server names in linux

djgerbavore · 02-10-2005, 04:59 PM

hello,

i'm not sure were this thread should be at, but i put it in the newbie group anyways,

when i ssh into a linux server i just type in the server name, but when i want to connect to it with VNC (X11 Forwarding, i think that is what it is called), i first need to start the vnc server wiht

Code:

vncserver

which will return with same server name but with a colon followed by a number. My question is what is the colon and number after the server name for?

thanks,
djgerbavor3

cadkins · 02-10-2005, 05:10 PM

port number

djgerbavore · 02-10-2005, 05:15 PM

no, because it only goes up to 4, and you have to be root to access any port under 1024. I'm thinking it was to do with the order the servers or something.

michaelk · 02-10-2005, 05:23 PM

google lately?
http://www.uk.research.att.com/archive/vnc/xvnc.html
http://www.die.net/doc/linux/man/man1/xserver.1.html

cadkins · 02-10-2005, 05:56 PM

taken from the first link that michaelk posted above:

Quote:

Now, the VNC protocol normally uses port 59xx, where xx is the display number of the server. So a VNC server on a Windows machine, which normally uses display number 0, will listen on port 5900. Most Unix VNC servers will probably use display numbers 1,2, etc and so will be listening on ports 5901, 5902 and so forth. If you forward these ports to a remote machine, you can make the remote VNC server appear to be a server running on your local machine.

So, imagine you had a VNC server running as display :1 on machine snoopy, and you wanted a secure connection to it from your local machine. You could start the ssh session using:

ssh -L 5902:localhost:5901 snoopy

and any references to display :2 on your local machine would actually connect to display :1 on snoopy.