Here is a Telegram thread where Trey discusses the need for having a unique IP address for each node you are running.
public vs. private IP addresses:
If you’re running a node at home, most people pay their ISP (internet service provider) for one IP address. For example 126.96.36.199. You then plug in a router, which takes creates an INTERNAL network in your home, that will assign different internal IP addresses to each device that connects to the router. For example, laptop = 192.168.1.100, desktop = 192.168.1.101, smart-tv = 192.168.1.12. If you are running Docker on your computer, it can further create an internal network within your computer for different docker instances, for example: presearch-node = 188.8.131.52, presearch-auto-updater = 184.108.40.206, some-other-container = 220.127.116.11
When the containers in Docker communicate out to your router, the traffic all comes FROM the IP address of your computer (i.e. 192.168.1.100), and when your computer reaches out to the internet, the traffic all comes FROM the IP address your ISP assigned to your router (i.e. 18.104.22.168), which is your “public ip address” as it is used to connect out to the public internet.
In some cases, people may even have multiple routers in their home nested. This process of creating private networks within networks is called Network Address Translation (NAT) if you want to look it up.
But the point is that most people only have ONE public IP that they pay for at their homes, so when we say that there is a strict limit of one node per IP, unless you are paying your ISP for multiple IP addresses that your devices can use (not common) then you can only run one node at your home.
For nodes with a hosting provider, you’ll typically have a unique public ip per server, but for folks hosting at home, I wanted to post the above to prevent any confusion and to explain why some of you may be seeing your nodes “blocked”. The update rolling out shortly will provide a very clear error message when your node is blocked due to duplicate nodes running with the same public IP.