The OpenNMS ServiceNow Plugin requires OpenNMS Horizon 31+ or OpenNMS Meridian 2023+.
ServiceNow
A ServiceNow instance with:
An OAuth2 application registry configured (client ID + client secret)
A token endpoint accessible from the OpenNMS server
REST API endpoints for alert and asset creation/update
Network
The OpenNMS server must be able to reach the ServiceNow REST API over HTTPS.
If the ServiceNow instance uses a self-signed or untrusted certificate, SSL validation can be disabled per-connection (not recommended in production).