I want to make sure I have this set up correctly so my cameras aren't calling China under my nose. 
Here's what I've got:
Blue Iris on a Windows 11 PC. It's hardwired to the main network router (172.16.blah.blah). It has a SECOND network card (192.168.1.x) that runs to a PoE switch then to all the cameras.
The cameras are a mix of Q-See (Dahua) and ReoLink cameras. (I have a Revotech mini camera coming too.)
Some will accept a blank default gateway entry. Others demand something in the same IP range as the camera's static IP address, so I can't just leave those blank.
What's the best practice?
Obviously, the ones that I can leave blank should be blank, but what should I set the "mandatory" default gateways to? 0.0.0.0, maybe if possible, but otherwise what? (I believe I read in a different thread in my hunting here today said that setting them to, say, 192.168.1.254—an unused address—will cause unnecessary traffic.)
And is there anything I should set in Windows or on my main router?
Oh, and FWIW, I do access BI from offsite using ZeroTier and also use a browser on the real LAN from a different room/device than the BI box.
Thanks!!
Andrew

Here's what I've got:
Blue Iris on a Windows 11 PC. It's hardwired to the main network router (172.16.blah.blah). It has a SECOND network card (192.168.1.x) that runs to a PoE switch then to all the cameras.
The cameras are a mix of Q-See (Dahua) and ReoLink cameras. (I have a Revotech mini camera coming too.)
Some will accept a blank default gateway entry. Others demand something in the same IP range as the camera's static IP address, so I can't just leave those blank.
What's the best practice?
Obviously, the ones that I can leave blank should be blank, but what should I set the "mandatory" default gateways to? 0.0.0.0, maybe if possible, but otherwise what? (I believe I read in a different thread in my hunting here today said that setting them to, say, 192.168.1.254—an unused address—will cause unnecessary traffic.)
And is there anything I should set in Windows or on my main router?
Oh, and FWIW, I do access BI from offsite using ZeroTier and also use a browser on the real LAN from a different room/device than the BI box.
Thanks!!
Andrew