Is it possible to forward only critical SNMP traps to an external server? How do I create such a filter? I am not sure how to create such a filter in the trap viewer snm
Do you need to forward traps based solely on severity or are there specific traps you wish to forward? If you want to forward specific traps, you should find the information you're looking for in the Configuring Trap Viewer Filters and Alerts section of the SolarWinds Orion Administrator Guide. I am not certain about forwarding based on severity though.
You would use the Trap Viewer, building a filter rule that only chooses those traps you consider Critical, and then setting a rule on it.
If you review the trap rules you'll see you can filter by device name(s), IP address or range, alarm type, and more.
You might need to build multiple rules, depending on your requirements.
Your first step is going to be determine what constitutes a Critical trap.