1：安装JDK 下载好jdk-7u45-linux-x.gz 或从其它电脑copy过去 [jifeng@feng01 ~]$scp -r ./jdk-7u45-linux-x.gz jifeng@jifeng01:/home/jifengThe authenticity of host jifeng01 (10.3.7.214) cant be established.RSA key fingerprint is a8:9d:34:63:

1：安装JDK

下载好jdk-7u45-linux-x.gz

或从其它电脑copy过去

[jifeng@feng01 ~]$scp -r ./jdk-7u45-linux-x.gz jifeng@jifeng01:/home/jifeng
The authenticity of host 'jifeng01 (10.3.7.214)' can't be established.
RSA key fingerprint is a8:9d:34:63:fa:c2:47:4f:81:10:94:fa:4b:ba:08:55.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'jifeng01,10.3.7.214' (RSA) to the list of known hosts.
jifeng@jifeng01's password: 
jdk-7u45-linux-x.gz 100% 132MB 32.9MB/s 00:04 

解压:tar vzxf jdk-7u45-linux-x.gz

然后在/home/jifeng/.bash_profile文件末加上以下语句：

export JAVA_HOME=$HOME/jdk1.7.0_45

export PATH=$JAVA_HOME/bin:$PATH

export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar

接着使文件生效：source /home/jifeng/.bash_profile

最后，验证是否安装成功：

java -version

[jifeng@jifeng01 ~]$ source /home/jifeng/.bash_profile
[jifeng@jifeng01 ~]$ java -version
java version "1.7.0_45"
Java(TM) SE Runtime Environment (build 1.7.0_45-b18)
Java HotSpot(TM) -Bit Server VM (build 24.45-b08, mixed mode)
[jifeng@jifeng01 ~]$ 

[jifeng@jifeng01 ~]$ ssh-keygen -t -rsa
unknown key type -rsa
[jifeng@jifeng01 ~]$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/jifeng/.ssh/id_rsa): 
/home/jifeng/.ssh/id_rsa already exists. 存在文件要覆盖
Overwrite (y/n)? y
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/jifeng/.ssh/id_rsa.
Your public key has been saved in /home/jifeng/.ssh/id_rsa.pub.
The key fingerprint is:
b0:f3:f7:6f:80:98:09:48:52:03:2e:a5:d3:e6:b1:a8 jifeng@jifeng01

[jifeng@jifeng01 ~]$ cd .ssh
[jifeng@jifeng01 .ssh]$ ls
authorized_keys id_rsa id_rsa.pub
[jifeng@jifeng01 .ssh]$ ls -l
总计 12
-rw-r--r-- 1 jifeng jifeng 397 07-22 15:40 authorized_keys
-rw------- 1 jifeng jifeng 1675 07-23 22:56 id_rsa
-rw-r--r-- 1 jifeng jifeng 397 07-23 22:56 id_rsa.pub

[jifeng@jifeng02 ~]$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/jifeng/.ssh/id_rsa): 
/home/jifeng/.ssh/id_rsa already exists.
Overwrite (y/n)? y
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/jifeng/.ssh/id_rsa.
Your public key has been saved in /home/jifeng/.ssh/id_rsa.pub.
The key fingerprint is:
74:bb:ff:af:9d:f3:4e:2e:18:6b:91:45:ff:ac:37:85 jifeng@jifeng02
The key's randomart image is:
+--[ RSA 2048]----+
| |
| . |
| . . . . |
| . . . . .|
| S . o o.|
| .+ E +|
| . = .o|
| .+ o*o|
| ...oBX|
+-----------------+

[jifeng@jifeng01 .ssh]$ scp ./id_rsa.pub jifeng@jifeng02:/home/jifeng/.ssh/authorized_keys
The authenticity of host 'jifeng02 (10.3.7.212)' can't be established.
RSA key fingerprint is 5f:20:1a:77:96:99:4a:f2:5d:a1:1d:68:b6:91:5a:e7.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'jifeng02,10.3.7.212' (RSA) to the list of known hosts.
jifeng@jifeng02's password: 
id_rsa.pub 100% 397 0.4KB/s 00:00 
[jifeng@jifeng01 .ssh]$ 

[jifeng@jifeng01 .ssh]$ ssh jifeng02
Last login: Wed Jul 23 22:22:27 2014 from 10.254.254.8
[jifeng@jifeng02 ~]$