.\" Copyright (c) 1995 Peter Tobias .\" This file may be distributed under the GNU General Public License. .TH HOSTS.EQUIV 5 2003-08-24 "Linux" "Linux Programmer's Manual" .SH NAME /etc/hosts.equiv \- list of hosts and users that are granted "trusted" \fBr\fP command access to your system .SH DESCRIPTION The \fBhosts.equiv\fP file allows or denies hosts and users to use the \fBr\fP-commands (e.g., \fBrlogin\fP, \fBrsh\fP or \fBrcp\fP) without supplying a password. .PP The file uses the following format: .TP \fI[ + | \- ]\fP \fI[hostname]\fP \fI[username]\fP .PP The \fIhostname\fP is the name of a host which is logically equivalent to the local host. Users logged into that host are allowed to access like-named user accounts on the local host without supplying a password. The \fIhostname\fP may be (optionally) preceded by a plus (+) sign. If the plus sign is used alone it allows any host to access your system. You can explicitly deny access to a host by preceding the \fIhostname\fP by a minus (\-) sign. Users from that host must always supply a password. For security reasons you should always use the FQDN of the hostname and not the short hostname. .PP The \fIusername\fP entry grants a specific user access to all user accounts (except root) without supplying a password. That means the user is NOT restricted to like-named accounts. The \fIusername\fP may be (optionally) preceded by a plus (+) sign. You can also explicitly deny access to a specific user by preceding the \fIusername\fP with a minus (\-) sign. This says that the user is not trusted no matter what other entries for that host exist. .PP Netgroups can be specified by preceding the netgroup by an @ sign. .PP Be extremely careful when using the plus (+) sign. A simple typographical error could result in a standalone plus sign. A standalone plus sign is a wildcard character that means "any host"! .SH FILES .I /etc/hosts.equiv .SH NOTES Some systems will only honor the contents of this file when it has owner root and no write permission for anybody else. Some exceptionally paranoid systems even require that there be no other hard links to the file. .PP Modern systems use the Pluggable Authentication Modules library (PAM). With PAM a standalone plus sign is only considered a wildcard character which means "any host" when the word .I promiscuous is added to the auth component line in your PAM file for the particular service .RB "(e.g., " rlogin ). .SH "SEE ALSO" .BR rhosts (5), .BR rlogind (8), .BR rshd (8) .SH COLOPHON This page is part of release 3.44 of the Linux .I man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.