Configure Public Key Authentication Over Ssh - Dell PowerEdge VRTX User Manual

Scheme Type
Message Integrity
Authentication

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
Date/Time
SSH PC1 x.x.x.x
09:00:00
SSH PC2 x.x.x.x
09:00:00
For more information about the sshpkauth, see the
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. The number should be between 768 and 4096.
NOTE: CMC may not display a message if you add keys less than 768 or greater than 4096, but when you try to
log in, these keys it fails.
Scheme
• ARCFOUR-128
• HMAC-SHA1-160
• HMAC-SHA1-96
• HMAC-MD5-128
• HMAC-MD5-96
Password
Login
06/16/2009
06/16/2009
Chassis Management Controller for PowerEdge VRTX RACADM
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