在linux下用rsh实现两个节点的无密码互通

     由于要做并行计算，现在要把机器配置成两台无密码可以互相访问。现在来说说具体配置rsh的流程。

机器配置：64位机，4核，X86服务器主机，装centos 4.8 64位操作系统。网络互通采用infiniband网卡通信。

1、检查有无安装rsh-server包
[root@node1 ~]# rpm -qa rsh-server

若没有安装，则可以通过下面的命令来安装。

2、 安装rsh-server包

[root@node1]# yum search rsh-server

    找到一个rsh-server.x86_64,通过下面的命令安装。

[root@node1]# yum install rsh-server.x86_64

直到安装完毕。

3、修改cd /etc/xinetd.d/目录下的rlogin，将disable= yes改为disable= no
[root@node1 ]# vi /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
}

4、同样修改cd /etc/xinetd.d/目录下的rsh，将disable= yes改为disable= no
[root@racnode1 package]# vi /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
}

再到/etc/pam.d/目录下,把rsh文件中的auth required /lib/security/pam_securetty.so

5、重启xinetd服务
[root@node1]# service xinetd restart
Stopping xinetd: [ OK ]
Starting xinetd: [ OK ]

6、重启xinetd服务
将rexec、rlogin、rsh加入到/etc/securetty
[root@node1 ~]# echo "rexec" >> /etc/securetty
[root@node1 ~]# echo "rlogin" >> /etc/securetty
[root@node1 ~]# echo "rsh" >> /etc/securetty

7、配置rsh server

修改/etc/securetty文件: echo rsh >>/etc/securetty

如果打算用root作为rsh用户的话:

先用root登录到机器A中进行以下操作: (.rhosts 在/root/目录下)

[root@node1]#  echo "192.168.1.221 root" >>.rhosts   //允许192.168.0.221 以root访问

[root@node1]#  echo "192.168.1.222 root" >>.rhosts    

重启rsh server.

.rhosts一般位于 rsh server服务器相对应账号目录下比如root(与.bash_profile在同一目录)

查看是否配置成功：

[root@node1]# more .rhosts

192.168.1.221 root

192.168.1.222 root

8、配置vi /etc/hosts，加入对方的IP和机器名(hostname)。机器名可以参考127.0.0.1一行。

[root@node1]# vi /etc/hosts

# Do not remove the following line, or various programs

# that require network functionality will fail.

127.0.0.1              localhost.localdomain localhost

192.168.1.221          node1

192.168.1.222          node2

9、vi /etc/hosts.env和 /etc/hosts.allow里分别写入

node1 换行node2

10、重启rsh server.

[root@node1]# service xinetd restart

Stopping xinetd: [  OK  ]

Starting xinetd: [  OK  ]

测试：最后在其中的一台机器上输入命令：rsh node1或者 rsh  node2可以不用密码就可以和另外一台主机通信。

提示有如下警告信息：

#rsh node2
connect to address 192.168.1.**: Connection refused

Trying krb4 rlogin...

connect to address 192.168.1.**: Connection refused

trying normal rlogin (/usr/bin/rlogin)

Last login: Thu May 23 22:32:15 from 192.168.1.**

通过下面这条命令可以把警告命令给去掉。

 rpm -e krb5-workstation