rlogin

Additional Notes

rlogin is a legacy remote login command that establishes a terminal session on a remote host. It was part of the r-utilities (rlogin, rsh, rcp, rexec) developed at Berkeley for Unix systems.

Authentication relies on host-based trust via /etc/hosts.equiv or per-user .rhosts files, with all traffic transmitted in cleartext. This makes it entirely unsuitable for untrusted networks. The protocol is superseded by SSH for all modern use cases.

Syntax

rlogin [-8EKLdx] [-e char] [-l username] host

Parameters

• host: The remote hostname or IP address to connect to.

Common Options

• -l username: Log in as a specific user on the remote host.
• -8: Allow eight-bit input data.
• -d: Enable socket-level debugging.
• -E: Do not use any character as the escape character.
• -e char: Set the escape character (default is ~).
• -K: Disable Kerberos authentication.
• -L: Allow the session to be run without a controlling terminal.
• -x: Enable DES encryption (if supported).

Examples

rlogin -l alice server.example.com

Log in to server.example.com as user alice.

rlogin backup-server

Log in to backup-server using the current local username.

Practical Notes

• rlogin is obsolete. Use ssh for all remote logins.
• Host-based trust authentication is a major security risk.
• The rlogin protocol uses TCP port 513.
• Most modern distributions no longer include an rlogind server.