Ultravnc for remote computer support
A little while back I talked some about TightVNC which for a long time has been my favorite implementation of a remote framebuffer, or remote desktop viewing protocol known as VNC (Virtual Network Computing.) The original VNC (now realvnc) came out of AT&T research labs in the UK and has developed quite a following as a pcanywhere alternative depending on what you need to do. Now, tightvnc has been a favorite of mine for a couple reasons. 1) it’s well supported under linux which is a must for me…, 2) it excels at slower speed connections. Which is also fairly important to me.
Now, let me give an example. There is one business in particular that I’ve used TightVNC for remote desktop support. Basically, they have a linux server (which gives remote ssh access). They each have a desktop icon that says “Allow remote administration” which when clicked launches tightvnc. Then I connect through ssh and check to find the IP address on the internal lan that is acting as the VNC server, then…. I gateway through the server to the internal address… like this…
vncviewer -via remotesitewithsshserver -encodings tight -quality 3 -compresslevel 7 192.168.0.20:0
This calls up a ssh login at the “remotesitewithsshserver” machine, which then passes through to the machine at 192.168.0.20 running vnc on the first display. There are a lot of advantages, the big one being end to end ssh encryption over the hostile internet. This is VERY nice in my opinion (this way even the vnc login is encrypted).
However, what if you have a user to support that’s behind a firewall and there’s no ssh server to the outside world on their network? Yuck… usually that means port forwarding to a specific machine, what if you need several and what if you don’t WANT to leave port forwards up all the time? What to do what to do?
As I was looking into other implementations of VNC I ran across Ultravnc which is yet another open source implementation of the vnc protocol. What makes it different? Well, a couple things it is primarily Windows only (which is a bit of a negative for me…), it also gives some nice toolbar icons when viewing a remote desktop. (Tightvnc you have to right click on the programs titlebar to get useful menu items.) This gives you file uploads (if running ultravnc at both ends), send ctrl-esc, send ctrl-alt-del, it deals with scaling the remote desktop more gracefully than tightvnc seems to for me. So, all in all there are a few nice ease of use improvements.
That’s not what got me REALLY excited about UltraVNC though. What really got my attention was this…
UltraVNC Single Click otherwise known as UltraVNC SC. It takes advantage of a vnc feature that I’ve little understood (or tried) until now. That is the -listen directive. Let’s say you are expecting a connection from a VNC server, with a vncviewer launched with the -listen command the server can actually contact the viewer. Let me try to put this another way.
End user with computer problems is behind a firewall with 10 other machines, no port-forwarding. You are at your home network trying to support remotely, but have the age-old dillemma that you can’t see what’s on the other screen. You direct the end user to download you’re personalized version of the ultravnc server which “automagically” connects to the listening viewer on your machine. No muss, no fuss, only forward firewall ports on YOUR network, not having to worry about it on theirs and that’s the happy end to the story. (At least to that dillema).
All you need to do to make your custom ultravnc server is download the custom.zip from the Ultravnc SC site above, then make the necessary changes to the configuration file (what IP/domain name does the server try to connect to) altering logos and images are optional, as is letting the connection auto-launch. You can configure several connections to choose from if you do support from multiple locations. Once everything is configured zip it up and go to the form they have at this link, (current login is Userid: foo
Password:foobar) and upload your custom file, then you’ll get an exe download that you can then host on your website or some other easy to access location so you can direct users to easy remote tech support. I’ve tested this and even used it with another customer site already and find it to work VERY well.
Unfortunately it won’t help if they have basic network/browser problems, but some things require a first hand visit and likely always will. More in another post on getting ultravnc to work under linux.