ความปลอดภัยของระบบกระจายและคุกกี้

Connected Erlang nodes fully trust each other: any node can run code on any other. That power makes securing distribution essential.

Each node has a secret cookie. Two nodes can only connect if their cookies match. It is the basic authentication mechanism for clustering.

You can set the cookie at startup or at runtime. All nodes that should cluster must share the same value.

If not set explicitly, the VM reads ~/.erlang.cookie. It must have restrictive permissions or the VM refuses to start.

Nodes use -sname (short hostname) or -name (fully qualified). Both nodes must use the same scheme to connect.

A matching cookie only authenticates the connection. By default, traffic between nodes is unencrypted. On untrusted networks you need TLS.

Erlang can tunnel all inter-node traffic over TLS using the inet_tls_dist module, configured via a proto_dist flag and a certificate file.

The config file points to your certificate, key, and CA so nodes mutually authenticate and encrypt.

The Erlang Port Mapper Daemon (epmd) registers node ports. Never expose epmd or distribution ports to the public internet; firewall them or use a VPN.

A node started with -hidden connects without joining the global mesh, useful for tools that should not be part of the cluster's full-trust topology.

For safe distribution:

• Use a strong, unique cookie
• Protect the cookie file (chmod 400)
• Enable TLS on untrusted networks
• Firewall epmd and distribution ports

You learned to secure distributed Erlang.

• Matching cookies authenticate nodes
• Protect the .erlang.cookie file
• Use TLS distribution for encryption
• Firewall epmd and distribution ports