Hi, I have my Umbrel node running on a RasperryPI4.
I would like to connect to a friend´ s Linux node and also my friend could connect to my Umbrel node If it is possible.
Can someone help me to tell how I can add the address of my friend´ s node to include it as my peer?
What address should I give it to include my node?
Thank you!
Are you referring to add it as blockchain sync peer?
In the troubleshooting manual I explain it how to add manually another node IP to sync faster your blockchain copy.
Enter SSH into your new Umbrel node, then:
cd umbrel
sudo docker exec bitcoin bitcoin-cli addnode "192.168.x.x:8333" "onetry"
replace “192.168.x.x” with your existing running node IP.
This will make your new node to sync directly from your old running node, without need to be connected to internet, if you have a slow connection or Tor is making problems.
Once is finished, you can remove the IP from peers and go back to normal connection.
Give friends your onion address and your login password… 
Is it possible to replace the IP in that command to an onion address?