If your SNMP polling station is outside of VDOM1 (i.e. it does not connect directly to the sub-interface) then just poll on port1. You don't need to poll the sub interface. SNMPwalk on port1 will give you all the same details.
But yes to answer your other concern, you absolutely need routes and fw policies to allow traffic to and from different VDOMs.
@gflemingI've followed what you have said, and checked my articles. I've now made my VDOM 1 the management VDOM. And I was hoping this would then accept the SNMP queries & traps but it didn't. I may leave this post open to let others see it and share there input.
I have Solarwinds polling the device which is a good start.
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