ssh-copy-id command in Linux
The Linux ssh-copy-id command simplifies the process of copying SSH keys to remote servers, allowing for secure and efficient access without the need for manual key management. By using ssh-copy-id, users can quickly and easily authorize their public keys on remote servers, streamlining the authentication process and enhancing overall security.
ssh-copy-id Syntax:
ssh-copy-id [options] [user@]hostname
Linux ssh-copy-id Options:
Option | Description |
---|---|
-i | Identity file |
-f | Force mode (overwrite keys) |
-n | Dry run (do not make any changes) |
-h | Show help |
-o | Additional options |
-p | Port number |
ssh-copy-id Parameters:
Parameter | Description |
---|---|
[options] | Specify the options for the ssh-copy-id command |
[user] | Username for the SSH connection |
[hostname] | The target host to copy the SSH key to |
How to use ssh-copy-id command:
Copy SSH key to a remote server
ssh-copy-id user@remote_host
Copies the SSH key of the local user to the specified remote host.
Specify a non-default SSH port
ssh-copy-id "-p 2222 user@remote_host"
Copies the SSH key while specifying a non-default SSH port (in this case, port 2222) for the remote host.
Interactive mode for confirmation
ssh-copy-id -i user@remote_host
Prompts for confirmation in interactive mode before adding the SSH key to the remote host.
Copy SSH key using a specific identity file
ssh-copy-id -i ~/.ssh/another_key user@remote_host
Copies the SSH key specified by the identity file parameter to the remote host.
Disable password authentication during key copy
ssh-copy-id -n user@remote_host
Disables password authentication temporarily during the key copy process for increased security.
Specify a custom path for the authorized keys file
ssh-copy-id "-f ~/.ssh/custom_authorized_keys user@remote_host"
Copies the SSH key to the remote host while using a custom path for the authorized keys file.
Preserve remote key in the known_hosts file
ssh-copy-id "-o 'UserKnownHostsFile=~/.ssh/known_hosts' user@remote_host"
Preserves the remote host key in the known_hosts file, which is useful for keeping track of verified host keys.
Override the SSH configuration
ssh-copy-id "-F /etc/ssh/ssh_config user@remote_host"
Copies the SSH key to the remote host using a specified SSH configuration file for custom settings.
How do I use ssh-copy-id in bash?
To use the ssh-copy-id command in Linux, execute the following command:
ssh-copy-id user@hostname
How to copy the SSH key to a specific port using ssh-copy-id?
To copy your SSH key to a specific port on a remote host with ssh-copy-id, use the following command:
ssh-copy-id -p port user@hostname
How can I specify a custom SSH key file using ssh-copy-id?
To specify a custom SSH key file when using ssh-copy-id, you can use the following command:
ssh-copy-id -i /path/to/key user@hostname
How do I disable strict host key checking when using ssh-copy-id?
To disable strict host key checking and automatically add the host key when using ssh-copy-id, you can use the following command:
ssh-copy-id -o StrictHostKeyChecking=no user@hostname
How to prompt for the user’s password on the remote system when using ssh-copy-id?
To prompt for the user’s password on the remote system when using ssh-copy-id, you can use the following command:
ssh-copy-id -o PubkeyAuthentication=no user@hostname
How to copy a specific SSH key to a remote host using ssh-copy-id?
To copy a specific SSH key to a remote host with ssh-copy-id, use the following command:
ssh-copy-id -i /path/to/key user@hostname
How do I provide a custom port and user when using ssh-copy-id?
To specify both a custom port and user when using ssh-copy-id, you can use the following command:
ssh-copy-id -p port user@hostname
How do I add a comment when copying an SSH key with ssh-copy-id?
To add a comment when copying an SSH key using ssh-copy-id, you can use the following command:
ssh-copy-id -C "user@hostname key" user@hostname
How do I force the SSH key copy operation using ssh-copy-id?
To force the SSH key copy operation and overwrite any existing keys on the remote host, you can use the following command:
ssh-copy-id -f user@hostname
Applications of the ssh-copy-id command
- Securely copy the public key to a remote server for passwordless authentication
- Automate the process of adding the public key to the authorized_keys file on a remote server