Users Guide

Table 32. Cryptography Schemes (continued)
Scheme Type Scheme
• HMAC-MD5-128
• HMAC-MD5-96
Authentication Password
Configure Public Key Authentication Over SSH
You can configure up to six public keys that can be used with the service username over an SSH interface. Before adding or deleting
public keys, make sure to use the view command to see what keys are already set up, so that a key is not accidentally overwritten or
deleted. The service username is a special user account that can be used when accessing the CMC through SSH. When the PKA over
SSH is set up and used correctly, you need not enter username or passwords to log in to the CMC. This can be very useful to set up
automated scripts to perform various functions.
NOTE: There is no GUI support for managing this feature, you can use only the RACADM.
When adding new public keys, make sure that the existing keys are not already at the index, where the new key is added. CMC does not
perform checks to ensure previous keys are deleted before a new one is added. As soon as a new key is added, it is automatically in effect
as long as the SSH interface is enabled.
When using the public key comment section of the public key, remember that only the first 16 characters are utilized by the CMC. The
public key comment is used by the CMC to distinguish SSH users when using the RACADM getssninfo command, because all the PKA
users use the service username to log in.
For example, if two public keys are set up one with comment PC1 and one with comment PC2:
racadm getssninfo
Type User IP Address Login
Date/Time
SSH PC1 x.x.x.x 06/16/2009
09:00:00
SSH PC2 x.x.x.x 06/16/2009
09:00:00
For more information about the sshpkauth, see the Chassis Management Controller for PowerEdge VRTX RACADM Command Line
Reference Guide.
Generating Public Keys for Systems Running Windows
Before adding an account, a public key is required from the system that accesses the CMC over SSH. There are two ways to generate the
public/private key pair: using PuTTY Key Generator application for clients running Windows or ssh-keygen CLI for clients running Linux.
This section describes simple instructions to generate a public/private key pair for both applications. For additional or advanced usage of
these tools, see the application Help.
To use the PuTTY Key Generator to create a basic key for clients running Windows:
1. Start the application and select SSH-2 RSA or SSH-2 DSA for the type of key to generate (SSH-1 is not supported).
2. Enter the number of bits for the key. Ensure that the RSA key size is between 1024 and 4096.
NOTE:
• The recommended DSA key length is 1024.
• CMC may not display a message if you add keys less than 1024 or greater than 4096, but when you try to log in
with these keys, CMC stops responding.
• For DSA keys greater than 2048, use the following RACADM command. CMC accepts RSA keys up to key
strength 4096, but the recommended key strength is 1024.
racadm -r 192.168.8.14 -u root -p calvin sshpkauth -i svcacct -k 1 -p 0xfff -f
dsa_2048.pub
3. Click Generate, and move the mouse in the window as directed.
After the key is created, you can modify the key comment field.
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Configuring CMC to Use Command Line Consoles