PuTTY Fatal Error
 

Hello,

I download putty.exe on my Windows 10 machine. I filled out the PuTTY configuration using my IP address for the "Specify your connection by host name or IP address". I left the "Load, save or delete a stored session" blank. I then pressed "Open" and got the message:

PuTTY Fatal Error
Network error: Connection refused

What can I do?

Thanks.

Epcgirl

Make sure the box you want to connect to accepts incoming connections on port 22, if it is behind a router then router has to be configured to forward the port.

Hi Emerson,

Thanks for taking the time to answer my post. I don't like to reveal the extent of my ignorance, but I actually didn't understand what you said. I am using a Motorola Surfboard SBG6580 modem & Wi-Fi router and getting internet access through Xfinity. I am using Ubuntu through VMware to learn UNIX and am trying to complete the step of actually connecting to UNIX. Perhaps you can point me to the resource where I can find out what the "box" is that you are speaking of? You seemed to distinguish it from the modem.

Thanks.

Epcgirl

OK, lets clarify. You are not making connection to a remote host. You are attempting SSH connection to a virtual machine from host operating system. Correct?

Hi Emerson,

I tried to download putty.exe within the VMware, but it didn't download or rather, the .exe file wouldn't execute. I then downloaded it on the Windows 10 environment and the PuTTY Configuration window opened as can be seen in the UNIX book I'm following along on. I input the IP address as requested. I am attempting an SSH connection but I don't know who with. I assume the ISP given that I input the IP address and since the PuTTY Configuration is within the native Windows environment, and not through the VMware.

Hope this makes sense.

Epcgirl

You need to set up a computer (can be virtual) to accept SSH connections. Then, using the IP address of this computer, you can log on over SSH.

Your trying to establish a ssh connection between windows and your Ubuntu VMware guest. As stated you need to enter the IP address of your Ubuntu virtual machine. There are several ways to find the IP address if you do not know how. In addition you have to start the ssh server on Ubuntu before a connection will work.

What Ubuntu version are you running?

In addition to making sure the proper ports are open, make sure that sshd (the ssh server program) is running on the target machine. How to do that can vary slightly from distro to distro.

Hi Emerson, michaelk and frankbell,

Thank you all for your replies.

@michaelk -- thanks for explaining that what is required is to establish connection between Windows and Ubuntu VMware guest. I did enter the IP address of the virtual machine into the PuTTY configuration in windows, and that's when I get the error. How do I start the SSH server on Ubuntu 14.04?

@Emerson, @frankbell -- these ports that you are speaking of - I will look them up and find out what they are. By target machine, you mean the host machine, right?

Thanks.

Epcgirl

So network services like a web, ftp or ssh server communicate over different ports. A port is a number from 0-65535. Think of your computer as huge apartment complex, its IP address is the street address and the port is the apartment number. In order for the client to talk to the server you need both. In your case PuTTy is the client and sshd is the ssh server running on the Ubuntu VM. Most services have a default number i.e web server is 80, ssh is 22, ftp 21 and so on.

A firewall is a system that monitors incoming and outgoing traffic and protects your computer from the outside world. If it was running they typically block all incoming connections and allow outgoing so you can get your email and browse the internet etc. And in your case block PuTTy from connecting to the Ubuntu box. Port 22 must be open to allow ssh connections. I suspect it is off but we will find out.

What Unix book are you following?

Before we can turn on ssh we need to know if its installed.

Lets open a terminal window by pressing ctrl+alt+t or you can go to Applications Accessories Terminal from the menu.
sudo apt-get install openssh-server (use your user password)
sudo apt-get install openssh-client (use your user password)

To start the server
sudo service ssh start

Now you should be able to login using ssh as your self.
ssh localhost (user your user password)

If that works type exit to quit ssh

Run the command
sudo iptables -L

if you see the following then your firewall is off
We might still have a networking issue but try again to connect using PuTTy.

yo tambien tengo ese problema y no se que hacer de lo q me dieron no me lo ha solucionado q hago

Per the rules, all posts should be in English.

Hi michaelk,

THANKS! I did as you suggested, the firewall was off. Now I get the PuTTY Security Alert Window - server's host key is not cached in the registry. No guarantee that the server is the computer that I think it is.

Is this normal? Should I proceed?

The book that I am using is Visual Quickstart Guide UNIX Third Ed. by Deborah S. Ray and Eric J. Ray.

Epcgirl

This is normal at first login.

Yes and yes. select ok or continue ,can't remember what the button name is and you should be connected.