The Answer Guy 35: Remote Login as 'root'
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Remote Login as 'root'
From Crown Magnetics, Inc on Fri, 20 Nov 1998
How can I find out how to make it possible on A Linux system to
login as root at a location other than the console?
(I'm used to Solaris Intel and there it's in
/etc/default/login) but I'm not sure how to do this
in Linux . . .
Thanks - Sheldon
Most UNIX systems refuse to allow remote users (telnet)
to login directly as root. This is intended to
require that you login under your normal account and
'su' to 'root' as necessary.
Overall I think this is an excellent policy to enforce.
Actually I think its still far too liberal. You really
should consider installing 'ssh', STEL, or a similar
secure and encrypted remote access system.
If you really insist on being able to do this via
'telnet' or 'rlogin' then you'll have to look in
your man pages for the 'telnetd', 'login' and 'in.rlogind'
(or equivalent) programs. I'm not saying this to be
churlish --- there are different suites of these utilities
that are included with different distributions.
Some distributions use the "Shadow Suite" (originally by
J. Haugh III?). There is a file called '/etc/login.defs'
(with a corresponding man page: login.defs(5)). That
case a CONSOLE directive/option. Read about it. Red Hat
includes the PAM suite of these utilities. It's possible
to remove the 'securetty' check from the specific PAM
service configuration files by editing the files under the
/etc/pam.d/ directory (more recent versions) or the
one /etc/pamd.conf file (obsolete).
In some cases you may have to edit your /etc/inetd.conf file
to add or remove options from the 'in.*' services listed
therein. For example you have to add a -h to the
in.rlogind entry if you want to force that command to
respect a '.rhosts' file for the 'root' user. That man
page notes that these flags are not used if PAM is
enabled --- and directs you do use the /etc/pam.d/
configuration files instead.
Those couple of cases should handle the vast majority
of Linux distributions. I realize that my answer is
basically RTFM --- but I hope I've directed you to the
appropriate FM's to R.
Copyright © 1998, James T. Dennis
Published in The Linux Gazette Issue 35 December 1998