CentOS 6 VNC Server denies connection - linux

I have set up tigervnc-server on my CentOS 6 machine following this guide. At first everything worked fine, I could connect to the server using TightVNC Viewer on my Windows machine. I left the session running in the background for a while. The server closed the inactive connection, which it also does for ssh or any other connections, so that's still normal. So I reconnected and everything was fine.
Then I decided to add a different user to the VNC users, as I was running my first connections from root. That's where it all broke. I couldn't connect to he server anymore, it always told me that the remote computer denied the connection. I made sure the server ports were open in iptables, tried to reinstall tigervnc-server, changing the config back to how it was before it broke and disabling the Windows Firewall. After reinstalling it, I was able to launch it without setting a vnc password, so it either saved it somehow from before or something broke entirely. None of my attempted fixes worked.

Turned out to be me not working on linux for over a year and I finally figured out I had to start the vnc server from the user I wanted it to run on.

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Far Manager NetBox SFTP can't connect to the linux server

I'm trying to connect to the RedHat Linux server through Far Manager 3.0.5800.0 x64 and NetBox plugin with SFTP. But it doesn't open the session as I expect it and doesn't exposure any errors. The connection screen blinks once and disappears, get me back to the NetBox: Stored sessions panel.
I CAN connect to that server through putty ssh, and it seems to be completely ok.
I CAN connect through Far Manager to THAT server as a different user also as a root user.
The problem was that I recently wrote in the .bashrc file some strings with "echo" command. And it seems to be after that the NetBox doesn't want to establish a session by that user.
So just inspect your .bashrc file and clean all echo commands.

Running GUI without need of remote desktop connection on-going

Build: Server with Ubuntu 18.04 in data center with Ubuntu Mate Desktop interface.
As I understand, any GUI app needs a display in which to function. I connect to the server via x2go to display the ubuntu mate interface.
Once connected, I have a scheduled cron job that launches a terminal, a GUI and some commands.
Everything works perfect as I have previously detected what display I'm using as a user and specify that to launch the terminal and the commands.
Problem: if I'm not connected via x2go client to the server and provide that display, I noticed today that the cron job didn't launch at the specific time (08:50), which was previous to my x2go client connection (09:23); it just launched when I did the x2go client connection from my desktop manually -- my understanding is that it didn't launch because there was not any available display.
I'm not technical enough to get more deep into this problem.
¿Is there anyway in which I can make the cron script function (i.e. that it launchs the terminal and the GUI) without the need of manually getting into my desktop and launching the remote desktop client (x2go)?
My ideas go for having another minimal setup in that data center or another that takes the advantages of being there and have a physical monitor to display constantly connected to the main server OR just manually entering the server via x2go every day.
EDIT: When I disconnect the x2go client session from the server, the launched GUI and etc perfectly maintains, without dissapearing because "I have terminated the session and eliminated the display".
Finally got it working with the great help of one of x2go founders (Oleksandr Shneyder) after understanding how x2go handles the sessions and the X server.
Sessions can suspended/hibernated, disconnected and terminated.
Suspended/hibernated: when "manually" or automatically the x2go server side suspends so that it saves resources.
Disconnected: when you exit the session window and the x2go client in your desktop/laptop.
Terminated: when you log out from the DE environment or issue the x2goterminate-session command in the terminal inside the session.
My x2go app was somehow entering into suspending mode in the server, causing that the display (50 in my case) in which the scheduled cronjob need to be run and launche the GUIs, "was not awaken" until I entered into the session via the
app. In that moment, the cronjob started executing.
To tell x2go server to not hibernate, I needed to change the X2GO_NXOPTIONS in /etc/x2go/x2goagent.options to X2GO_NXOPTIONS="sleep=0"
After this, everything functions perfectly in the server.
Hope it helps others.

Windows is showing rpc server is unavailable when connecting to a SAMBA AD hosted on debian

I have set up SAMBA to act as an AD DC and my machine connects to it fine but when I try to find the Active Directory tools from inside my windows machine I get the error 'naming information cannot be located because: the rpc server is unavailable'
I have no idea what thats bout and the few cases ive seen online deal in different situation not applicable to my case.
The problem can be on either the client or server machine.
Make sure Samba is listening on the right ports. RPC is on port 135. If you don't see Samba listening on port 135, then that's your problem.
Also make sure that, on your client Windows machine, the "TCP/IP NetBIOS Helper" service is running (in services.msc) and set to run automatically. If that was not running, then that's your problem.

Localhost not working and running on different network?

Overview
Win 10 pro, 64bit
static-server works from localhost
All other node.js servers stop working on localhost,127.0.0.1 and only works on 172.16.xxx.xxx host
From the source I can see that static-server host is 0.0.0.0 which is the same as mine. I run my server on 0.0.0.0 https://nodejs.org/api/net.html#net_server_listen_port_host_backlog_callback
All this happened suddenly on my windows machine and on several web apps with webpack. I installed windows again and the issue persists.
I use WebpackDevServer with host : 0.0.0.0
Details
I'm running on a brand new win 10 with some vpn installed.
So I have these 3 apps
webpack-app on host 0.0.0.0:9080
static-server on port 9080 (should be localhost as well)
webpack-app with react-create-app on port 3000
I start the webpack-app on port 9080 and I go to the browser and says "This site can’t be reached,localhost refused to connect." (I'm 100% sure is running on 9080 because all my webpack apps stop working at once)
I now start static-server and runs on port 9080, doesn't complain at all! Now I go to the browser and it opens the page on port 9080.
So now I think I'm running on 2 different networks. Here is how it looks in windows:
So now I look if somebody is listening to the port 9080 and I see this:
I turn off the static-server and it disappears. Means that the static-server correctly shows up there.
Also there is no other node.exe process over there. So where did my webpack-app ended up?
Now after some times something popups there on port 3000
Not sure why there are so many on the same port, I go to that url and it works. But doesn't work from localhost:3000.
What is going on? why it doesnt work from localhost anymore?
If you use the Windows Subsystem for Linux, especially WSL2, keep in mind that it runs in a Hyper-V virtual machine with a virtual NIC. In other words, it creates its own virtual network.
According to the WSL2 FAQs:
the new architecture uses virtualized networking components. This
means that in initial preview builds WSL 2 will behave more similarly
to a virtual machine, e.g: WSL 2 will have a different IP address than
the host machine. We are committed to making WSL 2 feel the same as
WSL 1, and that includes improving our networking story.
As a result, the development server will run at a different address than 127.0.0.1 (aka localhost). This is why a connection refused error is returned when calling localhost from the browser.
Here is a possible solution, as suggested by Microsoft.
Ran into the same issues as above. Cleared my browser data and cache, it worked like a charm!!
So very strangely after a few restarts it just works. My node.js server listens on 0.0.0.0 instead of 172.xxx.xxx.xxx. I'm really confused as why it works now and why was not working before. If somebody can figure out would be wonderful. Thanks everybody for the help.
Edit: Happened again and I fixed like this: I disabled all my docker and expressvpn apps to start on windows start and restarted my pc, now works.
Edit 2: Happened again and I fixed by closing express vpn and disabling my wifi. I only use the wired Ethernet cable. No need to restart this time.
I think something is going on with my windows machine. Not sure why there are to networks.

How Can I connect to Amazon Linux instance using Remote Desktop from Windows 7?

I created an EC2 Amazon Linux instance (yes, an amazon version of linux..)
it is launched but I can't connect using Remote Desktop...
am I trying to do something crazy here?
I got a message that Remote Computer is not available on the network
If you mean Windows RDP (Remote Desktop) that is your problem. Most likely you will need to use an SSH client to connect. I suggest Putty.
You should've received an SSH key when you setup your server. You will need to convert that key using PuttyGEN (same page as the Putty download) to convert it then use it with Putty to access the server.
Trying to walk you through the process of installing a GUI and VNC on the server is a bit much for here but give this video a shot. It seems pretty thorough and from skipping through it I saw no obvious errors in his process.
Try installing the vnc4server package. Then you can use a client such as TightVNC to connect from a Windows machine. You'll also need to open up port number 5900 in your firewall, which is the default for VNC.
You'll also have to have a desktop environment installed on your EC2 instance - by default you may only have the server packages which will not give you a GUI.
For your information, some folks posted remote desktop conf for EC2 instances.
http://activeintelligence.org/blog/archive/remote-graphical-linux-desktop-on-ec2/

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