Contents
Create 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.
This time, we will create a key set using the RSA cipher used in the SSH protocol Version 2.
The creation of a public/private key pair is performed with remote login user privileges (e.g., huong).
If you do not specify the destination and file name, id_ed25519 and id_ed25519.pub will be created in /home/huong/.ssh/. On the way, 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): Created directory '/home/huong/.ssh'. Enter passphrase (empty for no passphrase): Enter same passphrase again: 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:KZJJgogFABx2SzuxPzEpFaTwphsmeHiv31fLrnJV6NU huong@Lepard The key's randomart image is: +--[ED25519 256]--+ |B=o+.+. | |++= B . | |+ .X.+ . . | |..oo+oo .. o E | |++o +o. S. o | |ooo. ... + | | . . + . | | . .. o o | | ... .+.o. | +----[SHA256]-----+ |
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$ chmod 700 ~/.ssh $ cat ~/.ssh/id_ed25519.pub >> ~/.ssh/authorized_keys $ chmod 600 ~/.ssh/authorized_keys |
Use Winscp or other means to save the private key (~/.ssh/id_ed25519) in an appropriate location on Windows.
Start Winscp
Host name : Server IP Address
Port number : SSH Port
User name : Server Login User
Password : Password for the same user
「Save」
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Site name : Name the connection with any name.
Click "OK"
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Click "Login" to return to the following screen.
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If the following screen appears, click "Update".
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In the following screen, enter the user's password in the "Pasword" field.
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When connected, the left column is the server side and the right column is the PC (Windows) side.
Save the file “id_ed25519” in the .ssh directory to a suitable location on Windows in the right column.
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Change to log in only with private key
Edit the SSH configuration file to disable password authentication.
su - to become root.
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$ su - Password: # vi /etc/ssh/sshd_config # Per Line 58 #PasswordAuthentication yes ← Uncomment by deleting # at the beginning of the line and change to the following 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 number
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If you get the following security warning "Replace.... "check the box and "Continue".
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User name : Login username
Password :Password specified in the creation of a public/private key pair
Check the "Use RSA/DSA...." checkbox. and in the "Private key file" field, specify the "id_ed25519" that you just saved in windows.
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Creating a private key using PuTTYgen
Start Winscp and launch "Run Puttygen" from "Tools".
Select the appropriate server
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Click Load
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The [ Open File Dialog ] will open, 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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Save it here 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
"Use RSA/DSA/ECDSA/…"
Specify "id_ed25519.ppk" saved in windows
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