Crypto Key Generate Cisco 3750
Contents
Introduction
This document gives step-by-step instructions to configure Secure Shell (SSH) Version 1 on Catalyst switches running Catalyst OS (CatOS). World of warcraft cd key generator battlenet. The version tested is cat6000-supk9.6-1-1c.bin.
Prerequisites
Requirements
This table shows the status of SSH support in the switches. Registered users can access these software images by visiting the Software Center.
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. Mar 09, 2014 How to Enable SSH on Cisco Switch, Router and ASA (Cisco 3750 Catalyst Switch) February 23, 2014 March 9, 2014 Farzand Ali Leave a comment By default, when you configure a Cisco device, you have to use the console cable and connect directly to the system to access it. How to configure SSH on Cisco IOS. In a previous lesson, I explained how you can use telnet for remote access to your Cisco IOS devices. The problem with telnet is that everything is sent in plaintext, for that reason you shouldn’t use it. #crypto key generate rsa The name for the keys will be: R1.NETWORKLESSONS.LOCAL Choose the size of.
| CatOS SSH | |
|---|---|
| Device | SSH Support |
| Cat 4000/4500/2948G/2980G (CatOS) | K9 images as of 6.1 |
| Cat 5000/5500 (CatOS) | K9 images as of 6.1 |
| Cat 6000/6500 (CatOS) | K9 images as of 6.1 |
| IOS SSH | |
| Device | SSH Support |
| Cat 2950* | 12.1(12c)EA1 and later |
| Cat 3550* | 12.1(11)EA1 and later |
| Cat 4000/4500 (Integrated Cisco IOS Software)* | 12.1(13)EW and later ** |
| Cat 6000/5500 (Integrated Cisco IOS Software)* | 12.1(11b)E and later |
| Cat 8540/8510 | 12.1(12c)EY and later, 12.1(14)E1 and later |
| No SSH | |
| Device | SSH Support |
| Cat 1900 | no |
| Cat 2800 | no |
| Cat 2948G-L3 | no |
| Cat 2900XL | no |
| Cat 3500XL | no |
| Cat 4840G-L3 | no |
| Cat 4908G-L3 | no |
* Configuration is covered in Configuring Secure Shell on Routers and Switches Running Cisco IOS.
- The private key has to be protectedmake sure it doesn’t leave your computer. In this lesson, we will generate a public and private key on a Windows and Linux computer. We will then add the public key to a Cisco IOS router and use it for SSH authentication.
- Jul 03, 2015 username cisco password 0 cisco!- Step 2: Configure the DNS domain of the router. Ip domain-name rtp.cisco.com!- Step 3: Generate an SSH key to be used with SSH. Crypto key generate rsa. Ip ssh time-out 60. Ip ssh authentication-retries 2!- Step 4: By default the vtys' transport is Telnet. In this case,!- Telnet is disabled and only.
** There is no support for SSH in 12.1E train for Catalyst 4000 running Integrated Cisco IOS Software.
Refer to Encryption Software Export Distribution Authorization Form in order to apply for 3DES.
This document assumes that authentication works prior to implementation of SSH (through the Telnet password, TACACS+) or RADIUS. SSH with Kerberos is not supported prior to the implementation of SSH.
Components Used
This document addresses only the Catalyst 2948G, Catalyst 2980G, Catalyst 4000/4500 series, Catalyst 5000/5500 series, and Catalyst 6000/6500 series running the CatOS K9 image. For more details, refer to the Requirements section of this document.
The information presented in this document was created from devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If you are working in a live network, ensure that you understand the potential impact of any command before using it.
Conventions
For more information on document conventions, see the Cisco Technical Tips Conventions.
Network Diagram
Switch Configuration
Disabling SSH
In some situations it may be neccessary to disable SSH on the switch. You must verify whether SSH is configured on the switch and if so, disable it.
To verify if SSH has been configured on the switch, issue the show crypto key command. If the output displays the RSA key, then SSH has been configured and enabled on the switch. An example is shown here.
To remove the crypto key, issue the clear crypto key rsa Lana del rey honeymoon download zip. command to disable SSH on the switch. An example is shown here.
debug in the Catalyst
To turn on debugs, issue the set trace ssh 4 command.
Crypto Key Generate Rsa Cisco 3750
To turn off debugs, issue the set trace ssh 0 command.
debug Command Examples of a Good Connection
Solaris to Catalyst, Triple Data Encryption Standard (3DES), Telnet Password
Solaris
Catalyst
PC to Catalyst, 3DES, Telnet Password
Catalyst
Solaris to Catalyst, 3DES, Authentication, Authorization, and Accounting (AAA) Authentication
Solaris
Catalyst
debug Command Examples of What Can Go Wrong
Catalyst debug with Client Attempting [unsupported] Blowfish Cipher
Catalyst debug with Bad Telnet Password
Catalyst debug with Bad AAA Authentication
Troubleshoot
This section deals with different troubleshooting scenarios related to SSH configuration on Cisco switches.
Cannot Connect to Switch through SSH
Problem:
Cannot connect to the switch using SSH.
The debug ip ssh command shows this output:
Solution:
This problem occurs because of either of these reasons:
Crypto Key Generate
New SSH connections fail after changing the hostname.
SSH configured with non-labeled keys (having the router FQDN).
The workarounds for this problem are:
If the hostname was changed and SSH is no longer working, then zeroize the new key and create another new key with the proper label.
Do not use anonymous RSA keys (named after the FQDN of the switch). Use labeled keys instead.
In order to resolve this problem forever, upgrade the IOS software to any of the versions in which this problem is fixed.
A bug has been filed about this issue. For more information, refer to Cisco bug ID CSCtc41114 (registered customers only) .