Questions[remote-access](ubuntu)

I need to automate desktop configuration via Puppet, virtual terminal or ssh.

Unfortunately, invocation of gsettings via ssh or virtual terminal gives:

gsettings set org.compiz.core:/org/compiz/profiles/unity/plugins/core/ hsize "4"

(process:29520): dconf-WARNING **: failed to commit changes to dconf: Cannot autolaunch D-Bus without X11 $DISPLAY

When I set the $DISPLAY with export DISPLAY=:0.0 it gives another error:

(process:29862): dconf-WARNING **: failed to commit changes to dconf: Could not connect: Connection refused

What can I do?

I need to access a postgresql database from a remote machine on a VPS at DigitalOcean running 12.10 and postgresql 9.1.

How do I do this? I noticed port 5432 is closed, how do I open this?

How do I copy files from my local to some remote server which hosts ssh on port other than default (22).

I usually connect to the server using

ssh [email protected] -p 2000

Now I need to copy files with scp

user@localbox:~$ scp ~/.ssh/id_rsa.pub [email protected]:~/.ssh/id_rsa_localbox.pub -p 2000

But this does not work.

I know Ubuntu comes with a "Remote Desktop" option that appears to be a straightforward VNC server, and I'm trying to understand the alternatives. Here are the possibilities I've heard about so far:

• VNC
• VNC + SSH Tunnelling
• NX Server, free edition
• FreeNX
• NeatX
• X2Go
• X11 Forwarding over SSH
• xrdp

I'm coming at this from a Windows user's perspective: To the best of my experience, RDP (aka Terminal Services) is a reasonably secure (barring mitm/server spoofing), efficient desktop sharing protocol with well-supported clients, that can be exposed to the internet when necessary without major fears of intrusion. To the best of my knowledge straight VNC is none of those things, which is where I get confused - why wouldn't a better desktop sharing technology be developed or used in the open-source world? I know VNC can be wrapped with SSH, but that seems beyond the reach of a casual user. X11 forwarding over SSH may be more or less efficient, I have no idea, but is definitely even more complicated, and doesn't (as far as I know) give you access to already-running stuff (no desktop sharing as such, just remote application running).

So, I'd like any feedback/preferences amongst these or any other "Free" desktop sharing options, using these criteria and/or any others:

1. Security (esp. for access across internet)
2. Efficiency (bandwidth usage, responsiveness, etc)
3. Free-ness, as in Speech (not sure where RDP or FreeNX lie for this)
4. Free-ness, as in Beer (are there any commercial solutions with usable dependable free offerings?)
5. Ease of use (server and client side)
6. Cross-OS Client availability
7. Cross-OS Server availability
8. Support for independent sessions and shared (and/or "Console") sessions
9. Ongoing support/maintenance/development

Thanks!

I'm setting up a server for backing up my desktop box remotely. I want to prevent remote password access to the server, permitting only users with private keys (AKA my desktop box) to access it. How can I block remote password access while allowing physical password access to the server?