Telnet versus SSH

1. Cisco Rsa Key
2. Generate A Rsa Crypto Key
3. Crypto Key Generate Rsa Command
4. Cisco Switch Can't Generate Crypto Key Rsa
5. Cisco Crypto Key Gen Rsa

Show crypto key mypubkey rsa: Shows information about the SSL certificate If you’d like to learn more about on how to configure SSH on a Cisco router I recommend you read through this documentation: Configuring Secure Shell on Routers and Switches Running Cisco IOS. Oct 02, 2015  SSH Config and crypto key generate RSA command. Use this command to generate RSA key pairs for your Cisco device (such as a router). Keys are generated in pairs–one public RSA key and one private RSA key. If your router already has RSA keys when you issue this command, you will be warned and prompted to replace the existing keys. Dec 26, 2013  so it looks as if there is no point in the 'crypto key generate rsa' command if i follow it up with the 'crypto key generate rsa usage-keys label sshkeys mod 1024' command, i just wanted to make sure the first wasn't need for the second to work or something screwy like that.

Many people continue to use Telnet for sensitive applications or access to critical systems. Telnet is CLEARTEXT, so all the data, including the login id is visible is someone intercepts that session

1. Nov 29, 2017  crypto key generate rsa general-keys modulus 1024 (or 2048) without enabling 'ip http secure-server'. So, you don't need to enable 'ip http secure-server' at all to use SSH, just generate the RSA key with the 'crypto key generate' command as mentioned above.
2. Config t crypto key generate rsa exit Then ssh to the router and complete the config. Or just enable telnet if you can get away with it. Config t vty 0 4 transport input ssh telnet exit I have a perl script that does this to reset enable passwords.

Here’s what this looks like using Wireshark an Open Source Protocol Analyzer when we use the Follow TCP Stream feature in Wireshark.

The next characters are red (the character I typed) and blue (the characters echoed back)

You clearly see the User Verification Prompt.Here's the telnet trace file.

Cisco Rsa Key

Below you can see me typing in my username;

In this screenshot below you can see me entering the commandenable and the the enable password.

How to Enable SSH Version 1 on Cisco

Before you can enable SSH you need to assign individual (or group) user IDs and passwords.

These are just login id's and are required regardless if you use Telnet or SSH.

To enable locally administered user IDs, use the following set of configuration commands. I would not suggest using the nopassword parameter.

Put your own data in the italized text.

Now when you telnet into the device you should see the Username prompt

Now that you have login id's created you can turn on SSH version 1.

To enable SSH, use the following set of configuration commands. I would not suggest using the nopassword parameter.

Put your own data in the italized text.

Now we'll try to capture the SSH login and as you can see the login data is no longer in clear text. Here's the SSH 1 trace file.

Generate A Rsa Crypto Key

The moral of the story is not to use Cleartext logins if the device or application is sensitive.

Crypto Key Generate Rsa Command

To upgrade to even more secure SSH version 2, type in the following commands

the SSH version 2 trace files are here

Cisco Switch Can't Generate Crypto Key Rsa

In this write up I used;

Cisco Crypto Key Gen Rsa

• Wireshark Protocol Analyzer(free)

• Putty Telnet/SSH Client(free)

• Cisco Switch(not free)