Contents
1.Creation of public and private key pairs
Create a public/private key pair for a user connecting to a Linux server using OpenSSH.
Use ssh-keygen to create the key pair.
The creation of a public/private key pair is performed with the authority of the user logging in remotely.
If you do not specify the creation destination and file name, id_ed25519 and id_ed25519.pub will be created in /home/(user name)/.ssh/. On the way, also enter the password for the key.
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# su - huong [huong@Lepard~]$ ssh-keygen -t ed25519 Generating public/private ed25519 key pair. Enter file in which to save the key (/home/huong/.ssh/id_ed25519): [Enter] Created directory '/home/huong/.ssh'. Enter passphrase (empty for no passphrase): [Password] Enter same passphrase again: [Again Password] Your identification has been saved in /home/huong/.ssh/id_ed25519 Your public key has been saved in /home/huong/.ssh/id_ed25519.pub The key fingerprint is: SHA256:caoCOTvdXeazCAthGIYGNHLppvbtC9Ot7MfTN8cAB08 huong@Lepard The key's randomart image is: +--[ED25519 256]--+ |+o.. | |ooo . E | |.oo . = | |..o+ = o | | o= o S = | |.. *.o.o + . | |. +o=.=.o o o | | o++.* o = o | | o*+ o o o | +----[SHA256]-----+ |
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$ cat ~/.ssh/id_ed25519.pub >> ~/.ssh/authorized_keys $ chmod 600 ~/.ssh/authorized_keys $ chmod 700 ~/.ssh/ |
Save the created private key id_ed25519 to an appropriate location on windows using winSCP.
Start Winscp and click "New Session"
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Host name : Server IP Address
Port number : SSH port number
User name : General username
Password : General username Password
「Save」
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Site name : Any connection name
Click "OK"
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After confirming the server, click "Login".
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Click "Update" when the following screen appears
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In the following screen, enter the user's password in the "Pasword" field.
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When connected, the right column is the server side and the left column is the PC (Windows) side.
Save the file "id_ed25519" in the .ssh directory to an appropriate location on Windows in the left column.
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2.Editing SSH Configuration File
Edit the SSH configuration file to disable password authentication.
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# vi /etc/ssh/sshd_config # Line 66 : Uncommented and changed to password authentication disabled. PasswordAuthentication no # systemctl restart sshd |
How to connect with Tera Term
Start Tera Term, and select "File" menu "New connection"
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Host : Server IP Address
TCP port : SSH Port
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If you get the following security warning "Replace…. and click "Continue".
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User name : Login User Name
Password :Password specified in the creation of a public/private key pair
Under "Use RSA/DSA/ECDSA/ED25519 key to log in", set "Private key file:" to "id_ed25519" that you just saved in Windows.
Set "id_ed25519" that you just saved in Windows to "Private key file:" and click "OK".
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3.Creating a private key using PuTTYgen
Start Winscp, select the appropriate server, and launch Run PuTTYgen from Tools.
Select the appropriate server
Click "Load"
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[ Open File Dialog ], change the file type to [ All Files (. Change the file type to [ All Files (. *) ] and load the private key id_ed25519 transferred from the Linux server.
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Enter the passphrase you entered when you created the private key on the server side
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Click the [ Save private key ] button to save the private key.
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Here we save it as id_ed25519.ppk (in Windows).
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Select the appropriate server and click "Edit"
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Click on "Advanced"
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Open the "Authentication" menu and specify "id_ed25519.ppk" saved in Windows for "Private key file"
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Click "Save"
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Click on "Login"
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The password is the password set in "Creating a public and private key pair" above
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When connecting with Tera Term
In the "Use RSA/DSA/ECDSA/…" field.
Specify "id_ed25519.ppk" saved in windows