How do I configure an SSH server for RSA based authentication?
Complete these steps in order to configure the SSH server to perform RSA based authentication. Specify the Host name. Define a default domain name. Generate RSA key pairs. Configure SSH-RSA keys for user and server authentication. Configure the SSH username. Specify the RSA public key of the remote peer. Specify the SSH key type and version.
How do I check if SSH is enabled or disabled?
To check, simply enter privilege mode and use the show ip ssh command: %Please create RSA keys to enable SSH (and of atleast 768 bits for SSH v2). In the above output, the system is showing SSH support, but it’s currently disabled as no RSA key has been generated.
How to configure SSH to version 2 on Windows?
Configure ssh to version 2 using “ IP ssh version 2 ” and set the authentication times to 3 with “ IP ssh authentication-retries 3 ” command. Finally set the ssh timeout to 120 seconds with “ IP ssh time-out 120 ” command. The final step is to test the connectivity of ssh from PC1 with “ ssh -l Admin 192.168.1.1 ” command for command prompt.
How to configure SSH to use local username and password?
But here we configure ssh to use local username and password. Configure the router to accept only ssh connection with “ transport input ssh ” command. Configure ssh to version 2 using “ IP ssh version 2 ” and set the authentication times to 3 with “ IP ssh authentication-retries 3 ” command.
What is the minimum key size used for SSH ver2?
768 bitsIn the above output, the system is showing SSH support, but it's currently disabled as no RSA key has been generated. It is also worth noting that a key of at least 768 bits must be generated to enable SSHv2.
What IOS commands are mandatory to enable SSHv2 on a Cisco network device?
SSH Version 2 configuration on a Cisco router IOS –Configure Hostname and DNS Domain. hostname R1. aaa new-model. username Cisco password Cisco. ... Step 2 – Generate RSA key to be used. ip ssh rsa keypair-name sshkey. ... Step 3 – Enable SSH transport support for the virtual type terminal (vty) line vty 0 4.
What is the difference in line vty 0 4 and 5 15?
VTY lines are usually used for creating out-of-band management sessions to devices. If a password is not supplied on a vty line, that line cannot be used for managing the device. In some cases administrators may decide to let junior staff to use lines 0 - 4 and senior staff to use lines 5 - 15.
What is the meaning of line Vty 0 4?
VTY is solely used for inbound connections to the device. These connections are all virtual with no hardware associated with them. Related Blog – VTY Password. The abstract “0 – 4” means that the device can allow 5 simultaneous virtual connections which may be Telnet or SSH.
How do I create an SSH key?
Open a terminal and use the ssh-keygen command with the -C flag to create a new SSH key pair. Replace the following: KEY_FILENAME : the name for your SSH key file. For example, a filename of my-ssh-key generates a private key file named my-ssh-key and a public key file named my-ssh-key.
What is SSH configuration?
ssh/config – is the user-specific/custom configuration file. It has configurations that apply to a specific user. It therefore overrides default settings in the system-wide config file. This is the file we will create and use.
What is the meaning of Vty 0 15?
Lines 0 15 is vty lines 0, 1, 2 ,3 ,4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 and 15. for example if you were type in global configuration mode, line vty 0 15 you will enter configuration for lines 0-15.
What does Vty stand for?
Virtual TeletypeWhat Does Virtual Teletype (VTY) Mean? Virtual teletype (VTY) is a command line interface (CLI) created in a router and used to facilitate a connection to the daemon via Telnet, a network protocol used in local area networks. To connect to a VTY, users must present a valid password.
What is the Vty line on a Cisco configuration?
The virtual terminal or “VTY” lines are virtual lines that allow connecting to the device using telnet or Secure Shell (SSH). Cisco devices can have up to 16 VTY lines.
What does the command line Vty 0 1 mean?
What does the command line vty 0 1 mean? The "0 1" represents the number of vty lines to which the following configu- ration parameters will be applied. The two virtual terminal connections are identified as 0, 1.
How many Vty lines are on a router?
5 vty linesBy default all routers have 5 vty lines (factory defaults). Unless you configure the remaining available lines, there is no need for them to be protected.
How do I enable IPv6 routing?
How to set up an IPv6 Internet connection on the Wi-Fi Routers (new logo)Log in to the web-based interface of the router. ... Go to Advanced > IPv6.Enable IPv6 and select the internet connection type provided by your ISP. ... Fill in information as required by different connection types. ... Configure LAN ports.More items...•
What command will display a context sensitive help of an IOS switch?
The Cisco IOS® command-line interface (CLI) offers context-sensitive help, a useful tool if you are a new user because at any time during an EXEC session, you can type a question mark (?) to get help.
What is encrypted with the enable secret command?
What is encrypted with the enable secret command? the privileged executive mode password.
What is initially entered at the CLI of the Cisco IOS when typing a command sequence?
What is initially entered at the CLI of the Cisco IOS when typing a command sequence? C. The IOS command parser inspects the first entries of a command sequence, expecting to identify a known command.
What is crypto key generate RSA?
Syntax: crypto key { generate | zeroize } rsa [ modulus modulus-size ] The generate keyword places an RSA host key pair in the flash memory and enables SSH on the device, if it is not already enabled. The optional [modulus modulus-size ] parameter specifies the modulus size of the RSA key pair, in bits.
What is Rt1 in config line?
Rt1 (config-line)# transport input ssh (This allows ONLY SSH and disables others, use a “?” after transport input to see other options)
What is authentication in computer?
authentication- Authentication to reliably determine the identity of the connecting computer.
Does SSH2 use TCP?
SSH uses TCP as its transport layer protocol and uses well-known port number 22. Now, to allow Telnet or SSH access to any device like a router or a switch, the device needs an IP address.
How to access remote access server?
On the Remote Access server, open the Remote Access Management console: On the Start screen, type, type Remote Access Management Console, and then press ENTER. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Yes.
Where is the Configure button in Remote Access Management Console?
In the middle pane of the Remote Access Management console, in the Step 3 Infrastructure Servers area, click Configure.
How to deploy DirectAccess for remote management only?
In the DirectAccess Client Setup Wizard, on the Deployment Scenario page , click Deploy DirectAccess for remote management only, and then click Next.
How to add roles and features to DirectAccess?
On the DirectAccess server, in the Server Manager console, in the Dashboard, click Add roles and features.
How to install Remote Access on DirectAccess?
On the DirectAccess server, in the Server Manager console, in the Dashboard, click Add roles and features. Click Next three times to get to the server role selection screen. On the Select Server Roles dialog, select Remote Access, and then click Next.
How to configure deployment type?
On the Remote Access server, open the Remote Access Management console: On the Start screen, type, type Remote Access Management Console, and then press ENTER. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Yes.
How to add domain suffix in remote access?
On the DNS Suffix Search List page, the Remote Access server automatically detects domain suffixes in the deployment. Use the Add and Remove buttons to create the list of domain suffixes that you want to use. To add a new domain suffix, in New Suffix, enter the suffix, and then click Add. Click Next.
What is SSH authentication?
SSH uses either local security or the security protocol that is configured through AAA on your router for user authentication. When you configure AAA, you must ensure that the console is not running under AAA by applying a keyword in the global configuration mode to disable AAA on the console.
How many steps are required to enable SSH on Cisco router?
There are four steps required to enable SSH support on a Cisco IOS router:
How to prevent non-SSH connections?
If you want to prevent non-SSH connections, add the transport input ssh command under the lines to limit the router to SSH connections only . Straight (non-SSH) Telnets are refused.
What does show ssh mean?
show ssh âDisplays the status of SSH server connections.
What happens if you reject SSH?
If your SSH configuration commands are rejected as illegal commands, you have not successfully generated a RSA key pair for your router. Make sure you have specified a host name and domain. Then use the crypto key generate rsa command to generate an RSA key pair and enable the SSH server.
What is SSH in a network?
Secure Shell (SSH) is a protocol which provides a secure remote access connection to network devices. Communication between the client and server is encrypted in both SSH version 1 and SSH version 2. Implement SSH version 2 when possible because it uses a more enhanced security encryption algorithm. This document discusses how to configure and ...
Why isn't the connect button enabled?
The Connect button is not enabled if you do not enter the host name and username. This screenshot shows that the login banner is displayed when Secure Shell connects to the router. Then, the login banner password prompt displays. The PuTTY client does not require the username to initiate the SSH connection to the router.
What is SSH on Cisco router?
The Secure Shell (SSH) is a cryptographic network protocol for operating network services securely over an unsecured network. The best-known example application is for remote login to computer systems by users.
What is SSH in network?
SSH provides a secure channel over an unsecured network in a client-server architecture, connecting an SSH client application with an SSH server. Common applications include remote command-line login and remote command execution, but any network service can be secured with SSH.
What command is used to restrict remote access to a router?
We’ll use the transport input ssh command under the VTY section to restrict remote access using SSH only. Note that we can also use Access-lists to restrict SSH connections to our router:
Why is the password command not used in VTY 0 4?
Note: the password command used under line vty 0 4 section is completely optional and not used in our case because of the login authentication default command which forces the router to use the AAA mechanism for all user authentication.
What is SSH port?
Secure Shell (SSH) provides a secure and reliable mean of connecting to remote devices. It’s an encrypted network protocol that allows users to safely access equipment via command line interface sessions. SSH makes use of TCP port 22 which’s assigned to secure logins, file transfer and port forwarding.
Is telnet a security risk?
This will ensure that insecure services such as Telnet cannot be used to access the router. Telnet sends all information unencrypted, including user name/password, and is therefore considered a security risk.
Does Cisco router support SSH?
The first step involves examining whether your Cisco router’s IOS supports SSH or not . Most modern Cisco routers support SSH, so this shouldn’t be a problem.
Information About SSHv2 and Telnet
You can use the SSHv2 server to enable an SSH client to make a secure, encrypted connection to the Cisco CG-OS router. SSHv2 uses strong encryption for authentication. The SSHv2 server in the Cisco CG-OS software can interoperate with publicly and commercially available SSHv2 clients.
Prerequisites
Configure IP on a Layer 3 interface, out-of-band on the mgmt 0 interface, or inband on an Ethernet interface.
Configuring SSHv2
You can generate an SSHv2 server key based on your security requirements. The default SSHv2 server key is an RSA key that the Cisco CG-OS router generates using 1024 bits.
Configuring Telnet
You can enable the Telnet server on the Cisco CG-OS router. By default, the Telnet server is disabled.
Introduction
Prerequisites
Test Authentication
Optional Configuration Sets
Debug and Show Commands
Sample Debug Output
Tips
- If your SSH configuration commands are rejected as illegal commands, you have not successfully generated a RSA key pair for your router. Ensure you have specified a host name and domain. Then use t...
- When you configure RSA key pairs, you can get these error messages:
- The number of allowable SSH connections is limited to the maximum number of vty configur…
- If your SSH configuration commands are rejected as illegal commands, you have not successfully generated a RSA key pair for your router. Ensure you have specified a host name and domain. Then use t...
- When you configure RSA key pairs, you can get these error messages:
- The number of allowable SSH connections is limited to the maximum number of vty configured for the router. Each SSH connection uses a vtyresource.
- SSH uses either local security or the security protocol configured through AAA on your router for user authentication. When you configure AAA, you must ensure that the console is not run under AAA....
