Inconsistent SSH access across devices after switching to new network setup

I recently changed some stuff with my home network, and the changes sparked a few general networking questions (below is a diagram of what I'm working with): - Context: - For both Setup A and Setup B, the ISP modem is *not* in Bridge mode. - *Setup A*: - local IP of the Pi was 10.0.0.9. - I was able to SSH from my laptop to the Pi using the 10.0.0.9 IP address. - I was able to SSH from the R320 to the Pi using the 10.0.0.9 IP address. - *During the transition from Setup A to Setup B*: - Local IP of wlan0 of the Pi was 10.0.0.9 - Local IP of eth0 of the Pi was 10.0.0.8 - I was able to SSH from my laptop to the Pi using both 10.0.0.9 and 10.0.0.8. - *Setup B*: - According to my router: - 10.0.0.9 is the IP of prodpi (this is what I named the Pi when I installed the OS). - 10.0.0.8 is the IP of Raspberry Pi. I am unable to ping or SSH using this IP address. - According to the TP-Link network: - 10.0.0.10 is the IP of prodpi - I am *unable* to SSH from my laptop or the R320 to 10.0.0.8 - I am *unable* to SSH from my laptop to 10.0.0.9, however I am able to SSH from the R320 to 10.0.0.9. - I am able to SSH from my laptop and the R320 to 10.0.0.10. - Questions: - Do IP addresses point to a specific machine, or do they point to a specific *network interface on a specific machine*? - Why would I be able to SSH to 10.0.0.9 from the R320, but not my laptop in Setup B? - Why does my router say 10.0.0.8 is assoicated with a Raspberry Pi host, but I can't ping it?