryostat 2.x releases is deprecated and superseded by the Cryostat API in Cryostat 3.x.

Users who can access the multi-namespace Cryostat instance have access to all target applications in any namespace that is visible to that Cryostat instance. Therefore, when you deploy a multi-namespace Cryostat instance, you must consider which namespaces to select for monitoring, which namespace to install Cryostat into, and which users can have access rights.

Prerequisites for configuring the Red Hat build of Cryostat Operator

Before you configure the Red Hat build of Cryostat Operator, ensure that the following prerequisites are met:

  • Installed the Red Hat build of Cryostat Operator in a project on Red Hat OpenShift.
  • Created a Cryostat instance by using the Red Hat build of Cryostat Operator.

1.2. Disabling cert-manager

You can disable cert-manager functionality by configuring the enableCertManager property of the Red Hat build of Cryostat Operator.

By default, Red Hat build of Cryostat Operator’s enableCertManager property is set to true. This means that the Red Hat build of Cryostat Operator uses the cert-manager CA issuer to generate self-signed certificates for your Cryostat components. The Red Hat build of Cryostat Operator uses these certificates to enable HTTPS communication among Cryostat components operating in a cluster.

You can set the enableCertManager property to false, so that the Red Hat build of Cryostat Operator does not need to generate self-signed certificates for Cryostat components.

Important

If you set the enableCertManager property to false, you could introduce potential security implications from unencrypted internal traffic to the cluster that contains your running Cryostat application.

Prerequisites

  • Logged in to the OpenShift Container Platform by using the Red Hat OpenShift web console.

Procedure

  1. If you want to start creating a Cryostat instance, perform the following steps:

    1. On your Red Hat OpenShift web console, click Operators > Installed Operators.
    2. From the list of available Operators, select Red Hat build of Cryostat.
    3. On the Operator details page, click the Details tab.
    4. In the Provided APIs section, select Cryostat, and then click Create instance.
  2. On the Create Cryostat panel, to configure the enableCertManager property, choose one of the following options:

    1. If you want to use the Form view:

      1. Click the Form view radio button.
      2. Set the Enable cert-manager Integration switch to false, and then enter a value in the Name field.

        Figure 1.1. Toggling the Enable cert-manager Integration switch to false

    2. If you want to use the YAML view:

      1. Click the YAML view radio button.
      2. In the spec: key set of the YAML file, change the enableCertManager property to false.

        Example of configuring the spec: key set in a YAML file

        --
        apiVersion: operator.cryostat.io/v1beta2
        kind: Cryostat
        metadata:
          name: cryostat-sample
        spec:
          enableCertManager: false
        --
        Copy to Clipboard Toggle word wrap

  3. If you want to configure other properties in the custom resource (CR) for this Cryostat instance, see the other sections of this document for more information about these properties.
  4. If you want to finish creating this Cryostat instance, click Create.

When you click Create, this Cryostat instance is available under the Cryostat tab on the Operator details page. You can subsequently edit the CR properties for a Cryostat instance by clicking the instance name on the Operator details page and then select Edit Cryostat from the Actions drop-down menu.

The Red Hat build of Cryostat Operator automatically restarts your Cryostat application, enabling the application to run with the updated enableCertManager property configuration.

Verification

  1. Select your Cryostat instance from the Cryostat tab on the Operator details page.
  2. Navigate to the Cryostat Conditions table.
  3. Verify that the TLSSetupComplete condition is set to true and that the Reason column for this condition is set to CertManagerDisabled. This indicates that you have set the enableCertManager property to false.

    Figure 1.2. Example showing the TLSSetupComplete condition set to true

1.3. Customizing event templates

You can configure the eventTemplates property of the Red Hat build of Cryostat Operator YAML configuration file to include multiple custom templates. An event template outlines the event recording criteria for your JDK Flight Recording (JFR). You can configure a JFR through its associated event template.

By default, Red Hat build of Cryostat Operator includes some pre-configured event templates. These pre-configured event templates might not meet your needs, so you can use Red Hat build of Cryostat Operator to generate custom event templates for your Cryostat instance and store these templates in ConfigMaps for easier retrieval. You can generate a custom event template in the following ways:

  • Use the Red Hat OpenShift web console to upload an event template into a custom resource.
  • Edit the YAML file for your Cryostat custom resource on the Red Hat OpenShift web console.

After you store a custom event template in a ConfigMap, you can deploy a new Cryostat instance with this custom event template. You can then use your custom event template with JFR to monitor your Java application to meet your needs.

Prerequisites

  • Logged in to the OpenShift Container Platform by using the Red Hat OpenShift web console.
  • Logged in to your Cryostat web console.

Procedure

  1. To download a default event template, navigate to your Cryostat web console and from the Events menu, click Downloads.

    Note

    Event templates are in XML format and have a file name extension of .jfc.

  2. Optional: If you want a custom event template, edit the downloaded default event template by using a text editor or XML editor to configure the template to meet your needs.
  3. Log in to your Red Hat OpenShift web console by entering the oc login command in your CLI.
  4. Create a ConfigMap resource from the event template by entering the following command in your CLI. You must issue the command in the path where you want to deploy your Cryostat application. You can use this resource to store an event template file that is inside the cluster where you run your Cryostat instance.

    Example of creating a ConfigMap resource by using the CLI

    $ oc create configmap <template_name> --from-file=<path_to_custom_event_template>
    Copy to Clipboard Toggle word wrap

  5. If you want to start creating a Cryostat instance, perform the following steps:

    1. On your Red Hat OpenShift web console, click Operators > Installed Operators.
    2. From the list of available Operators, select Red Hat build of Cryostat.
    3. On the Operator details page, click the Details tab.
    4. In the Provided APIs section, select Cryostat, and then click Create instance.
  6. On the Create Cryostat panel, to upload an event template in XML format into a resource, choose one of the following options:

    1. If you want to use the Form view:

      1. Click the Form view radio button.
      2. Navigate to the Event Templates section of the Cryostat instance.
      3. From the Event Templates menu, click Add Event Template. An Event Templates section opens on your Red Hat OpenShift console.
      4. From the Config Map Name drop-down list, select the ConfigMap resource that contains your event template.

        Figure 1.3. Event Templates option for a Cryostat instance

      5. In the Filename field, enter the name of the .jfc file that is contained within your ConfigMap.
    2. If you want to use the YAML view:

      1. Click the YAML view radio button.
      2. Specify any custom event templates for the eventTemplates property. This property points the Red Hat build of Cryostat Operator to your ConfigMap, so that the Red Hat build of Cryostat Operator can read the event template.

        Example of specifying custom event templates for the eventTemplates property

        --
        apiVersion: operator.cryostat.io/v1beta2
        kind: Cryostat
        metadata:
          name: cryostat-sample
        spec:
          eventTemplates:
          - configMapName: custom-template1
            filename: my-template1.jfc
          - configMapName: custom-template2
            filename: my-template2.jfc
        --
        Copy to Clipboard Toggle word wrap

        Important

        You must select the name of a ConfigMap, which is associated with your Cryostat or Cluster Cryostat instance, from the configMapName drop-down list. Additionally, you must specify a key associated with the ConfigMap in the filename field.

  7. If you want to configure other properties in the custom resource (CR) for this Cryostat instance, see the other sections of this document for more information about these properties.
  8. If you want to finish creating this Cryostat instance, click Create.

When you click Create, this Cryostat instance is available under the Cryostat tab on the Operator details page. You can subsequently edit the CR properties for a Cryostat instance by clicking the instance name on the Operator details page and then select Edit Cryostat from the Actions drop-down menu.

The Red Hat build of Cryostat Operator can now provide the custom event template as an XML file to your Cryostat application. Your custom event template opens alongside default event templates in your Cryostat web console.

Verification

  1. On the Cryostat web console, click Events from the menu. If an Authentication Required window opens on your web console, enter your credentials and click Save.
  2. Under the Event Templates tab, check if your custom event template shows in the list of available event templates.

    Figure 1.4. Example of a listed custom event template under the Event Templates tab

1.4. Configuring TLS certificates

You can specify the Red Hat build of Cryostat Operator to configure Cryostat to trust TLS certificates from specific applications.

Cryostat attempts to open a JMX connection to a target JVM that uses a TLS certificate. For a successful JMX connection, the Cryostat must pass all its authentication checks on the target JVM certificate.

You can specify multiple TLS secrets in the trustedCertSecrets array of the Red Hat build of Cryostat Operator YAML configuration file. You must specify the secret located in the same namespace as your Cryostat application in the secretName property of the array. The certificateKey property defaults to tls.crt, but you can change the value to an X.509 certificate file name.

Important

Configuring a TLS certificate is required only for applications that have enabled TLS for remote JMX connections by using the com.sun.management.jmxremote.registry.ssl=true attribute.

Prerequisites

  • Logged in to the OpenShift Container Platform by using the OpenShift web console.
  • Logged in to your Cryostat web console.

Procedure

  1. If you want to start creating a Cryostat instance, perform the following steps:

    1. On your Red Hat OpenShift web console, click Operators > Installed Operators.
    2. From the list of available Operators, select Red Hat build of Cryostat.
    3. On the Operator details page, click the Details tab.
    4. In the Provided APIs section, select Cryostat, and then click Create instance.
  2. On the Create Cryostat panel, to configure a TLS certificate, choose one of the following options:

    1. If you want to use the Form view:

      1. Click the Form view radio button.
      2. In the Name field, specify a name for the instance of Cryostat that you want to create.
      3. Expand the Trusted TLS Certificates option, then click Add Trusted TLS Certificates. A list of options displays on your Red Hat OpenShift web console.

        Figure 1.5. The Trusted TLS Certificates option

      4. Select a TLS secret from the Secret Name list. The Certificate Key field is optional.

        Note

        You can remove a TLS certificate by clicking Remove Trusted TLS Certificates.

    2. If you want to use the YAML view:

      1. Click the YAML view radio button.
      2. Specify your secret, which is located in the same namespace as your Cryostat application, in the secretName property of the trustedCertSecrets array.

        Example of specifying a secret in the trustedCertSecrets array

        --
        apiVersion: operator.cryostat.io/v1beta2
        kind: Cryostat
        metadata:
          name: cryostat-sample
        spec:
          trustedCertSecrets:
          - secretName: my-tls-secret
        --
        Copy to Clipboard Toggle word wrap

      3. Optional: Change the certificateKey property value to the application’s X.509 certificate file name. If you do not change the value, the certificateKey property defaults to tls.crt.

        Example of changing the certificateKey property’s value

        --
        apiVersion: operator.cryostat.io/v1beta2
        kind: Cryostat
        metadata:
          name: cryostat-sample
        spec:
          trustedCertSecrets:
          - secretName: my-tls-secret
            certificateKey: ca.crt
        --
        Copy to Clipboard Toggle word wrap

  3. If you want to configure other properties in the custom resource (CR) for this Cryostat instance, see the other sections of this document for more information about these properties.
  4. If you want to finish creating this Cryostat instance, click Create.

When you click Create, this Cryostat instance is available under the Cryostat tab on the Operator details page. You can subsequently edit the CR properties for a Cryostat instance by clicking the instance name on the Operator details page and then select Edit Cryostat from the Actions drop-down menu.

The Red Hat build of Cryostat Operator automatically restarts your Cryostat instance with the configured security settings.

Verification

  1. Determine that all your application pods exist in the same OpenShift cluster namespace as your Cryostat pod by issuing the following command in your CLI:

    $ oc get pods
    Copy to Clipboard Toggle word wrap
  2. Log in to the web console of your Cryostat instance.
  3. On the Dashboard menu for your Cryostat instance, select a target JVM from the Target list.
  4. In the navigation menu on the Cryostat web console, select Recordings. On the Authentication Required dialog window, enter your secret’s credentials and then select Save to provide your credentials to the target JVM.

    Note

    If the selected target has password authentication enabled for JMX connections, you must provide the JMX credentials for the target JVM when prompted for a connection.

    Cryostat connects to your application through the authenticated JMX connection. You can now use the Recordings and Events functions to monitor your application’s JFR data.

1.5. Changing storage volume options

You can use the Red Hat build of Cryostat Operator to configure storage volumes for your Cryostat or Cluster Cryostat instance. Cryostat supports persistent volume claim (PVC) and emptyDir storage volume types.

By default, Red Hat build of Cryostat Operator creates a PVC for your Cryostat or Cluster Cryostat instance that uses the default StorageClass resource with 500 mebibytes (MiB) of allocated storage.

You can create a custom PVC for your Cryostat application on OpenShift Container Platform by choosing one of the following options:

  • Navigating to Storage Options > PVC > Spec in the Form view window, and then customizing your PVC by completing the relevant fields.
  • Navigating to the YAML view window, and then editing the storageOptions array in the spec: key set to meet your needs.
Note

You can learn more about creating a custom PVC by navigating to Changing storage volume options in the Using the Red Hat build of Cryostat Operator to configure Cryostat guide.

You can configure the emptyDir storage volume for your Cryostat application on OpenShift Container Platform by choosing one of the following options:

  • Enabling the Empty Dir setting in Storage Options on the Form view window.
  • Setting the spec.storageOptions.emptyDir.enabled to true in the YAML view window.

Prerequisites

  • Logged in to the OpenShift Container Platform by using the Red Hat OpenShift web console.

Procedure

  1. If you want to start creating a Cryostat instance, perform the following steps:

    1. On your Red Hat OpenShift web console, click Operators > Installed Operators.
    2. From the list of available Operators, select Red Hat build of Cryostat.
    3. On the Operator details page, click the Details tab.
    4. In the Provided APIs section, select Cryostat, and then click Create instance.
  2. On the Create Cryostat panel, to change storage settings for your Cryostat application, choose one of the following options:

    1. If you want to use the Form view:

      1. Click the Form view radio button.
      2. Navigate to the Storage Options section, and enter a value in the Name field.
      3. Expand Storage Options and click Empty Dir. An expanded selection of options opens on your Red Hat OpenShift web console.
      4. Set the Enabled switch to true.

        Figure 1.6. Example showing the Empty Dir switch set to true

    2. If you want to use the YAML view:

      1. Click the YAML view radio button.
      2. In the spec: key set of the YAML file, add the storageOptions definition and set the emptyDir property to true.

        Example showing the emptyDir property set as true

        --
        apiVersion: operator.cryostat.io/v1beta2
        kind: Cryostat
        metadata:
          name: cryostat-sample
        spec:
          storageOptions:
            emptyDir:
              enabled: true
              medium: "Memory"
              sizeLimit: 1Gi
        --
        Copy to Clipboard Toggle word wrap

      3. Optional: Set values for the medium and sizeLimit properties.
  3. If you want to configure other properties in the custom resource (CR) for this Cryostat instance, see the other sections of this document for more information about these properties.
  4. If you want to finish creating this Cryostat instance, click Create.

When you click Create, this Cryostat instance is available under the Cryostat tab on the Operator details page. You can subsequently edit the CR properties for a Cryostat instance by clicking the instance name on the Operator details page and then select Edit Cryostat from the Actions drop-down menu.

The Red Hat build of Cryostat Operator creates an EmptyDir volume for storage instead of creating a PVC for your Cryostat instance.

1.6. Scheduling options for Cryostat

From the Red Hat OpenShift web console, you can use the Red Hat build of Cryostat Operator to define policies for scheduling a Cryostat application and its generated reports to nodes.

You can define Node Selector, Affinities, and Tolerations definitions in the YAML configuration file for a Cryostat or Cluster Cryostat custom resource (CR) on Red Hat OpenShift. You must define these definitions under the spec.SchedulingOptions property for the Cryostat application and the spec.ReportOptions.SchedulingOptions property for the report generator sidecar. By specifying the SchedulingOptions property, the Cryostat application and its report generator sidecar pods will be scheduled on nodes that meet the scheduling criteria.

a targeted node application can receive sidecar reports updates from a Cryostat instance.

Example that shows the YAML configuration for a Cryostat CR that defines schedule options

kind: Cryostat
apiVersion: operator.cryostat.io/v1beta2
metadata:
  name: cryostat
spec:
  schedulingOptions:
    nodeSelector:
      node: good
    affinity:
      nodeAffinity:
        requiredDuringSchedulingIgnoredDuringExecution:
          nodeSelectorTerms:
          - matchExpressions:
            - key: node
              operator: In
              values:
              - good
              - better
      podAffinity:
        requiredDuringSchedulingIgnoredDuringExecution:
        - labelSelector:
            matchLabels:
              pod: good
          topologyKey: topology.kubernetes.io/zone
      podAntiAffinity:
        requiredDuringSchedulingIgnoredDuringExecution:
        - labelSelector:
            matchLabels:
              pod: bad
          topologyKey: topology.kubernetes.io/zone
    tolerations:
    - key: node
      operator: Equal
      value: ok
      effect: NoExecute
  reportOptions:
    replicas: 1
    schedulingOptions:
      nodeSelector:
        node: good
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: node
                operator: In
                values:
                - good
                - better
        podAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - labelSelector:
              matchLabels:
                pod: good
            topologyKey: topology.kubernetes.io/zone
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - labelSelector:
              matchLabels:
                pod: bad
            topologyKey: topology.kubernetes.io/zone
      tolerations:
      - key: node
        operator: Equal
        value: ok
        effect: NoExecute
Copy to Clipboard Toggle word wrap

Alternatively, you can open your Red Hat OpenShift web console, create a Cryostat instance, and then define Affinities and Tolerations definitions in the SchedulingOptions and reportOptions.SchedulingOptions options for that Cryostat instance.

Figure 1.7. The Report Options and Scheduling Options panels on the OpenShift web console

Back to top
Red Hat logoGithubredditYoutubeTwitter

Learn

Try, buy, & sell

Communities

About Red Hat Documentation

We help Red Hat users innovate and achieve their goals with our products and services with content they can trust. Explore our recent updates.

Making open source more inclusive

Red Hat is committed to replacing problematic language in our code, documentation, and web properties. For more details, see the Red Hat Blog.

About Red Hat

We deliver hardened solutions that make it easier for enterprises to work across platforms and environments, from the core datacenter to the network edge.

Theme

© 2025 Red Hat