ViewSonic SC-T25 VTOS, User Manual

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My thin client can’t connect to anything and the
configuration tool says that it has no IP address. What can
I do?
Unplug the network cable, wait at least six seconds, and then plug in back in again.
This will reset the interface and trigger a new DHCP request.
Can I share my display with another person (for training or
troubleshooting purposes)?
Yes. RDP and HDX (ICA) protocols have their own session shadowing features –
which may or may not work with our client implementations – but VTOS also has a
VNC server capability that you can use. To initiate a shadow connection, first exit
fullscreen or defocus your fullscreen application (see “How do I get out of fullscreen
mode”, above), and then press control-alt-s and enter the hostname or IP address
and TCP port number of the shadower in the window that appears. You have
the option of either connecting to a listening VNC client over an SSL connection
(active mode), or setting up a TCP port forward via an SSH tunnel and awaiting
a connection (passive mode). Active mode has the advantage of using ordinary
HTTPS and being able to use a web proxy, which makes it suitable for highly secure
environments that don’t permit direct connection to the Internet. Passive mode has
the advantage of also providing an SSH port forward, allowing SSH as well as VNC
access from the remote SSH endpoint. Unlike typical VNC servers, both modes of
operation “dial out” to a remote server, which permits traversal of firewalls and NAT
gateways and implicitly ensures operator consent. For active mode, the shadowing
system must be running stunnel (www.stunnel.org) redirecting to a VNC client
application in listen mode (we recommend TurboVNC - www.virtualgl.org). Use of
SSL is mandatory. For passive mode, the shadowing system must be running an
SSH server that accepts publickey authentication and permits port forwarding, and
has a user with a ~/.ssh/authorized_keys file that contains VTOS’ SSH host public
keys. A thin client using VTOS can do both these things, and can therefore be used
to shadow sessions on another VTOS thin client.
The web browser / Citrix / whatever says that the server
SSL certificate is not trusted, but I’m sure that I have
installed the correct CA certificate. What’s wrong?
It’s likely that your thin client’s local clock is wrong. To verify this, you can start a
terminal using control-alt-t and then enter “date” in the window that appears. This
happens because the SC-T25 has no battery-backed clock, so unless it can contact
a network time server from which to get the current date and time, it will revert to a
nonsensical value such as the year 2000 or 2027 whenever its power is reset. By
default, it will try to contact Internet time servers, which may not succeed if there
is an intervening firewall or if hostname lookups are failing. To fix the problem,
use VDM3.0 or the local configuration tool to set the time server to the name or IP
address of a local NTP server that the client will be able to connect to. Typically
this would be the same as the local DNS server (if it is an Active Directory domain
controller) or default gateway (if it is a router appliance).