VNC problems

[ZootHornRollo]

Hi,

i have a machine set up as a headless audio player connected to my hifi.

I normally use VNC to connect to it and control it but i am getting an error.

vncviewer: ConnectToTcpAddr: connect: Connection refused
Unable to connect to VNC server

Any ideas what i can do resolve this without connecting up a monitor?

I have no way to reboot without holding the power button in for 5 secs.

[ZootHornRollo]

The IP address is right as it shows up on my router as an attached device and i can ping it.

[ZootHornRollo]

i cannot ping the vnc port (5900). i get this message.

ping: unknown host 192.168.0.3:5900

[superprash2003]

try accessing via hostname instead of ip, could be that the ip 192.168.0.3 of the machine has changed..

[scorp123]

i cannot ping the vnc port (5900)

Of course not. "Ping" always uses the same port: 7 (icmp). You cannot "ping" ports, only hosts. If you want to check what ports are open on a remote machine you should use port-scanning tools such as "nmap" ... you will find this tool in the repositories (e.g. via Synaptic) and plenty of tutorials via Google. And don't you ever "nmap" foreign IP addresses!! Some people might interpret that network scan as an attack ("nmap" is one of those tools which is used by "both sides", good and bad!) so you please make sure you only use "nmap" against your own computers, OK?

If "vncviewer" says it cannot connect then it's most likely that either the IP address of the host has changed or that the VNC server running there has crashed for some reason (this can happen) and isn't there any longer.

So you should check:

- can you ping that PC and are you 100% sure that the IP address is correct?
- what does "nmap" say which ports are remotely open or not open?

If 5900 is closed then the VNC server has died for some reason and you should "ssh" into your remote PC and start it again.

[ZootHornRollo]

many thanks for a very informative reply.

i will give it a go tomorrow morning.

cheers.

[xc3ll]

Try ssh'ing into the box and make sure vncserver is running.

Do a
$ps aux | grep vncserver

If vncserver is running, it'll show up.

[ZootHornRollo]

after a bit of googling i have discovered that i must have SSH client on this machine (installed on default installation) but do not have ssh-server on my audio machine as i have never knowingly added it.

I have never used it.

I only got the machine set up properly a few days ago and was planning just to use vnc to control it. i have been testing the vnc/wifi connection for over a month with no problems so i took the monitor away this morning after backing up all the audio files on the HD to DVD. Just typical that it was today i encountered the first issue regarding remote controlling it only hours after taking away the monitor!!

I'll need to get the monitor out again (big 19" CRT monster!!!) and install ssh and then learn all about that!!!

should i install the blacklist too?

[xc3ll]

Installing ssh server is super easy, although there's a few steps you should take to keep it secure. Here's a guide on getting ssh up and running:

https://help.ubuntu.com/6.06/ubuntu/...sh-server.html

Along with a guide on ssh keys:

http://kimmo.suominen.com/docs/ssh/

If you set up ssh correctly and have a good strong password (big like Pepsi can), you shouldn't have to worry about using a blacklist.

In case you have no idea what SSH is, its pretty much an application that will give you a secure remote terminal. As long as you can ssh into a box, you can pretty much solve any problems that you might be experiencing. It will also allow you to secure VNC (which I also highly suggest. You can either port forward or use the -via option in vncviewer)

[ZootHornRollo]

Try ssh'ing into the box and make sure vncserver is running.

Do a
$ps aux | grep vncserver

If vncserver is running, it'll show up.

i have installed SSH server but still can't really make much use of it.

how do i run the above command? do i run it on the server or on the client?