Extreme Networks Summit Summit24, Installation And User Manual

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Using Secure Shell 2 (SSH2)
Summit24e3 Switch Installation and User Guide 53
To re-enable Telnet on the switch, at the console port use the following:
enable telnet
You must be logged in as an administrator to enable or disable Telnet.
Using Secure Shell 2 (SSH2)
Secure Shell 2 (SSH2) is a feature of ExtremeWare that allows you to encrypt Telnet session data
between the switch and a network administrator using SSH2 client software. The ExtremeWare SSH2
switch application is based on the Data Fellows
™
SSH2 server implementation. It is highly
recommended that you use the F-Secure

SSH client products from Data Fellows corporation. These
applications are available for most operating systems. For more information, refer to the Data Fellows
website at:
http://www.datafellows.com.
NOTE
SSH2 is compatible with the Data Fellows SSH2 client version 2.0.12 or above. SSH2 is not compatible
with SSH1.
Enabling SSH2
Because SSH2 is currently under U.S. export restrictions, before enabling SSH2, you must first obtain a
security license from Extreme Networks. The procedure for obtaining a security license key is described
in Chapter 3, “ExtremeWare Overview”.
To enable SSH2, use the following command:
enable ssh2 {port <tcp_port_number>}
An authentication key must be generated for each SSH2 session. This can be done automatically by the
switch or by the client application. To have the key generated by the switch, use the following
command:
config ssh2 key {pregenerated}
If you do not select automatic key generation, you are prompted to enter the key when you enable
SSH2.
You can specify a TCP port number to be used for SSH2 communication. By default the TCP port
number is 22.
The supported cipher is 3DES-CBC. The supported key exchange is DSA.
For additional information on the SSH protocol refer to [FIPS-186] Federal Information Processing
Standards Publication (FIPSPUB) 186, Digital Signature Standard, 18 May 1994. This can be download
from: ftp://ftp.cs.hut.fi/pub/ssh. General technical information is also available from
http://www.ssh.fi.