I ssh into a server with the following:
ssh -g -L5912:server:5912 user#host
It goes through, and I can access my files on the other server through the command line (meaning I can connect to the server, it is my vnc viewer that is failing!) but when I try to open my vnc viewer (RealVNC) and connect to localhost:12 i get the following error message in the vnc viewer application:
The connection closed unexpectedly.
Additionally in the original command line shell i get:
channel 3: open failed: connect failed: No route to host
I've tried switching to different ports and even checked out other posts on the same error message but the problem is i don't really understand them... ssh tunnels are still relatively new to me so i don't really know what im doing. Any help would be greatly appreciated. Thanks!
You're trying to setup a port forwarding, this may fail because of many reasons:
SSH port forwarding not enabled in the host
Check SSH server in the host if AllowTcpForwarding is enabled:
$ grep AllowTcpForwarding /etc/ssh/sshd_config
AllowTcpForwarding yes
Typically, it's commented out. Uncomment and restart the sshd.
No connection between the host and server over port 5912
SSH to the host and try:
$ telnet server 5912
Connected to server.
Escape character is '^]'.
Finally, does the server listen on 5912?
Similarly, as above, but from the server - go there and try telnet server 5912.
Best regards,
Jarek
In my case it was the port forwarding rule I had set in Putty.
Please make sure you enter the correct hostname when defining the rule in Putty. I changed
localhost:5903
with
myserver:5903
and it worked...
I launched a new AWS EC2 Ubuntu Server t2.micro instance via the AWS console. I was able to successfully connect to the instance a single time using ssh on macOS Sierra 10.12.3:
$ ssh -i ./ubuntu-server-2-17-2017.pem ubuntu#ec2-55-555-555-555.compute-1.amazonaws.com
However, when I try to connect a second time, I get a time out error:
$ ssh -i ./ubuntu-server-2-17-2017.pem ubuntu#ec2-55-555-555-555.compute-1.amazonaws.com
ssh: connect to host ec2-55-555-555-555.compute-1.amazonaws.com port 22: Operation timed out
How can I resolve this issue?
The first thing to check is that the IP address associated with the instance is still the same.
The other thing to look at, then, is the security group to see if your IP address (which maybe changed) is still allowed.
My lab runs RStudio on a server. A couple weeks ago, from my cousin's house, I successfully ssh'd into the server and pulled up the server-side RStudio through my local Firefox browser. Now when I try to access the server RStudio from home (via my own router), it doesn't work. I need help troubleshooting, and I'm guessing it's some problem on the router. I'm running Mac OSX 10.6.8. No idea what the university server's running, but I don't think it's a server-side problem.
Here's how it worked the first time I did it, at my cousin's house: first, I VPN into the university network; then I call SSH with port forwarding; then I open a Firefox browser, connect to my localhost port, and it opens up RStudio on the server side which I can access through my local browser window.
Here's the problem I'm having right now when I try to log-in from my home network:
I can make the VPN connection successfully. I can also set up SSH successfully with this command:
ssh -v -L 8783:localhost:8783 myacct#server.com
Here are the last several lines of the verbose output from the successful ssh command:
debug1: Authentication succeeded (password).
debug1: Local connections to LOCALHOST:8783 forwarded to remote address localhost:8783
debug1: Local forwarding listening on 127.0.0.1 port 8783.
debug1: channel 0: new [port listener]
debug1: Local forwarding listening on ::1 port 8783.
debug1: channel 1: new [port listener]
debug1: channel 2: new [client-session]
debug1: Entering interactive session.
Last login: Mon Sep 2 04:02:40 2013 from vpnipaddress
So I think I'm still succeeding at the VPN and SSH stage (though I don't know why it says my last login was Sep 2 when I've logged in a few times since then).
Next, I open Firefox, and I type localhost:8783, and instead of getting an RStudio server app through my browser window, I get the following errors:
In the Firefox browser window, it says: Server not found, Firefox can't find the server at www.localhost.com, Check the address for typing errors etc.
In the terminal window, it says:
debug1: Connection to port 8783 forwarding to localhost port 8783 requested.
debug1: channel 3: new [direct-tcpip]
channel 3: open failed: connect failed: Connection refused
debug1: channel 3: free: direct-tcpip: listening port 8783 for localhost port 8783, connect from 127.0.0.1 port 50420, nchannels 4
I'm not sure what I've got wrong. I haven't changed anything on my laptop since my last successful connection. I'm on my own router (instead of my cousin's), so maybe I need to mess with the firewall? I already allowed ports 22 and 8783 to come through the firewall to my laptop (I'm not even sure I needed to do that though). Help?
ssh -v -L 8783:localhost:8783 myacct#server.com
...
channel 3: open failed: connect failed: Connection refused
When you connect to port 8783 on your local system, that connection is tunneled through your ssh link to the ssh server on server.com. From there, the ssh server makes TCP connection to localhost port 8783 and relays data between the tunneled connection and the connection to target of the tunnel.
The "connection refused" error is coming from the ssh server on server.com when it tries to make the TCP connection to the target of the tunnel. "Connection refused" means that a connection attempt was rejected. The simplest explanation for the rejection is that, on server.com, there's nothing listening for connections on localhost port 8783. In other words, the server software that you were trying to tunnel to isn't running, or else it is running but it's not listening on that port.
Posting this to help someone.
Symptom:
channel 2: open failed: connect failed: Connection refused
debug1: channel 2: free: direct-tcpip:
listening port 8890 for 169.254.76.1 port 8890,
connect from ::1 port 52337 to ::1 port 8890, nchannels 8
My scenario; i had to use the remote server as a bastion host to connect elsewhere. Final Destination/Target: 169.254.76.1, port 8890. Through intermediary server with public ip: ec2-54-162-180-7.compute-1.amazonaws.com
SSH local port forwarding command:
ssh -i ~/keys/dev.tst -vnNT -L :8890:169.254.76.1:8890
glue#ec2-54-162-180-7.compute-1.amazonaws.com
What the problem was:
There was no service bound on port 8890 in the target host. i had forgotten to start the service.
How did i trouble shoot:
SSH into bastion host and then do curl.
Hope this helps.
Note: localhost is the hostname for an address using the local (loopback) network interface, and 127.0.0.1 is its IP in the IPv4 network standard (it's ::1 in IPv6). 0.0.0.0 is the IPv4 standard "current network" IP address.
I experienced this error with a Docker setup. I had a Docker container running on an external server, and I'd (correctly) mapped its ports out as 127.0.0.1:9232:9232. By port-forwarding ssh remote -L 9232:127.0.0.1:9232, I'd expected to be able to communicate with the remote server's port 9232 as if it were my own local port.
It turned out that the Docker container was internally running its process on 127.0.0.1:9232 rather than 0.0.0.0:9232, and so even though I'd specified the container's port-mappings correctly, they weren't on the correct interface for being mapped out.
In my case, it worked after running the vncserver on linux.
Entered this on linux command line : sudo ssh -L 5901:localhost:5901 -i <ssh_private_key> <username>#<public-IP-address>
Type there vncserver
Go to VncViewer application and connect using localhost:5901
I used to meet the similar problem because 'localhost' was not available on server when it restarted network service, e.g. 'ifdown -a' but followed by only 'ifup -eo1'. Besides server is not listening to the port, you can also check 'localhost' is available or not.
ps: Post it just hope someone who has the similar problem may benefit.
I had this problem when I wanted to make a vnc connection via a tunnel.
But the vncserver was not running.
I solved it by opening the channel on the remote machine with vncserver :3.
In my case, it worked after checking the correct IP address of the user credentials
previously I was using the wrong IP of the server
ssh -NfL 127.0.0.1:8084:127.0.0.1:8888 user#ip_address_of_server
after correcting it, works fine.
Encountered with the same error.
In my case, I found the problem was in the config file of jupyter.
Let's say there are 3 computers named A, B, and C, and A can access B but can't access C; B can access C.
To access jupyter-notebook service of C from A, first I established ssh tunnel from A to C through B, then I access jupyter-notebook by typing localhost:port_number, then I got the error.
Finally the problem was solved by writing the "c.NotebookApp.ip = '0.0.0.0'" in jupyter-notebook's config file, where '0.0.0.0' allows the access of other IPs.
Hope someone in a similar situation may benefit.
I had the same error when I was trying to tunnel my mlflow ui over ssh to view remotely. As mentioned in the first answer, the error arises because nothing on the server is listening for the port. This, for me, is because I forgot to start the mlflow app on my remote machine! So in general – make sure the app you're trying to access remotely is running.
Just replace localhost with 127.0.0.1.
(The answer is based on answers of other people on this page.)
This means the remote vm is not listening to current port i solved this by adding the port in the vm server
I am trying to run putty on Windows 7.
I need to run some SSH commands to upgrade Magento. Every time putty gives me this fatal error:
network error: connection refused
I have even tried to use it through winSCP. Note that putty is running fine on my client's side, but for me it's giving me that error every time.
I tried using port 22, 23 and a few others without success. I have also tried with Windows Firewall both enabled and disabled.
Thank you.
Install open-ssh or ssh in target Linux machine solved my problem .
Use below commands:
sudo apt install ssh
sudo systemctl status ssh
sudo systemctl enable ssh
The following are the list of possibilities of this error:
1) Common cause is - Your IP is blocked or not whitelisted in the server which can be done by editing the file at /etc/csf/csf.conf
2) Disable the windows firewall settings and check..
The above two things should work in most of the cases
3) This is very unusual and when the above two options fails it is very difficult to find the solution
In this case the traceroute to the server host or IP works usually but putty fails
port 22 looks normal and working but connection fails and restarting SSH (service ssh restart) also does not work
reboot or restart the server but still fails
Adding IP in firewalls or whitelisting the local IP may not workout
This case generally happens when the server is migrated or new server. IP of the old server might be whitelisted locally, but don't have port 22 open, or some other local filtering is occurring for this new IP but not the old server IP..
In this case you need to change the port to some 522 or 530 some unusual port will help in sorting it out.. The same port you have to use for the SFTP connection also .. where as FTP connections works normally..
or you have to whitelist the IP locally or open the TCP in and out to port 22 if you want to use the port 22..
I am a newbie trying out SSH. The scenario is I have 2 machines - Windows 7 PC(Desktop) and a VMWare machine (Windows 7). Cygwin installed on both. I am trying to connect the VMWare machine to the desktop. I have installed the OpenSSH server on Desktop server. I verified it is running, using netstat.
I modified the Windows firewall, by adding to the Inbound Rules to allow connections for port 22.
My problem is I am unable to connect from the VMWare machine.
$ ssh -v user_name#my_machine
OpenSSH_5.5p1, OpenSSL 0.9.8q 2 Dec 2010
debug1: Connecting to my_machine port 22.
debug1: connect to address my_machine port 22: Connection refused
ssh: connect to host my_machine port 22: Connection refused
What am I doing wrong? What are my options to configure? Any links or answers would be helpful.
Thank you.
WM
Open your command prompt and run the following command:
ssh -v Your_User_Name#Your_IP_Address
If response is:
OpenSSH_for_Windows_7.7p1, LibreSSL 2.6.5
debug1: Connecting to Your_IP_Address port 22.
debug1: connect to address Your_IP_Address port 22: Connection refused
ssh: connect to host Your_IP_Address port 22: Connection refused
Then go to the Windows Service called OpenSSH SSH Server is started and running, it is set to manual start as default so it will not be running unless you have started it.
Now run above command again. SSH command will connect to the user.
You should make sure that my_machine allows inbound connection. Check the firewall....
(if you can run this command locally - but not from the other machine it might be that case).
If the ssh server on the Desktop is accessible in the localhost then try this
Desktop <- Desktop Firewall <- VM Firewall <- VM
Try shutting down the firewalls in between one by one to check where the issue starts after then configure accordingly. Remember that the Desktop Firewall rules should be inbound and the VM Firewall is outbound