Web Management Guide-R07

Table Of Contents
Chapter 12
| Security Measures
Configuring the Secure Shell
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Public Key Authentication – When an SSH client attempts to contact the switch,
the SSH server uses the host key pair to negotiate a session key and encryption
method. Only clients that have a private key corresponding to the public keys
stored on the switch can access it. The following exchanges take place during
this process:
Authenticating SSH v2 Clients
a. The client first queries the switch to determine if public key
authentication using a preferred algorithm is acceptable.
b. If the specified algorithm is supported by the switch, it notifies the
client to proceed with the authentication process. Otherwise, it rejects
the request.
c. The client sends a signature generated using the private key to the
switch.
d. When the server receives this message, it checks whether the supplied
key is acceptable for authentication, and if so, it then checks whether
the signature is correct. If both checks succeed, the client is
authenticated.
Note:
The SSH server supports up to eight client sessions. The maximum number
of client sessions includes both current Telnet sessions and SSH sessions.
Note:
The SSH server can be accessed using any configured IPv4 or IPv6 interface
address on the switch.
Configuring the
SSH Server
Use the Security > SSH (Configure Global) page to enable the SSH server and
configure basic settings for authentication.
Note:
You must generate RSA host keys before enabling the SSH server. See
“Generating the Host Key Pair” on page 272.
Parameters
These parameters are displayed:
SSH Server Status – Allows you to enable/disable the SSH server on the switch.
(Default: Disabled)
Version – The Secure Shell version number. Version 2.0 is displayed and the
switch supports management access only from SSH Version 2.0 clients.
Authentication Timeout – Specifies the time interval in seconds that the SSH
server waits for a response from a client during an authentication attempt.
(Range: 1-120 seconds; Default: 120 seconds)