While installing and configuring Oracle Cluster you need to configure RSH Server (Quite outdated but still oracle requires it). Today in this post I will explain how you can configure RSH on nodes which are going to be clustered.

1) Installation of RSH:-
You can install RSH using YUM or RPM package manager.

For YUM execute following command from Shell (as root)

yum install rsh-server

For RPM:-
Download rsh-server RPM from Repository OR mount your RHEL DVD and go to RPM’s Directory and execute following command:-

rpm -ivh rsh-server-0.17-40.el5.x86_64.rpm

2) Enable RSH Service.

By default RSH service is disabled to enable it open and Edit /etc/xinetd.d/rsh and /etc/xinetd.d/rlogin ; find term “disable”. Change “yes” to “no”. Make sure that both the files looks like following

[root@rac1 ]# cat /etc/xinetd.d/rsh
# default: on
# description: The rshd server is the server for the rcmd(3) routine and, \
# consequently, for the rsh(1) program. The server provides \
# remote execution facilities with authentication based on \
# privileged port numbers from trusted hosts.
service shell
{
socket_type = stream
wait = no
user = root
log_on_success += USERID
log_on_failure += USERID
server = /usr/sbin/in.rshd
disable = no
}

_

[root@rac1 ]# cat /etc/xinetd.d/rlogin
# default: on
# description: rlogind is the server for the rlogin(1) program. The server \
# provides a remote login facility with authentication based on \
# privileged port numbers from trusted hosts.
service login
{
socket_type = stream
wait = no
user = root
log_on_success += USERID
log_on_failure += USERID
server = /usr/sbin/in.rlogind
disable = no
}

3) Restart the Service on all node’s.

Restart xinetd service on all clustered nodes and also make sure to enable it on reboot. These operations can be done using following commands.

/etc/init.d/xinetd restart
chkconfig rsh on
chkconfig rlogin on

4) Without Password logins

For Oracle Cluster setup its important that you should able to login into any other node without entering passwords. In SSH you can do that by setting SSH Keys but in RSH all you have to create /etc/hosts.equiv and insert all the Nodes in that. Following are the commands

touch /etc/hosts.equiv
chmod 600 /etc/hosts.equiv
chown root:root /etc/hosts.equiv

Then allow oracle user to connect servers without password. Insert following in /etc/hosts.equiv file

+rac1 oracle
+rac2 oracle
+pvt1 oracle
+pvt2 oracle

Here, rac1, rac2, pvt1 and pvt2 are the servers in cluster (rac is public IP and pvt is private IP).

Thats it, now try to connect servers using command “rlogin [serverip]”.