[root@localhost scripts]# ssh --help
usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]
[-D [bind_address:]port] [-e escape_char] [-F configfile]
[-i identity_file] [-L [bind_address:]port:host:hostport]
[-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]
[-R [bind_address:]port:host:hostport] [-S ctl_path]
[-W host:port] [-w local_tun[:remote_tun]]
[user@]hostname [command]1.查看ssh客户端的版本号
[test@ptestsrv1 ~]$ ssh -V OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
2. -l ：指定登陆的用户名
[test@ptestsrv1 ~]$ ssh -l root 192.168.0.70 [test@ptestsrv1 ~]$ ssh root@192.168.0.70 [test@ptestsrv1 ~]$ ssh 192.168.0.70 #没指定用户的情况下。默认使用客户端的用户，在这是test
3.-p port ：指定远程主机开放的sshd的服务的端口，默认是22
[test@ptestsrv1 ~]$ ssh root@192.168.0.70 22 [test@ptestsrv1 ~]$ ssh root@192.168.0.70 -p 22
ssh免密码登陆：
1.生成密钥 [root@jiang ~]# ssh-keygen -t rsa Generating public/private rsa key pair. Enter file in which to save the key (/root/.ssh/id_rsa): Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /root/.ssh/id_rsa. Your public key has been saved in /root/.ssh/id_rsa.pub. The key fingerprint is: 19:9e:20:ad:e4:4e:ac:dc:d9:1e:f7:cb:a9:a1:27:92 root@jiang The key's randomart p_w_picpath is: +--[ RSA 2048]----+ | | | . | | o o . | | + o o + | | = S | | . = o | | o +.o o | | E..+.+ . | | .oo..=. | +-----------------+ 2. [root@jiang ~]# ll /root/.ssh/ 总用量 16 -rw-r--r--. 1 root root 2366 4月 4 14:12 authorized_keys -rw-------. 1 root root 1675 4月 4 14:34 id_rsa #生成的私钥 -rw-r--r--. 1 root root 392 4月 4 14:34 id_rsa.pub#生成的公钥 -rw-r--r--. 1 root root 1186 4月 4 14:32 known_hosts 3. [root@jiang ~]# ssh-copy-id -i /root/.ssh/id_rsa.pub 192.168.56.101 #该指令会把生成的公钥添加到远程主机192.168.56.101的家目录 .ssh/authorized_keys 文件中。 root@192.168.56.101's password: Now try logging into the machine, with "ssh '192.168.56.101'", and check in: .ssh/authorized_keys to make sure we haven't added extra keys that you weren't expecting. 4. [root@jiang ~]# ssh 192.168.56.101 Last login: Fri Apr 4 14:34:47 2014 from 192.168.56.102 #不用密码登陆成功。
ssh免密码登陆设置时应注意的几个问题：
[root@zhu ~]# ll -d /root/ drwxr-xr-x. 11 root root 4096 4月 4 14:17 /root/ #远程主机家目录的权限一定要是755 [root@zhu .ssh]# ll /root/.ssh/ 总用量 16 -rw-------. 1 root root 392 4月 4 14:31 authorized_keys #该文件的权限一定要是600 -rw-------. 1 root root 1671 4月 4 13:34 id_rsa -rw-r--r--. 1 root root 390 4月 4 13:34 id_rsa.pub -rw-r--r--. 1 root root 396 4月 4 13:06 known_hosts
