Checking Horizon Cloud Services Connectivity from Horizon Edge Gateway

It is important to remember that the Horizon Edge Gateway is not only used for enabling integration with Horizon Cloud Services, but it is also required in many environments for Horizon subscription licensing.

In modern deployments of Omnissa Horizon, subscription licenses are delivered through the Horizon Cloud control plane rather than through traditional license keys. To enable this mechanism, each Horizon pod must be connected to the cloud service using a Horizon Edge Gateway appliance.

When using subscription-based licensing:

• The Horizon Edge Gateway connects the Horizon pod to Horizon Cloud Services.
• The control plane synchronizes and delivers the Horizon license entitlement.
• No manual license key entry is required on the Connection Server.

For this reason, outbound connectivity to the Horizon Cloud endpoints is critical, not only for cloud services but also for maintaining a valid licensing state in subscription-based environments.

If the Edge Gateway cannot reach the required endpoints due to firewall restrictions, proxy configuration, or SSL inspection, administrators may experience issues such as:

• License synchronization failures
• Horizon services reporting licensing errors
• Problems during onboarding or control plane communication

In contrast, environments using term/perpetual license keys entered directly in the Horizon Console do not require a Horizon Edge Gateway, because licensing is handled locally within the pod.

 

Checking the connectivity

When deploying environments based on Omnissa Horizon integrated with Horizon Cloud Services (HCS), proper outbound connectivity from the Horizon Edge Gateway is critical.

This is the link for Port and Protocol Requirements for Deploying Horizon 8 Edge:

Port and Protocol Requirements for Deploying Horizon 8 Edge

In many enterprise environments, outbound communication toward the internet is tightly controlled through firewalls, proxies, or SSL inspection systems. While this is perfectly reasonable from a security perspective, it often introduces connectivity issues if the required endpoints are not properly allowed.

Even more commonly, the configuration works initially but breaks later because firewall rules are modified, security appliances are upgraded, or SSL inspection policies change over time.

For this reason, whenever issues arise with Horizon Cloud integration, the first thing to verify is whether the Edge Gateway can still reach the required Horizon Cloud Services endpoints.

Fortunately, the Edge Gateway provides a built-in diagnostic tool to help with exactly this scenario.

.

.

.

Using diagnostic.sh to Test Connectivity

The Horizon Edge Gateway includes a script called diagnostic.sh

This script performs a series of connectivity checks toward the Horizon Cloud Services endpoints required for proper operation.

The script validates:

• DNS resolution
• HTTPS connectivity
• Reachability of the required Horizon Cloud endpoints
• TLS handshake validation

This makes it extremely useful when troubleshooting issues caused by:

• Missing firewall rules
• SSL inspection interfering with TLS connections
• DNS resolution problems
• Proxy misconfigurations

.

Running the Diagnostic Script

Log in to the Horizon Edge Gateway via VM Web Console with the root account:

And run this command:

The script will test connectivity against multiple Horizon Cloud endpoints and return the results directly to the console.

A successful test typically shows results like:

If a problem exists, the script will clearly indicate which test failed.

.

Why This Check Is Important

Connectivity to Horizon Cloud Services is essential for several platform features, including:

• Edge Gateway registration
• Horizon control plane communication
• Monitoring and service updates
• Validate the Horizon License

Because firewall and security policies frequently evolve in enterprise environments, it’s a good practice to periodically validate connectivity using the diagnostic tool.

Running the diagnostic script can quickly confirm whether the issue is related to networking or to another component of the Horizon environment.

.

.

.

.

 Spoiler:

There may be proxy problems. For which proxy it is used, you can read this configuration file:

/opt/horizon/var/data/proxy.conf

.

.

.

Checking Horizon Cloud Services Connectivity from Horizon Edge Gateway

Configure Proxy Server for Horizon for SAML integration

When we need to integrate a Horizon infrastructure to the cloud identity provider (like Workspace One Access SaaS solution) sometimes we need to manage firewall and proxy configuration.

For the Firewall rule, there is much information (KB link) while for the proxy server, we are not able to use Windows server configuration because Horizon ignores it.

To use a proxy server to permit communication to the IdP URL from Horizon Connection servers we need to configure some values on ADAM DB:

pae-SAMLProxyName

pae-SAMLProxyPort

To connect to ADAM DB and where modify the correct value

  • Connect with RDP session to Connection Server OS
  • Start from PowerShell adsedit

A close-up of a computer screen

Description automatically generated

  • In the console tree select Connect to..

A screenshot of a computer

Description automatically generated

  • Configure the connection with this information.

dc=vdi,dc=vmware,dc=int

localhost:389

A screenshot of a computer

Description automatically generated

  • Expand ADAM ADSI tree under the object path: dc=vdi,dc=vmware,dc=int,ou=Properties,ou=Global
  • Click on value Common and modify the following value

pae-SAMLProxyName -> With Proxy URL

pae-SAMLProxyPort -> With Proxy Port

Now we can configure the SAML integration from Horizon and IdP

Some information about why we need to integrate and use Workspace One Access with Horizon:

Integration between VMware Horizon and VMware Workspace ONE Access (formerly called Workspace ONE) uses the SAML 2.0 standard to establish mutual trust, which is essential for single sign-on (SSO) functionality. When SSO is enabled, users who log in to VMware Workspace ONE Access or Workspace ONE with Active Directory credentials can launch remote desktops and applications without having to go through a second login procedure.

Configure Proxy Server for Horizon for SAML integration