Configuring the Switch
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e. The switch compares the decrypted bytes to the original bytes it sent. If the
two sets match, this means that the client's private key corresponds to an
authorized public key, and the client is authenticated.
Notes: 1. To use SSH with only password authentication, the host public key must still
be given to the client, either during initial connection or manually entered into
the known host file. However, you do not need to configure the client’s keys.
2. The SSH server supports up to four client sessions. The maximum number
of client sessions includes both current Telnet sessions and SSH sessions.
Generating the Host Key Pair
A host public/private key pair is used to provide secure communications between an
SSH client and the switch. After generating this key pair, you must provide the host
public key to SSH clients and import the client’s public key to the switch as
described in the proceeding section (Command Usage).
Field Attributes
•Public-Key of Host-Key – The public key for the host.
- RSA (Version 1): The first field indicates the size of the host key (e.g., 1024), the
second field is the encoded public exponent (e.g., 65537), and the last string is
the encoded modulus.
- DSA (Version 2): The first field indicates that the encryption method used by
SSH is based on the Digital Signature Standard (DSS). The last string is the
encoded modulus.
•Host-Key Type – The key type used to generate the host key pair (i.e., public and
private keys). (Range: RSA (Version 1), DSA (Version 2), Both: Default: RSA)
The SSH server uses RSA or DSA for key exchange when the client first
establishes a connection with the switch, and then negotiates with the client to
select either DES (56-bit) or 3DES (168-bit) for data encryption.
•Save Host-Key from Memory to Flash – Saves the host key from RAM (i.e.,
volatile memory to flash memory. Otherwise, the host key pair is stored to RAM by
default. Note that you must select this item prior to generating the host-key pair.
•Generate – This button is used to generate the host key pair. Note that you must
first generate the host key pair before you can enable the SSH server on the SSH
Server Settings page.
•Clear – This button clears the host key from both volatile memory (RAM) and
non-volatile memory (Flash).