ssh 免密码登录

1、使用 ssh-keygen -t  rsa 生成私钥和公钥

ssh-keygen -b 1024 -t dsa

Generating public/private dsa key pair.
Enter file in which to save the key (/home/user/.ssh/id_dsa): /home/user/.ssh/id_dsa
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/user/.ssh/id_rsa.
Your public key has been saved in /home/user/.ssh/id_ras.pub.

 

2、密钥分发
把私钥放在自己的机器上的~/.ssh/目录下并保证访问权限是“-rw-------”(即600)。
再把生成的公钥放在要连接的远程主机的~/.ssh/目录下并改名为authorized_keys,并且保证文件除了属主外没有被人修改的权限。

命令
cd ~/.ssh

ssh-copy-id user@IP
or
ssh-copy-id –i id_rsa.pub user@IP

3、登录
ssh username@ip直接登录

4、运行命令
ssh user@ip  ./test.sh

 

普通用户ssh连接linux服务器是总是提示：

ulimit: open files: cannot modify limit: Operation not permitted

解决办法：
vi /etc/security/limits.conf

添加：

* soft nofile 65535
* hard nofile 65535

如果无法登录，
删除/home/user/.ssh/known_hosts文件再试