Graphical Remote Control Desktops for Linux, part 3 - page 3

Final Steps For NXServer Setup

How one interfaces with a Linux firewall depends on whether one is using a firewall UI like Firestarter or manually edits iptables from within a firewall script. You might want to make a copy of your firewall script and call it something slightly different to make it possible for you to have a different firewall setup for when you're running on your local LAN and don't want even the possibility of outside access to your server and when you are elsewhere and want access to it yourself. Refer to your own firewall documentation for how to open whichever of these port ranges you decide to open.

Port Ranges in the default NX Server configuration

NX proxy port	5000 - 5200 *
X11 port	7000 - 7200 *
NX CUPS service port	3000 - 3200
NX SMB/CIFS share service port	4000 - 4200
NX Media service port	8000 - 8200
NX X11 auxiliary channel port	9000 - 9200

To use rdesktop RDP for Windows connections, open port 3389

The posts with asterisks are required, the rest are optional depending on what optional services you actually want to run. Open at least those asterisk ports on your server and any external firewall. If you want more services, open the corresponding ports.

With respect to printing, I generally would be working on a document via remote desktop, and I can print from it on the server without opening any new ports, if I give the print command on the remote desktop from within an application, it'll do that. If I need to print a server document on the client, I'll grab the file and open it locally in Open Office and print... or send it as a fax to a fax machine that's physically accessible to me. See comments on file transfers below.

For more specific information, go to NX Server Administrator's Guide, chapter 13.

File transfers between NX Server server and nxclient

SAMBA is supported, you'll need to set this up on the host and client and open the corresponding ports. SAMBA setup is beyond the scope of this document. While I have SAMBA set up on my home LAN, I'd rather leave the firewall ports closed and transfer files to/from client/server via a web-based "large file attachments" service like yousendit to make your files up to 2G in size available to client or server. SAMBA requires no special setup for NX Server, other than making sure the SAMBA ports used by Observer for encrypted file transmission (see firewall setup) are available from outside your computer or LAN.

Multimedia in NX Server

The only sound that can be remoted from the server is via the obsolete ESD audio server rather than the ALSA that's much more normal for modern Linux distributions. Since ESD does not work from within my current Debian/Lenny setup, I can't comment on how well this works. Hopefully, Nomachines will fix this problem in future releases. If this is important to you, here are setup instructions that will work with some multimedia programs, xmms for instance.

I recommend not bothering with remote desktop multimedia unless and until they get around to supporting ALSA by default. If you want to run multimedia on your client machine, grab the files on the server and run them on the client. The other upside of this is that you don't have to open the 5000-5200 port range in your firewall which NX Server defaults to.

Resources:

1. RDP clients information from Microsoft
2. Remote Desktop general information from MS
3. w9.x /2000 client setup
4. NoMachines support database / documentation links

As for user forums, if NoMachines has one, I haven't spotted it. In general, there are enough differences between how it works in various distros that you're best off looking for a distro-specific forum with a section or posts devoted to NX Server.