• Cisco Rsa Key
• Generate Rsa Crypto Key Cisco

Cisco 3850 VTY (SSH) lines hung by Prime - bug Hi, It seems we have run into this bug with our deployment of the 3850 switches. Bug ID is: keyCSCuv84149key We are currently running IOS XE version 3.03.03 and have had 3 switch stacks with this bug in the last 2 weeks and we are now concerned that it will continue to happen. I did a little research and found out that if I removed the rsa key by using this command ' crypto key zeroize rsa' and then added the 'crypto key generate rsa generate-keys modulus 1024, then that would work. Any thoughts? No service pad. No service password-encryption. Hostname Sales-SW-ACC2. Ip domain name my.company.come.

Contents

Nov 14, 2019 When we generate RSA key pair on a cisco router or firewall, how 'exactly' it works? Because we dont move any keys anywhere. I know we 'have' to generate it on every new device, to allow ssh, but im missing a key part of the theory on this, when i try to compare with normal ssh access to servers. Apr 18, 2016 For SSH to be configure on a Cisco device a few things need to be configured. Hostname, Domain-name, enable SSH and generate the key. Pluralsight have an excellent guide, I think it's important that if you use and support a technology, you should know something about it, have a read, it's nice and easy, and explained very clearly. Cisco IOS Security Command Reference: Commands A to C, Cisco IOS XE Release 3SE (Catalyst 3850 Switches) 1. Crypto key generate rsa. TogenerateRivest,Shamir,andAdelman(RSA)keypairs,usethecryptokeygeneratersacommandinglobal configurationmode. Jul 21, 2012  – To define a default domain name that the Cisco IOS software uses to complete unqualified host names. R1(config)# crypto key generate rsa – To generate RSA key pairs. The name for the keys will be: R1.ccie.com Choose the size of the key modulus in the range of 360 to 2048 for your General purpose keys. Choosing a key modulus.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http:/​/​www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Prerequisites for Configuring the Switch for Secure Shell (SSH) and Secure Copy Protocol (SCP)

The following are the prerequisites for configuring the switch for secure shell (SSH):

• For SSH to work, the switch needs an RSA public/private key pair. This is the same with Secure Copy Protocol (SCP), which relies on SSH for its secure transport.
• Before enabling SCP, you must correctly configure SSH, authentication, and authorization on the switch.
• Because SCP relies on SSH for its secure transport, the router must have an Rivest, Shamir, and Adelman (RSA) key pair.
• SCP relies on SSH for security.
• SCP requires that authentication, authorization, and accounting (AAA) authorization be configured so the router can determine whether the user has the correct privilege level.
• A user must have appropriate authorization to use SCP.
• A user who has appropriate authorization can use SCP to copy any file in the Cisco IOS File System (IFS) to and from a switch by using the copy command. An authorized administrator can also do this from a workstation.

Restrictions for Configuring the Switch for SSH

The following are restrictions for configuring the switch for secure shell.

• The switch supports Rivest, Shamir, and Adelman (RSA) authentication.
• SSH supports only the execution-shell application.
• The SSH server and the SSH client are supported only on DES (56-bit) and 3DES (168-bit) data encryption software.
• The switch supports the Advanced Encryption Standard (AES) encryption algorithm with a 128-bit key, 192-bit key, or 256-bit key. However, symmetric cipher AES to encrypt the keys is not supported.
• This software release does not support IP Security (IPSec).
• When using SCP, you cannot enter the password into the copy command. You must enter the password when prompted.

Information about SSH

Secure Shell (SSH) is a protocol that provides a secure, remote connection to a device. SSH provides more security for remote connections than Telnet does by providing strong encryption when a device is authenticated. This software release supports SSH Version 1 (SSHv1) and SSH Version 2 (SSHv2).

SSH and Switch Access

For SSH configuration examples, see the “SSH Configuration Examples” section in the “Configuring Secure Shell” section in the “Other Security Features” chapter of the Cisco IOS Security Configuration Guide, Cisco IOS Release 12.4.

SSH functions the same in IPv6 as in IPv4. For IPv6, SSH supports IPv6 addresses and enables secure, encrypted connections with remote IPv6 nodes over an IPv6 transport.

SSH Servers, Integrated Clients, and Supported Versions

The SSH feature has an SSH server and an SSH integrated client, which are applications that run on the switch. You can use an SSH client to connect to a switch running the SSH server. The SSH server works with the SSH client supported in this release and with non-Cisco SSH clients. The SSH client also works with the SSH server supported in this release and with non-Cisco SSH servers.

The switch supports an SSHv1 or an SSHv2 server.

The switch supports an SSHv1 client.

SSH supports the Data Encryption Standard (DES) encryption algorithm, the Triple DES (3DES) encryption algorithm, and password-based user authentication.

SSH also supports these user authentication methods:

• TACACS+
• RADIUS
• Local authentication and authorization

SSH Configuration Guidelines

Follow these guidelines when configuring the switch as an SSH server or SSH client:

• An RSA key pair generated by a SSHv1 server can be used by an SSHv2 server, and the reverse.
• If the SSH server is running on a stack master and the stack master fails, the new stack master uses the RSA key pair generated by the previous stack master.
• If you get CLI error messages after entering the crypto key generate rsa global configuration command, an RSA key pair has not been generated. Reconfigure the hostname and domain, and then enter the crypto key generate rsa command. For more information, see Related Topics below.
• When generating the RSA key pair, the message No host name specified might appear. If it does, you must configure a hostname by using the hostname global configuration command.
• When generating the RSA key pair, the message No domain specified might appear. If it does, you must configure an IP domain name by using the ip domain-name global configuration command.
• When configuring the local authentication and authorization authentication method, make sure that AAA is disabled on the console.

Secure Copy Protocol Overview

The Secure Copy Protocol (SCP) feature provides a secure and authenticated method for copying switch configurations or switch image files. SCP relies on Secure Shell (SSH), an application and a protocol that provides a secure replacement for the Berkeley r-tools.

Cisco Rsa Key

For SSH to work, the switch needs an RSA public/private key pair. This is the same with SCP, which relies on SSH for its secure transport.

Because SSH also relies on AAA authentication, and SCP relies further on AAA authorization, correct configuration is necessary.

• Before enabling SCP, you must correctly configure SSH, authentication, and authorization on the switch.
• Because SCP relies on SSH for its secure transport, the router must have an Rivest, Shamir, and Adelman (RSA) key pair.

Secure Copy Protocol Concepts

The Secure Copy Protocol (SCP) feature provides a secure and authenticated method for copying switch configurations or switch image files. SCP relies on Secure Shell (SSH), an application and a protocol that provides a secure replacement for the Berkeley r-tools.

To configure the Secure Copy feature, you should understand the SCP concepts.

The behavior of SCP is similar to that of remote copy (rcp), which comes from the Berkeley r-tools suite, except that SCP relies on SSH for security. SCP also requires that authentication, authorization, and accounting (AAA) authorization be configured so the router can determine whether the user has the correct privilege level.

For information about how to configure and verify SCP, see the “Secure Copy Protocol” section in the Cisco IOS Security Configuration Guide: Securing User Services, Release 12.4.

How to Configure SSH

Setting Up the Switch to Run SSH

Beginning in privileged EXEC mode, follow these steps to set up your switch to run SSH:

Configure user authentication for local or remote access. This step is required. For more information, see Related Topics below.

Generate Rsa Crypto Key Cisco

1.configureterminal


2.hostnamehostname


3.ip domain-namedomain_name
Matlab activation key generator r2015a.

4.crypto key generate rsa


5.end

Configuring the SSH Server

Beginning in privileged EXEC mode, follow these steps to configure the SSH server:

1.configureterminal


/bfme-1-cd-key-generator.html. 2.ip sshversion [12]


3.ip ssh {timeoutsecondsauthentication-retriesnumber}


4.Use one or both of the following:

• transport input ssh

5.end

Monitoring the SSH Configuration and Status

For more information about these commands, see the “Secure Shell Commands” section in the “Other Security Features” chapter of the Cisco IOS Security Command Reference .

Additional References

Related Documents

Error Message Decoder

MIBs

Technical Assistance