Envoy

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Envoy

This guide covers the setup, configuration, and monitoring of the ClearPass extension for Envoy and the configuration of webhook in Envoy for the Integration with HPE Aruba Networking ClearPass. This guide walks through the v2 of this integration. We will also cover the migration steps from v1 to v2.

Envoy Visitors is a visitor management platform for a modern front desk which helps streamline visitor Sign-in. When visitors arrive, Envoy makes it easy for them to Sign-in, presents them with relevant forms where they can provide their information, sign documents (NDAs) and optionally notifies the person they are visiting of their arrival using an Email or SMS.

ClearPass is an industry leading Guest Management solution that delivers secure, automated guest access workflows. It’s very useful for an enterprise to combine these two applications to get a seamless visitor management system that automates visitor’s Wi-Fi requirements.

This Extension serves two primary use-cases

1. Creates a guest account upon Visitor Sign In

2. Disables a guest account upon Visitor Sign Out

With Envoy hosted in the cloud and ClearPass sitting primarily on-prem, there are challenges in making these two applications communicate in real time so that a visitor receives guest Wi-Fi credentials from ClearPass as soon as he registers using Envoy Visitors application. Traditionally the apps would communicate using APIs where an application would request information which is usually followed by a response. Hence in order to get real-time information you have to poll or request as often as possible which is not scalable. The answer or the solution is a webhook which does not wait for a request to send information but sends the data as soon as it’s available.

Before we proceed with the flow, we need to understand the concept of webhooks and skyhook.

What is a webhook?

A webhook (also called a web callback or HTTP push API) is a way for an app to provide other applications with real-time information. A webhook delivers data to other applications as it happens, meaning you get data immediately.

What is skyhook?

Skyhook was developed to overcome the inability for cloud-based applications to send events [webhooks] directly into a ClearPass that was typically deployed on the trust side of a corporate firewall. In short, it is a service that runs in AWS. ClearPass nodes running on-prem, use extensions to open a persistent connection into Skyhook to receive the events originally sent from a 3rd party cloud application specific for that customer/tenant.

As an overview, Envoy running in the cloud will send a webhook upon a Visitor Sign in or a Sign out event. This will communicate with skyhook. The ClearPass extension configured and installed will maintain a persistent connection with skyhook awaiting an event (Sign in/ Sign out).

Software Requirements

The minimum software version required for CPPM is 6.11.0 . At the time of writing, version 6.11.10 is available as the long supported release and 6.12.4 is available as the short supported release. CPPM runs on hardware appliances with pre-installed software or as a Virtual Machine under the following hypervisors. Hypervisors that run on a client computer such as VMware Player are not supported.

• VMware vSphere Hypervisor (ESXi) 7.0 U3c and 8.0

• Windows Server 2019 with Hyper‑V and Windows Server 2022 with Hyper‑V.

• KVM on CentOS Stream 8, CentOS Stream 9, Ubuntu 20.04 LTS, and Ubuntu 22.04 LTS.

ClearPass Installation and Deployment Guide

This document assumes your ClearPass environment is already configured and operational. If you require assistance with basic deployment, refer to the following deployment guide:

https://arubanetworking.hpe.com/techdocs/ClearPass/6.11/Installation-Guide/Default.htm

ClearPass Extensions

The integration between ClearPass Policy Manager and external systems is driven through a ClearPass capability known as Extensions, a sub-component of the ClearPass Exchange Integration framework. ClearPass Extensions are micro-services running on top of the base ClearPass platform. These micro-services enable HPE Aruba Networking to deliver new features outside of the main software release cycle and facilitate a faster time to market for specific features and integrations. Configuration and control of ClearPass Extensions is accomplished through the ClearPass Guest GUI, as covered later in this document.

Installing Extension

ClearPass Extensions are easy to install from the ClearPass Extensions Store. In a cluster, ClearPass Extensions can be installed on a subscriber independently of the publisher. Multiple copies of the same extension can be installed if needed as well.

Access to the extension store

Access the Extension Store to download and install ClearPass extensions. The Extension store utilizes the same HPE Passport account credentials used to validate support entitlement in the Software Updates Por- tal. This is configured under Administration > Agents and Software Updates > Software Updates as shown below. Ensure that valid HPE Passport credentials have been entered in these fields to enable Ex- tension download capabilities.

Installing the Extension from Store

Extensions are installed from the extension page in ClearPass Guest, as shown below. Access it from Guest > Administration > Extensions

From here, click on ‘Install Extension’, and the search box below appears.

Enter “Intune” and click on ‘Search’, see the example below.

Click on the extension name and then click “Install.”

In the “Install Extension” dialog box, set the IP address if necessary, as described in section “Extensions and IP address configuration support” below. Do not check the box to start the extension at this time. Click the “Install” button.

In this example, we’ve not entered an IP address for the extension to use, if there is intent to use the extension as an authorization source set this value and ensure its set the same on all nodes where the Extension is deployed.

The extension will download and appear in a “Stopped” state. Notice the options to Start, Delete, Reinstall, Show Logs, and view Configuration. Click on “Configuration” to view settings.

After the extension has been installed, proceed to configure the extension

A copy of the default Extension configuration is shown above, this will need to be modified for your deployment.

Extensions and web proxy support

Extensions support communications with 3^rd parties via a web proxy. This adds incremental proxy functionality. If a proxy is defined in ClearPass Policy Manager, then an extension will inherit that configuration. See later in the document on how to disable the proxy inherited configuration.

Extensions and IP address configuration support

ClearPass uses a non-externally routed IP address range to communicate with the Extension. The default is 172.17.0.0/16. You may configure a different range, if desired. This is especially useful when deploying extensions across nodes within a cluster where there is the requirement for a fixed consistent IP address for the extension across the cluster.

Changing the “Extensions Network Address” range is only necessary if either the ClearPass MGMT or DATA interface are using an IP address in the extension default range of 172.17.x.x/12, or if ClearPass needs to communicate with some external device in that range.

To Configure the base Extension IP subnet within Policy Manager navigate to Administration > Server Manager > Server Configuration [chose your node] Service Parameters [ClearPass system service].

Configuration Steps

There are primarily 3 steps involved in getting this integration configured.

1. Register and request for a Skyhook tenant

2. Configuration of Envoy for Integration

3. Installation and Configuration of the Envoy Extension using GUI in ClearPass 6.7.X

It is assumed you have SMTP and SMS configured to allow ClearPass Guest to send visitor account details to the Visitor/Guest.

Step I: Register and Request for a Skyhook Tenant ID

Skyhook Tenant ID’s can be registered in the skyhook self-service portal by accessing the following link https://clearpass.arubanetworks.com/webhooks/skyhook and instructions on using the skyhook self-service portal is available here: https://arubanetworking.hpe.com/techdocs/NAC/clearpass/integrations/clearpass-extension/skyhook-self-service-portal/

Kindly copy the skyhookTenant and the dbAccessToken in a text file. This will be used for configuration of the extension in ClearPass as well as configuring the tenant details on the Envoy plugin.

Step II: Configuring Envoy for ClearPass Integration

Below are the configuration steps to follow.

• Login to Envoy using your credentials on https://dashboard.envoy.com

Select the Location you wish to integrate with ClearPass as highlighted below**.** Navigate to Integrations and “Install” the ClearPass plugin.

• Once the plugin is installed, click on Configure and follow the steps.

For the first step, copy the Envoy Plugin Install Token. This will be used for the extension configuration in ClearPass to perform health checks.

• For the next step, we need to use the skyhookTenant obtained in Step I from the email in Figure 8. Copy this value in the CLEARPASS TENANTNAME section as shown below.

Ensure that the default URL in the section SKYHOOK API HOST matches with https://skyhook.clearpassbeta.com/api/skyhook/envoy. Do not edit the field if it does or unless instructed by TAC.

• Select the SMS Gateway that will be used to send the credentials to a visitor. We should use ClearPass SMS Gateway as an option here.

The other option is to use the Envoy SMS gateway (using Twilio). The SMS gateway used here uses the SMS template shown in the screenshot. This can be modified as per requirements. For this setup, we are going to use the ClearPass SMS Gateway.

• The last step shows the Status Report of the health checks performed by ClearPass extension.

ClearPass extension sends a health check every 5 minutes using the Envoy Plugin Install token for the given tenant. The statistics associated with this health check are shown here. This will only happen after the installation of the Envoy extension which is covered under the section Step III: Envoy Extension Installation and Configuration. Click on Complete Setup

Step III: Envoy Extension Installation and Configuration

After the extension has been installed, review the extension configuration as necessary and adjust as needed. Notice the options to Start, Delete, Reinstall or Show Logs and the option to review and set the extension configuration.

The default configuration used for extension is below

{

“skyhookTenant”: “0f4cxxxx-xxxx-xxxx-xxxx-2e04897691a8”,

“dbAccessToken”: “********”,

“envoyInstallToken”: “********”,

“countryIsoCode”: “US”,

“phoneNumberField”: “Your Phone Number”,

“cppmDefaultExpiryHrs”: 8,

“cppmGuestRoleName”: “[Guest]”,

“cppmGuestRoleId”: 2,

“cppmGuestSmsReceipt”: true,

“cppmGuestEmailReceipt”: true,

“cppmGuestAccessCode”: false,

“dbLogging”: false,

“logLevel”: “INFO”

}

A copy of the Envoy Extension with the desired configuration is shown below, this will need to be modified for your deployment. Include the skyhookTenant, dbAccessToken and envoyInstallToken that will be specific to your environment. Change any other default values if necessary. Select ‘Restart’ and click on Save Changes to restart the extension.

The table below explains each option with the values and examples required for configuration.

Extension configuration options

Configuration attribute	Description	Example/Values
skyhookTenant	The Skyhook tenant ID received in the registration email.	c7xxxxx8-b2b6-4125-9741-cxxxxxxxx38a6
dbAccessToken	The access token for Skyhook received in the registration email.	Long Random string like 7INXYr1YUixxxxxv...
envoyInstallToken	The install token from Envoy used for Health Checks to ensure a valid communication channel exists.	f2343xxx-xxxx-xxxx-xxxx-2abd3e415a12
CountryIsoCode	The country code to use for phone number formatitting when the number is not specified in the international format.	US, IN
phoneNumberField	The sign-in field from Envoy to use for the visitor phone number.	“Your Phone Number”
cppmDefaultExpiryHrs	The default number of hours for an account to be active.	8
cppmGuestRoleName	The role name to be used in ClearPass Guest when creating the account. This value should match with the cppmGuestRoleId	[Contractor], [Guest], [Employee], Custom Role
cppmGuestRoleId	This value sets the role id to use when creating guest accounts	1 - [Contractor], 2 - [Guest], 3 - [Employee], 4 - Custom Role
cppmGuestSmsReceipt	Sets the value of auto_send_sms for ClearPass to send the Guest credentials receipt via SMS	true/false
cppmGuestEmailReceipt	Sets the value of auto_send_smtp for ClearPass to send the Guest credentials receipt via SMTP	true/false
cppmGuestAccessCode	Enables creation of random codes as Guest Username. If not used the defaul email field is used as username.	true/false
dbLogging	Enables advanced logging of skyhook db connection	true/false
logLevel	Logging level for troubleshooting	"DEBUG", "INFO", "WARN", "ERROR"

After the configuration and the restart of the extension, click on Show Logs. You should see the following.

The above log states that the extension is now ready to process the events for Envoy.

You can change the logLevel to DEBUG under configuration for detailed logs. These are very useful for troubleshooting and should be included before raising a support case if necessary.

Envoy Sign-in flow

The configuration of Envoy Sign-in form is beyond the scope of this guide however there are a couple of interesting features introduced in Envoy v2 extension which requires us to go through this in brief. These features are not available in v1.

An Envoy Sign-in flow can be configured by selecting the location of your choice and then navigating to Visitors > Settings > Sign-in flow. Click on Sign-in fields.

The v2 extension now allows you to use any custom field as a Phone number field. This gives you the flexibility to change the name of the field displayed on the form. It can now be changed for example to “Mobile Number” or “Cellphone Number” or any other custom label. In v1 this was hardcoded and cannot be changed.

This field is then mapped to visitor_phone field in ClearPass Guest using the extension configuration parameter phoneNumberField as described in the “Extension configuration options” in Figure 19. It allows an administrator to effectively rename this field in Envoy and map the value to visitor_phone field in ClearPass Guest which is then used by ClearPass to SMS the credentials.

Envoy v2 extension can also consume information from other custom fields defined in the form. One can also add a custom field in the Sign-in form the input to which will be captured under the Guest account details within ClearPass. For instance, the custom field “Favourite Drink” is added to this form as shown in the figure. This can be added by clicking “Add a New Field” which is highlighted.

This is captured under Guest account details within ClearPass. Go to Guest > Manage Accounts, select a registered account and click on Show Details.

To add further, you can also use this field for the reports within Insight.

Migration Steps from Envoy v1 to Envoy v2

Envoy v1 was available as a ClearPass extension prior to writing this guide. Customers who already have v1 installed are recommended to move to v2 for performance enhancements. The v2 version of the Extension also provides an additional flexibility in defining custom fields as shown in Figure 22.

Following are the migration steps.

1. Request for a new SkyHook Tenant ID for Envoy v2 integration. The steps for the same are specified in the section “Step I: Register and Request for a Skyhook Tenant ID”.

2. Stop the Envoy v1 extension installed on your ClearPass server. Navigate to ClearPass Guest and go to Administration > Extensions. Click on the Envoy Extension to Stop it as shown below.

1. Install the new Envoy plugin for ClearPass Integration. Use the steps in the section “Step II: Configuring Envoy for ClearPass Integration”.

2. Follow the section “Step III: Envoy Extension Installation and Configuration” to install the new Envoy v2 extension.

3. Test the functionality for few days to ensure it works. If yes, the old extension can be deleted. If no, it can be restarted to ensure no service interruption. Contact support for any further assistance with troubleshooting.

Testing/Demo

Now that the components are all configured and ready to use, let’s walk through the experience from the visitor and administrator perspective. In order to do so, the first step for a visitor is to sign in using the Envoy Visitors app running on an iPad at a reception in the customer setup.

Configuring an iPad to assist customers with registration at front desk is beyond the scope of this document. Essentially, one needs to download the Envoy Visitors app from the appstore and register the device to your Envoy account.

Detailed steps are available here https://dashboard.envoy.com/devices/ipads/new

1. Visitor walks up to a tablet used for registration. Every company can personalize the branding by using their logos for the registration pages and email. A simple registration Sign-in page configured for our demo is shown below.

Visitor taps to sign in.

2. A first-time visitor is asked to fill the form completely with his details as shown below. The visitor is also asked to select the Sponsor, the person he is visiting. The sponsor is notified via an email/SMS of the visitor’s arrival. We have used basic forms here for demo. These forms are customizable and can be created as per customer requirements.

3. The next steps will ask the visitor to click a picture if configured and then make them digitally sign the required forms like NDA etc. There are several options available for the Sign-in flow on Envoy.

4. Once done, you will see a welcome message. This could be a message, image or a video based on the configuration on Envoy. The customization options are a part of the Sign-in flow. This finishes the registration from a visitor perspective.

5. Visitor should receive an email as well as an SMS with his credentials to login to guest Wi-Fi. Following is the snapshot of the email. Notice the account expiry time is set to 8 hours by default.

You can change the Receipt Template (Guest Manager Receipt) under Configuration > Receipts > Templates.

6. After the visit, user can Sign out at the registration desk using the same tablet. Type the first 3 letter of the name used during Sign in and select the user.

Now let’s see what happens in the backend from an administrator perspective.

1. Login to ClearPass Guest and go to Manage Accounts under Guest.

The new account has been created upon registration. Note the Expiration time, this should match with the Envoy extension configuration setting for cppmDefaultExpiryHrs. By default, it is set to 8 hours. Another thing to note is the Role which is set to [Guest]. This depends on the extension configuration settings for cppmGuestRoleName and cppmGuestRoleId. This could also be set to a custom Role value if required. The configuration for the same is beyond the scope of this guide.

2. If you enable DEBUG and Click on Show Logs under Extension, you should see the following details as a part of the Sign in event.

[2018-10-24T08:10:46.907] [INFO] envoy - [Sign In] The following guest signed in: clearpass.test@gmail.com

[2018-10-24T08:10:46.908] [DEBUG] envoy - Sending health check to https://app.envoy.com/platform/clearpass-staging/sign-in-callback?_juuid=8d089232-c25c-4b57-9aa3-xxxxxxxxxxx

[2018-10-24T08:10:46.908] [DEBUG] envoy - {“status”:“sign-in”,“visitor”:“Test User”,“username”:“clearpass.test@gmail.com”,“password”:30922,“tenant”:“3d72456d-fbd1-49cd-aa08- xxxxxxxxxxx “,“extId”:“313deebb-3807-45ee-ace8-f4e908fc83cb”}

[2018-10-24T08:10:47.373] [DEBUG] envoy - handleEnvoyHealthCheck Response: [202] payload: “ACCEPTED”

[2018-10-24T08:10:47.373] [INFO] envoy - Successfully called Envoy healthcheck

[2018-10-24T08:10:47.373] [DEBUG] envoy - Successfully sent healthcheck update to Envoy.

[2018-10-24T08:10:47.649] [DEBUG] envoy - Successfully deleted transaciton from realtime db.

3. Upon Sign out, the visitor account will be disabled. This can be validated under Manage Accounts in ClearPass Guest

4. The user’s Wi-Fi session should also get disconnected automatically upon Sign out. This depends on the policy configured for the Guest SSID. This configuration is beyond the scope of this document.

5. You would see a similar Sign out event in the DEBUG logs.

Appendix A – Troubleshooting and Support

Here we list some basic troubleshooting steps. If you need any help beyond this, please reach out to HPE Aruba Networking Support.

Check API Access Application Control restrictions

If you’ve previously hardened your ClearPass deployment with Application Access Controls, it’s possible that the Extension will not work. Reviewing the Extension Log might show something like the following after immediately starting the Extension. This likely indicates the ClearPass Application API’s are in place.

Example of Extension authorization failure due to Policy Manager Application Control:

[2020-03-16T15:42:21.083] [INFO] Intune - Server listening on port 80.

[2020-03-16T15:42:21.243] [DEBUG] Intune - Request “GET ‘https://172.17.0.1/api/server/version’” took 51.91ms.

[2020-03-16T15:42:21.245] [DEBUG] Intune - <!DOCTYPE html><html>

<head>

<title>

Error 403 (Forbidden)

</title>

<script language=“javascript”>

function reloadPage() {

var locHref = window.location.protocol + “//” + window.location.hostname;

window.location.href = locHref;

}

</script>

To resolve this issue, add the IP address of the Extension to the list of nodes permitted to access the API by navigating to Administration > Server Manager > Server Configuration {choose your node} > Network

Checking on the Extension Service

The ClearPass Extensions are supported by a system service which must be running.

Restarting this service will affect all deployed and running extensions.

To check on the state of the Extension Service, or to restart the service, go to Administration > Server Manager > Server Configuration > [SERVER] > Service Control. By default this service is automatically started.

Extensions and web proxy / firewall whitelisting

If ClearPass Policy Manager has been configured with a proxy, it’s still possible that domain whitelists are required, the same for some datacenter firewall to allow the installation of Extensions. Some enterprise customers maintain a whitelist of domain that are allowed to transit the proxy/firewall. The underlying docker configuration process uses standard docker registry access to pull images (hosted in docker hub). In general, the following hosts are used:

This is all also geo dependent to some degree and based on various AWS services, so AWS redirects and geo location services will vary. Finally, this all runs via standard HTTPS (port 443).

Extension Logs/Enable Debugging

If you have a requirement to access and view the logs from the Extension, you can turn on different logging levels from the Extension GUI. Adjust the logLevel to ‘DEBUG’ and restart the extension as shown below.

Logs can then be viewed from the ‘Show Logs’.

Remember after changing the logging level, as with any extension configuration change the extension will need to be restarted for this change to take effect.

Accessing the extension logs using ‘Collect Logs’ system function

In addition to viewing the logs as shown above, logs can also be collected and examined via the Policy Manager Collect Logs system function (Administration > Server Manager > Server Configuration > [Select SERVER] > Collect Logs). This is extremely useful should you have a need to call for technical assistance.

If the support team needs to investigate a system issue, one of the items they regularly ask for is the system logs to aid with their diagnostic investigation. By default the “logLevel” is set to INFO, but TRACE, DEBUG, INFO, WARN, ERROR, FATAL can also be set as required. Any of the levels will display the information for the selected state and lower; if INFO is selected, it will show messages for INFO, WARN, ERROR, FATAL.

After the logs have been collected, downloaded and expanded, you can locate the extension logs in the following location in the folder structure PolicyManagerLogs > extension > your-extension-id as shown below. Note the file-name is the same as the running instance ID of the extension.

Monitoring extension statistics

There is a way to monitor extension’s critical resource statistics with the configurable parameter added as part of the extension’s configuration. To enable extension statistics set the “enableStats” parameter to true. Remember a restart of the extension is need to activate the change anytime the config is modified.

To navigate to statistics page, click Show Details.

This will show statistics similar to the following:

Monitoring authorization performance

Since we are authorizing against an external system, it could be relevant to monitor the performance of these transactions as you setup and deploy. If you suspect there is a performance issue, ClearPass provides a way to monitor the authorization processing time. The graph below shows an example of this data, navigate to Monitoring > Live Monitor > System Monitor [click on ClearPass Tab, then select [Authorization]….

Appendix B – Considerations for Installing in a Cluster

Extensions are not synced between ClearPass cluster members, and thus must be installed on each member separately.

Some Extensions can run in two modes: Periodic Sync Mode and Authorization Source Mode.

Periodic Sync Mode

If you are configuring the extension to poll external system periodically and utilize the resulting ClearPass Endpoint database during endpoint Authorization, then you only need to install the extension on one cluster member, often the publisher.

You may wish to install the extension on a second cluster member as a backup, but remember that both extensions will individually be updating the endpoint database. You may want to stagger the updates between the two extensions, for example, Subscriber1 updates at the top of the hour and Subscriber2 updates at 30 minutes after the hour.

Also, in this mode there is no need to explicitly enter an IP address during installation. The defaults will suffice and ClearPass will select an IP in the range specified in the server configuration.

HTTP Authorization Source Mode

In this mode we configure an HTTP Auth source that results in a HTTPS call to external system during endpoint authorization. In this deployment model the extension must be installed on every cluster node that process authentications. Also in this scenario every cluster member’s extension must be set to the exact same IP address during installation time, as the HTTP Auth source configuration is propagated globally across all cluster members.

For example, if the extension IP range is 172.17.0.0/16, we would set the extension to 172.17.0.5 on every cluster member during installation of the extension.

While we normally want to avoid duplicate IP addresses in a network, this is not a concern with ClearPass extensions. Each ClearPass node communicates internally only with its own extension, and this traffic is not routed outside of ClearPass.

Subscriber nodes support the same ability as publishers to install an Extension from the Extension store.

Appendix C – endpoint sync schedule settings

The syncSchedule and similar scheduling parameters sets how often ClearPass executes certain actions like syncing or pushing endpoints. This setting is based on a slightly modified version of the CRON job scheduler found in Unix-like operating systems. It can be used to schedule jobs to run periodically at fixed times, dates or intervals.

A ‘cron’ is a job scheduler. Any scheduled task is called a ‘cron job’. The syntax for a cron job schedule is as follows:

In our use of the cron scheduler, we’ve dropped the use of the last instruction ≤command to execute> and use only the time/date functions, see below for a number of examples of scheduling a sync process.

• Schedule a sync to run at 2am daily:- 0 2 * * *

• Schedule a sync to run twice a day at 5am and 5pm:- 0 5,17 * * *

• Schedule a sync to run on every Sunday at 5pm:- 0 17 * * sun

• Schedule a sync to run every 30 minutes:- */30 * * * *

• Schedule a sync to run at 5pm on selected days:- 0 17 * * sun,fri

You can see from the above that the scheduling process is extremely flexible, alternatively https://crontab.guru/ is a great page for learning more about CRON scheduling.

Appendix D – Extension performance optimizations

Extensions are a critical part of ClearPass deployments today and with the increased dependency on extension interactions that involve periodic polling or real-time lookups, here are some of the best practice recommendations around optimizing overall performance when using extensions:

• If the extension is used to periodically poll external systems and populate endpoint repository, ensure that it is not installed in all the nodes in the cluster. Ideally these type of extensions should only be installed on the publisher node since only publisher node can add endpoint entries to the database. For redundancy, it can be installed on another additional node but it is recommended to stagger the polling interval so that both do not attempt to poll and update endpoint database at the same time.

  Example: 0 * * * *, This cron job runs at minute 0 of every hour (e.g., 00:00, 01:00, 02:00, etc.).

    30 * * * *, This cron job runs at minute 30 of every hour (e.g., 00:30, 01:30, 02:30, etc.).
  

• If the extension is used for looking up attributes from external systems in real time during authentication, it should be installed in all the nodes handling authentication. Note that the context server config is replicated from the publisher. When using extension for real time lookup, ensure that the extension has the same IP address in all the cluster nodes.

• If the extension is expected to do both real-time lookup and periodic polling, ensure that polling is enabled only on the publisher while the extension in subscribers can have the polling disabled by setting the “enableSyncAll” attribute to false.

     "enableSyncAll": false,
  

• Some 3rd party systems support fetching delta updates vs fetching all of the device information every polling cycle. The extensions that support fetching delta updates are: Workspace ONE Crowdstrike Falcon Microsoft Intune Mosyle SentinelOne Service Now

  For these extensions, the syncUpdatedOnly attribute should be set to true in extension config so that the number of DB updates in ClearPass is minimized

    "syncUpdatedOnly": true,
  

  For extensions that do not support syncUpdatedOnly, ensure that the sync interval is not aggressive. We recommend syncing at most twice a day and that too during off peak hours whenever a full sync is performed.

• Some 3rd party systems can be very noisy in terms of attribute updates. There could be certain attributes that keep changing every sync interval like “Free Memory in Bytes”, “Last Check in Time” etc. There is no value in updating endpoints when such trivial attributes change for the device. Hence it is recommended to use “ignoreEndpointDifferences” attribute in extension configuration to ignore change in attributes that you do not care about in terms of ClearPass policies.

  You can review the Audit Viewer in ClearPass under Monitoring > Audit Viewer to see what attributes are being updated for endpoints to check if there are unnecessary updates.

  Sample for JAMF extension:

    "ignoreEndpointDifferences": "Last Update, Report Date UTC, Last Contact Time UTC, Last Inventory Update UTC, Last Reported IP, IP Address",
  

  Default for Microsoft Intune extension:

    "ignoreEndpointDifferences": "Last Sync Date Time, Free Storage Space in Bytes",
  

• To further optimize the number of endpoints being updated in ClearPass, you can specify which attributes are being used in the ClearPass policies so that only changes to those attributes would trigger an update to the endpoint. This is done by listing out the specific attributes under endpointAttributes in extension configuration.

  Sample for JAMF extension:

    "endpointAttributes": "Group names, MDM Enabled, Managed, Remote Managed, Supervised, Serial Number",
  

• Setup extension to restart unless it was intentionally stopped. A restart policy can be defined in extension configuration to ensure that the extension starts up automatically after server reboots and such. Restart policy of “unless-stopped” would ensure the extension always starts up unless it was manually stopped.

  “restartPolicy”: “no” — The extension will not be automatically restarted after the server is restarted.

  “restartPolicy”: “always” — The extension will always be restarted after the server is restarted.

  “restartPolicy”: “unless-stopped” — The extension will be restarted unless it was stopped prior to the server restart, in which case it will maintain that state.

  “restartPolicy”: “on-failure:N” — If the extension fails to restart, the value for “N” specifies the number of times the extension should try to restart. If you do not provide a value for “N”, the default value will be “0”.

  The “restartPolicy” parameter is not present by default in extension configurations. When it is not present, if the system is restarted a default policy is applied to the extension to maintain the state it was in before the restart. If the “restartPolicy” parameter is added to the configuration but later removed, the extension will then revert to the default restart policy.