You have few options:
Add this node as SNMP device and Run "List Resources". Fingers cross SolarWinds will detect something, but usually not everything. You can see all Hardware that SolarWinds was able to pick-up by adding "Current Hardware Health" resource on the node page.
You can create custom UnDP pollers. Research in forum how to set them up
My preferable. Get MIB file from the supplier and identify interesting OIDs you want to monitor and report on. Then - create SAM Template based on SNMP pollers and create as many components as you need to monitor key elements. The downside of it is that if you have many many many things that you want to monitor this will take you some time to setup as each OID will require separate component
Thanks for the reply. As per the understanding I have(not so very great with monitoring tools), SNMP MIB of QNAP is bare minimum. I ran some snmpwalks across the device and some values getting returned are in txt.
So, it will be some task to get it going.
Good, you now have to dig-in and understand what is inside your txt file. To help you with this you need MIB for your device (which you can most likely obtain from manufacture). Open it up with any text editor and just look for Objects IDs (OIDs) which you would like to monitor. Once you identify them - you can proceed with setting up UnDP in SolarWinds
The bottom line is - to set this up in solarwinds all you need is to know what Object ID(s) you want to monitor