Wildcard DNS resolution issue

[amallick]

I am running into an issue where ServiceNow is unable to connect to an endpoint where the host resolves to a wildcard DNS record (e.g. *.domain.com). I see a Java UnknownHostException error in the logs. Any one has seen this?

[Tanushree Maiti]

Hi @amallick 

Refer KB: KB2091827 Outbound API Request Failure Due to UnknownHostException 

Resolution

Recommendation to resolve this type of issue:

Verify DNS Resolution

• Work with internal endpoint or networking team to verify whether the domain is publicly resolvable.
• Perform a ping or nslookup from your local machine or MID Server (if applicable) to validate DNS resolution.

Check Network Access

• If the domain is intended to be accessed internally only, ensure that the instance connects through a MID Server located within your internal network that can resolve internal domains.
• Confirm that the MID Server has appropriate DNS settings to reach internal domains.

Review Firewall and DNS Policies:

• Confirm with internal networking team if any firewall rules or DNS restrictions exist that might block external access to the domain.

Public DNS Registration:

• If the endpoint is intended to be accessible externally, verify that the domain is properly registered and reachable through public DNS servers.