How to remove the password prompt when using the remote Copy command scp in linux

How to remove the password prompt when using the remote Copy command scp in linux-Linux Enterprise Application-Linux server application information. The following is a detailed description. Author: Novels

After searching for the Internet for half a day, it is not simple and clear. I will summarize the following:

Write the ssh public key file of your local host user to the remote host user ~ /. Ssh/authorized_keys file, the specific method

Assume that the local host and remote host

1. users in the localhost host

Run ssh-keygen-t rsa

The result is as follows:

Generating public/private rsa key pair.

Enter file in which to save the key (/home/. username/ssh/id_rsa): # Press Enter

Enter passphrase (empty for no passphrase): # Press Enter

Enter same passphrase again: # Press Enter

Your identification has been saved in/home/. username/. ssh/id_rsa.

Your public key has been saved in/home/. username/. ssh/id_rsa.pub.

The key fingerprint is:

38: 25: c1: 4d: 5d: d3: 89: bb: 46: 67: bf: 52: af: c3: 17: 0c username @ localhost

Generating RSA keys:

Key generation complete.

Will be in the user directory ~ /. Ssh/generate two files: id_rsa, id_rsa.pub

The procedure is as follows:

Ssh-keygen-t rsa or ssh-keygen-d (dsa) => Generate id_rsa, id_rsa.pub
Scp id_rsa.pub server_hostname :~ /. Ssh/
Ssh server_hostname
Cat. ssh/id_rsa.pub>. ssh/authorized_keys (append)

In this way, you can log on with key authentication without entering a password.

2. Copy the id_rsa.pub file to the remote host's user directory.

Cat id_rsa.pub >> ~ /. Ssh/authorized_keys

You can.

In this way, users of the localhost can log on to the remote host through ssh without a password.

The following errors are often found during testing:

@ WARNING: remote host identification has changed! @

It is possible that someone is doing something nasty!
Someone cocould be eavesdropping on you right now (man-in-the-middle attack )!
It is also possible that the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
1f: a3: 2b: b5: 27: 0c: 5c: 7b: 89: 27: ff: AB: cd: ba: 31: 66.
Please contact your system administrator.
Add correct host key in/root/. ssh/known_hosts to get rid of this message.
Offending key in/root/. ssh/known_hosts: 6
RSA host key for 60.28.15.234 has changed and you have requested strict checking.
Host key verification failed.

The solution is to delete the known_hosts file.

3. Enter passphrase (empty for no passphrase ):

Enter is skipped. password will not be asked next time.

Briefly describe:

Id_rsa: private key
Id_rsa.pub: public key

Copy the public key (id_rsa.pub) to the remote computer and add it to. ssh/authorized_keys of the user.

After the connection is established, the private key (id_rsa) of the local machine and the public key (authorized_keys) of the remote computer are used for authentication. After confirmation, you can log on directly without entering the account password, it is also safe.