If you are trying to connect to a server through a socket, then you are referring to the following commands:
- The /server command itself is /sockopen <address> <port>. When the socket opens, you send 2 or three commands to register yourself as a user on that server (depending on whether or not you need to use a password for that port or not).
- [PASS <password for that port>]
- NICK <primary nick>
- USER <userid> <email host> <"IP"> :<Real name/Fullname/GCOS>
If you are referring to connecting one server to another server, that is dependent on the IRCd that you are using, but most of the IRCds that I know of use
/.raw CONNECT <server> [<port> [<hub>]]. Do not use that command unless you are very sure you know what you are doing and why.