On your NetApp arrays, you can specify the Tivoli server as an SNMP traphost. It will then send all SNMP traps to the Tivoli server.
> snmp traphost xxx.xxx.xxx.xx
You might also look into using the SMI-S interface for NetApp arrays. You can find instructions for obtaining the NetApp SMI-S Agent at the following:
Data ONTAP Storage Management Initiative Specification (SMI-S) Agent is a command-based interface that detects and manages platforms that run Data ONTAP. It uses Web-Based Enterprise Management (WBEM) protocols to manage, monitor, and report about storage elements by type. SMI-S Agent follows schemas standardized by two organizations: Distributed Management Task Force (DMTF) and Storage Networking Industry Association (SNIA). You can install Data ONTAP SMI-S Agent (SMI-S Agent) on a Windows® or a Linux® host.