[root@izwz97s23bov6qmem6poj8z ~]# useradd jundong
[root@izwz97s23bov6qmem6poj8z ~]# passwd jundong
New password:
Retype new password:
passwd: all authentication tokens updated successfully.

[root@node1 ~]# ssh-keygen
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:W05lCKLqZ8FWTyAwTsUrBzg7HRzZfZ8ZbacHg/Wnf6c root@node1
The key's randomart image is:
+---[RSA 2048]----+
| o=Bo.o .  +.    |
|oo=.oo.o..o.=..  |
| +.o.......=o=. .|
|o ooo. o  +o. .o |
| ..o+   S o  ..  |
| . . .   =     . |
|  . o   . .     +|
|   o           .o|
|              E  |
+----[SHA256]-----+

ssh-copy-id jundong@120.78.150.47

[root@node1 ~]# ssh-copy-id jundong@120.78.150.47
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '120.78.150.47 (120.78.150.47)' can't be established.
ECDSA key fingerprint is SHA256:KwfKwzN4xqw7/VxoVw5IoTi0NhUPZ+h2fSQXi3zgXXY.
ECDSA key fingerprint is MD5:22:b0:8e:c0:21:e6:96:b1:de:bd:bd:c4:08:d9:bf:4d.
Are you sure you want to continue connecting (yes/no)? yes
/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
jundong@120.78.150.47's password:

Number of key(s) added: 1Now try logging into the machine, with:   "ssh 'jundong@120.78.150.47'"
and check to make sure that only the key(s) you wanted were added.

[root@node1 ~]# ssh jundong@120.78.150.47Welcome to Alibaba Cloud Elastic Compute Service ![jundong@izwz97s23bov6qmem6poj8z ~]$