How can I connect two Erlang/Elixir-nodes of two different machines via network connection?
54
votes
2 Answers
66
votes
You have to name your nodes and use the same cookie on both nodes.
In machine 1:
iex --name [email protected] --cookie a_cookie_string
In machine 2:
iex --name [email protected] --cookie a_cookie_string
Now the two machines can communicate. To test it, you can do something like this, on machine1:
iex([email protected])1> Node.connect :"[email protected]"
true
iex([email protected])2> print_node_name = fn -> IO.puts Node.self end
#Function<erl_eval.20.80484245>
iex([email protected])3> Node.spawn(:"[email protected]", print_node_name)
[email protected]
#PID<7789.49.0>
Domain names machine1.com and machine2.com can be changed with the ip addresses of the machines as well.
5
votes
If you are trying to connect Nodes via code:
You need to turn your running code into a distributed node. To do this run Node.start(:fullNameOfServer).
Eg: if your IP is 192.168.0.1, you can have a full Node name like :"[email protected]"
Once you turn your node into a distributed node, you set the cookie:
Node.set_cookie :cookie_name
Finally, you need to establish a connection with the remote Node. (You also need to Node.start and Node.set_cookie on the remote node)
To do this, you need the remote node's name. Let us assume the remote node's name is [email protected] (assuming this Node is another computer on the same local network). The code to do this, looks like Node.connect :"[email protected]"
You can now run Node.list to see the [email protected] available on [email protected] and vice versa.
Summarising the above points, your code should look something like
On the Foo machine
Node.start :"[email protected]" #this is the IP of the machine on which you run the code
Node.set_cookie :cookie_name
Node.connect "[email protected]"
On the Bar machine
Node.start :"[email protected]"
Node.set_cookie :cookie_name
