can not setup passwordless ssh using key by MANUALLY COPY public key to server

context:

firstly, i got a new ubuntu 20.04 server with a password
I’m using OpenSSH client on Windows 10
I want to do passwordless login, then I
- ssh to server using passwords,
- manually create ~/.ssh /authorized_keys and open it in vim
- copy&paste my public key content from my C:usersme.sshid_rsa.pub to ssh window.
- exit that ssh session and try to passwordless login,
- failed
(some more tries and many headbang)
I install Git Bash On Windows, then run ssh-copy-id and got another identical line in authorized_keys on the server
now I could successfully passwordless login to server

Why this happen? Does ssh-copy-id do more thing than just insert a line in (server) ~/.ssh/authorized_keys?

Asked By: Luke

Look at both entries in your .ssh/authorized_keys file. The first entry starts with sh-rsa, whereas your second starts with ssh-rsa. That’s most likely the problem. So when you copy/pasted your public key, you simply made a typo.

Answered By: mpboden