pam_rhosts — The rhosts PAM module



This module performs the standard network authentication for services, as used by traditional implementations of rlogin and rsh etc.

The authentication mechanism of this module is based on the contents of two files; /etc/hosts.equiv (or and ~/.rhosts. Firstly, hosts listed in the former file are treated as equivalent to the localhost. Secondly, entries in the user's own copy of the latter file is used to map "remote-host remote-user" pairs to that user's account on the current host. Access is granted to the user if their host is present in /etc/hosts.equiv and their remote account is identical to their local one, or if their remote account has an entry in their personal configuration file.

The module authenticates a remote user (internally specified by the item PAM_RUSER connecting from the remote host (internally specified by the item PAM_RHOST). Accordingly, for applications to be compatible this authentication module they must set these items prior to calling pam_authenticate(). The module is not capable of independently probing the network connection for such information.



Print debug information.


Don't print informative messages.


Handle account as root.

Module Types Provided

Only the auth module type is provided.

Return Values


The remote host, remote user name or the local user name couldn't be determined or access was denied by .rhosts file.


User is not known to system.


To grant a remote user access by /etc/hosts.equiv or .rhosts for rsh add the following lines to /etc/pam.d/rsh:

auth     required
auth     required
auth     required
auth     required

See Also

rootok(3), hosts.equiv(5), rhosts(5), pam.conf(5), pam.d(5), pam(8)


pam_rhosts was written by Thorsten Kukuk <>


05/18/2017 Linux-PAM Manual