如何配置ssh服务使得不用输入账号密码即可连接远程主机

# 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:

SHA256:GCyx2cSYE6yR7xCuUVOF0Omvp5fEoxv0Y2wOQvMRB98 root@lijia

The key's randomart image is:

+---[RSA 2048]----+

|  .*=Oo          |

|  * OX..         |

| o B=.* E        |

|. + o+ o         |

| ooooo. S        |

|.. +.+=          |

|  . ++*o         |

|   .o*+.         |

|    o=.          |

+----[SHA256]-----+

# ssh-copy-id root@121.***.***.64

/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"

/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed

/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys

root@121.196.12.64's password:

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'root@121.***.***.64'"

and check to make sure that only the key(s) you wanted were added.

# ssh root@121.196.12.64

Welcome to Alibaba Cloud Elastic Compute Service !

Activate the web console with: systemctl enable --now cockpit.socket

Last login: Fri Nov 20 10:28:37 2020 from 111.38.123.86

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