I recently tested this using wireshark. When I run packet capture on nic1 of dstPC I see ping request packets coming, but no response packets leaving the interface. On nic2 I don't see any packets leaving either. So kind of stumped what is happening. It seems the computer just drops the response packet and it never makes it till any nic. But still don't have a good explanation of WHY the packet gets dropped.

OK this is what I was thinking too. So consider this scenario:

srcPCnic1 - 192.168.1.100/24 DG: 192.168.1.1 dstPCnic1 - 192.168.2.100/24 dstPCnic2 - 192.168.1.101/24 DG: 192.168.1.1

Topology: srcPCnic1 -> RTR -> dstPCnic1 Assume srcPCnic1 is also connected to dstPCnic2 via a switch. (Sorry if its difficult to imagine with the crude description)

On srcPC execute: ping 192.168.2.100 RTR will route the packet to dstPC. dstPC receives the packet on nic1. dstPC sends the Response packet via nic2.

Is the above understanding correct?

Not really. Just has to run till at least 5years at least. Since this will be deployed at customer site, pine64 and android both are not feasible. Thanks for the suggestion though.

Thanks. Will take a look.

Agreed. This is for customer site. At home i would do the same thing on a PI.

Thanks for these suggestions. Will look into them. Hopefully they are still manufactured and supported by the vendors.

So this will be deployed for customer sites. I dont think they will be happy with second hand stuff from ebay 😀 For my personal stuff i would have been happy with that though.

What replacement options you are looking at?