Novell ZENWORKS LINUX MANAGEMENT 7.2 IR2 - ADMINISTRATION GUIDE 09-25-2008, Руководство администратора

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Establishing SSH Tunneling 657
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The first argument is the local forwarding option, which says that the local fake port 5952
should be created and connected to the genuine port work:5950. The second argument is the
main non-option parameter to SSH, which tells it to connect to the device that runs the SSH
daemon.
2 In the PuTTY Security Alert dialog box, verify that the key matches with that of the “gateway”
device, then click
Yes .
3 To establish the SSH tunnel between “viewer” and “gateway,” you need to require
authentication to “gateway.” Specify a valid username and password of the “gateway” device in
the PuTTY dialog box, then click
Yes .
4
Any connections to port 5952 on your local management console would actually connect to
5950 on “work,” so instead of running a vnc viewer as
vncviewer work:50
run it as follows
vncviewer localhost :52
NOTE: If you are using the Linux VNC viewer to connect via SSH, when the viewer connects to a
server on the local management console, by default it uses VNC’s pixel encoding because this
generally gives better performance for local access. If this server is actually an SSHD redirecting the
data for another workstation, you can override this using the -tight option to the viewer or you can
send more data over the network.
J.3 Compression
SSH can also compress the data. This is particularly useful if the link between your management
console and the managed device is a slow one, such as a modem, but even on a faster network it can
be helpful, because encryption takes a certain amount of time and can slow the link down a little. To
add simple compression, use the -C option. For more control, set it up in your SSH configuration
files. To see how much your data is being compressed, use the -v option.