Generate Keys Ssh Synoloy Nas

In order to provide a public key, each user in your system must generate one if they don’t already have one. This process is similar across all operating systems. First, you should check to make sure you don’t already have a key. By default, a user’s SSH keys are stored in that user’s /.ssh directory. You can easily check to see if you. Jul 09, 2019  Synology NAS DSM. When generating a CSR in Synology DSM, the Private Key is provided to you in a zip file on the last step. The key code is contained within a server.key file, that can be opened with a text editor, such as Notepad. Webmin works as a graphic user interface (GUI) on top of the command-line interface. Setting up SSH Access on your Synology. 2) Go to the Control Panel Advanced Mode Terminal & SNMP. 3) Click the Enable SSH Service option under the Terminal tab. NOTE: Synology restricts SSH/Telnet connections to members of the Administrators group on any particular Synology device.

  1. Generate Keys Ssh Synology Nas Pro
  2. Generate Keys Ssh Synology Nas Free
[Contents] [Index]

About This Document>>
Installing SSH Tectia Client >>
Getting Started >>
Connecting to a Remote Host
Defining Quick Connect Options
Generating Keys
Key Generation Wizard
Key Generation - Start
Key Generation - Key Properties
Key Generation - Generation
Key Generation - Enter Passphrase
Key Generation - Finish
Enrolling Certificates >>
Uploading Your Public Key >>
Using Public-Key Authentication with SSH Accession Lite >>
Examples of Use
Configuring SSH Tectia Client >>
Connecting to a Remote Host Computer>>
Transferring Files>>
Tunneling Applications>>
GUI Reference>>
Troubleshooting >>
Command-Line Tools >>

Generating Keys

If you are going to connect to a remote host computer using public-key authentication, you will have to generate a key pair before connecting.

Public-key authentication is based on the use of digital signatures. Each user creates a pair of key files. One of these key files is the user's public key, and the other is the user's private key. The server knows the user's public key, and only the user has the private key.

When the user tries to authenticate, the server checks for matching public keys and sends a challenge to the user end. The users are authenticated by signing the challenge using their private keys.

Remember that your private key file is used to authenticate you. Never expose your private keys. If anyone else can access your private key file, they can attempt to log in to the remote host computer as you, and claim to be you. Therefore it is extremely important that you keep your private key file in a secure place and make sure that no one else has access to it.

Do not use public-key authentication on a computer that is shared with other users. Generate keys only on your personal computer that no one else can access!

Also note that if you are using the Windows roaming profiles functionality, your personal settings will be replicated with the roaming profile server. If you store your private keys in the default location (under the profile folder of your Windows user account) your private keys may be susceptible to a malicious user listening to the network traffic. Therefore the User Settings folder should not be a directory that is used in profile roaming.

In order to use public-key authentication, you must first generate your own key pair. You can generate your own key files with the help of a built-in Key Generation wizard.

You can also import existing keys on the Keys page of the Settings dialog. See Section Managing Keys.

Key Generation Wizard

Key Generation - Start

Key Generation - Key Properties

Key Generation - Generation

Key Generation - Enter Passphrase

Key Generation - Finish

[Contents] [Index]

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Copyright © 2010 SSH Communications Security Corp.
This software is protected by international copyright laws. All rights reserved.
Copyright Notice

SSH is a cryptographic network protocol which is used to securely connect to a host over an unsecured connection. By default, any Linux operating system supports SSH; hence using a third party client is unnecessary like in the Windows platform. SSH protocol requires a server which accepts SSH connections, and a client which sends the requests to connect to the host. The typical usage of SSH protocol is remote login, remote commanding, and file transfer. Nowadays many Linux based servers make use of SSH protocol to tighten its security. A notable part of the SSH protocol is its authentication key pair which is used to identify and authorize users. So, this article demonstrates what are they, how to generate them, and how to utilize them to protect the server, and other relevant information.

SSH keys can serve as a means of identifying yourself to an SSH server using public-key cryptography and challenge-response authentication.The major advantage of key-based authentication is that in contrast to password authentication it is not prone to brute-force attacks and you do not expose valid credentials, if the server has been compromised.

How to Generate Keys and What Are They?

Generating SSH key pair consists of two basic phases. The first phase is generating the key pair on the local side, the second phase is copying it to the remote host, registering in the server and configuring the ssh daemon to make it useful. A key pair consists of two files, id_rsa and which are private and public keys respectively. The public key resides on the server side, whereas the private key is used when accessing it over SSH protocol.

In the following example ssh-keygen command is used to generate the key pair. When generating the key pair, the command prompt asks a name for a key, if it’s omitted the default name – id_rsa is used instead.

How to Use the Keys?


Once the key pair is generated on the local side through terminal window, the next step is to prepare them for employing for authentication purpose. The most convenient way to upload and register the public key in the server is using the ssh-copy-id command, what it does is copy the public key to the given user account located in the given host. As seen in the following example when the ssh-copy-id, username, the host name along with the password are all given the public key is copied and registered on the server side. If the username is root, the public key is uploaded to /root/.ssh/ on the server.

That being said, the server still isn’t protected with the SSH key pair as it’s not configured properly. Anyone can still access to the server if the password of the user account is known; hence the password has to be disabled while enabling the key pair verification. To disable the password authentication, edit /etc/ssh/sshd_config file where the settings for the SSH daemon are contained. In the file, the PasswordAuthentication has to be altered to NO, ChallengeResponseAuthentication should be altered to No as well. As the next step the sshd daemon has to be restarted for changes to take effect, which can be done with sudo systemctl reload sshd. Finally, the new key pair authentication method can be tested by giving ssh [email protected] in the terminal window.

Theory of The Keys and How They Work

Generate keys ssh synology nas pro

The key pair is a part of the SSH standard which is used to connect to a remote host over an unsecured network. As stated earlier, the key pair consists of two keys – public and private keys which are uploaded to the server side and kept on the client side respectively. The public key is denoted by .pub extension, and the private key doesn’t have any extension.

When the user is accessing the server, the SSH daemon installed on the server side requests the user for the SSH private key, if it’s provided the private key is compared against the public key in the server. If the private key corresponds to the public key, authentication is successful, otherwise it rejects the login request. By default, the key pair uses RSA which is a cryptographic algorithm to generate the keys. But there are other popular algorithms as well, such as DSA and ECDSA.

ssh-keygen Command Line Options

ssh-keygen is used to generate keys and it provides a number of options to ease the key pair management, tighten the security and increase the flexibility. The following options are some of the prominent options which may come handy when managing a server.


Generate Keys Ssh Synology Nas Pro

The Passphrase option is used to provide a secondary protection when a key pair is used to authenticate the user. What it does is to secure the private key with a password and consequently the user is required to provide the passphrase when logging in to the remote host. It asks during the key pair creation.

Change the Bit Strength

Bit strength refers to the key pair’s key size which defines how strong the key pair is. Nowadays the standard size is 2048 bits, but it used to be 1024 bits and is no longer acceptable as it’s speculated that many powerful hardware are capable of cracking anything up to 1024 bits or even above given the right amount of time. Fortunately, ssh-keygen currently supports higher bit strength values such as 2048 and its next fashionable number 4096 which is recommended if it’s possible due to the large bit strength. The bit strength value can be adjusted with –b command, if it’s omitted the default value – 1024 or 2048 depending on the ssh-keygen is used.

Comment Public Key

Commenting is applicable to the public key, and is useful in organizing the keys if there are a large number of keys involved. The typical usage of commenting is when multiple admins use a server, but still want to distinguish one key from another. The following format is used to add a comment when generating a key pair.

Change Passphrase of a Private Key

Like adding a passphrase when generating a key pair, the existing passphrase can also be changed. Since the passphrase is applicable to the private key which resides on the client side, the command has to be executed on the client side along with the name of the private key. This option takes 3 parameters, old password, new password and the private key to apply the changes.

Change the Cryptographic Algorithm

The Algorithm defines how the information in the key pair is encrypted in order to verify each other when the connection is being established. Ssh-keygen supports several popular algorithm types which are RSA, ECDSA, DSA, ED25519 and RSA1. Nowadays the popular algorithm among many servers is RSA due to its wide spread usage and relatively good security, however it’s currently being upgraded to the newer version ECDSA which is much lighter, and has a low bit value with a high security compared to RSA. ED25519 is the newest version among these, and therefore not many clients support it, but still server side implementation is possible at the moment. DSA is the oldest version among all these algorithms, and is no longer employed in most of the hosts as it’s not secure anymore. According to OpenSSH 7 standard the support for DSA will no longer be given. The format to use the algorithm is as following.

Generate Keys Ssh Synology Nas Free

SSH Key Gen Video Demonstration