The private network cannot be connected

I built a private network, using two nodes on a local area network, one of which interrupted to expose port 4001 and used as a relay node. When I tried to connect to bootstrap to download files with other computers, there was no response. For example, node1 is bootstrap. Node2 uploads the file, uses other nodes to connect to add node1, and then the file of cat node2 has not responded. When I ping node2, the file is normal cat, how do I set it up?

Use this online guide helped me a lot

Thank you, but what I need is not this. I have set up a private network, and now other nodes are not in this LAN. When I connect to the bootstrap node, I cannot get the information of other nodes

Are you trying to setup a private ipfs network between peers which are not in the same network (LAN) ?
Did you find a solution? the issue is peers in private network cannot use public relays without them having the swarm key. I am trying to achieve the same with no luck as of yet.