Configuring rlogin remsh rcp to not request login password
Contents
Abstract
The main purpose of this article is to clarify that [r]commands (remsh, rlogin, rcp) requires either the source FQDN or it's an alias on the same domain of the destiny server on the /etc/hosts file of the destiny server. How the source clients resolve the destiny (IP, FQDN, alias) of themself or the target server is of no consecuence.
The Operating Environment (11.11, 11.23 or 11.31) plays no different in the problem. If you found that this behaivor is consistent across the systems, review steps by step to determina how hostname resolution is performed on the server, that is frequently the source of all issues with remsh.
Test Enviroment
The three servers are configure to resolve host using /etc/hosts file.
FQDN alias OS.Rev. IP Address Function =============================================================== cobble.alf.cpqcorp.net cobble 11.11 16.113.011.181 Target jets.rose.hp.com jets 11.11 15.043.235.193 Source delta.cri.hp.com delta 11.31 16.090.048.075 Source
Using the correct FQDN
-> /etc/hosts 127.0.0.1 localhost loopback 16.113.11.181 cobble.alf.cpqcorp.net cobble 15.43.235.193 jets.rose.hp.com jets 16.90.48.75 delta.cri.hp.com delta #15.43.235.193 jets.alf.cpqcorp.net jets #16.90.48.75 delta.alf.cpqcorp.net delta
-> $HOME/.rhosts delta.cri.hp.com root jets.rose.hp.com root #jets root #delta root
delta: / # rlogin cobble jets: / # rlogin cobble
This configuration works correctly. Neither rlogin or remsh request use password from jets and delta. The source client is resolve to the FQDN on cobble /etc/hosts file.
cobble: / # who -R root pts/0 Aug 4 13:11 (jets.rose.hp.com) root pts/1 Aug 4 13:12 (delta.cri.hp.com)
Using alias without changing FQDN entries
-> /etc/hosts 127.0.0.1 localhost loopback 16.113.11.181 cobble.alf.cpqcorp.net cobble 15.43.235.193 jets.rose.hp.com jets 16.90.48.75 delta.cri.hp.com delta #15.43.235.193 jets.alf.cpqcorp.net jets #16.90.48.75 delta.alf.cpqcorp.net delta
-> $HOME/.rhosts #delta.cri.hp.com root #jets.rose.hp.com root jets root delta root
delta: / # rlogin cobble jets: / # rlogin cobble
This configuration doesn't work correctly. Either rlogin and remsh request request password from jets and delta. The source client is resolve to their correct FQDN (rose.hp.com & cri.hp.com) on cobble /etc/host file.
cobble: / # who -R root pts/0 Aug 4 13:29 (jets.rose.hp.com) root pts/1 Aug 4 13:29 (delta.cri.hp.com)
Using alias changing FQDN entries
-> /etc/hosts 127.0.0.1 localhost loopback 16.113.11.181 cobble.alf.cpqcorp.net cobble #15.43.235.193 jets.rose.hp.com jets #16.90.48.75 delta.cri.hp.com delta 15.43.235.193 jets.alf.cpqcorp.net jets 16.90.48.75 delta.alf.cpqcorp.net delta
-> $HOME/.rhosts #delta.cri.hp.com root #jets.rose.hp.com root jets root delta root
delta: / # rlogin cobble jets: / # rlogin cobble
This configuration works correctly. Neither rlogin or remsh request password from jets and delta. The source client hostname is resolved to the "false" FQDN (alf.cpqcorp.net) on cobble /etc/host file.
cobble: / # who -R root pts/0 Aug 4 13:36 (jets.alf.cpqcorp.net) root pts/1 Aug 4 13:36 (delta.alf.cpqcorp.net)