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´ve got a Server behind a firewall and the firewall only allows traffic through port 22. This server has both public and private addresses.
I´ve got also about 1K clients that I need to reverse shell to this server, and be able to choose one of them by id when I want that ssh reversed tunnel.
My goal is to make the clients connect to ssh server via port 22, and each one of this connections should be forwarded to localhost on port with the same id.
When I connect to the server with my laptop also via ssh, I would then ssh to localhost on the correct id and get the client shell.
Can someone provide me the good path to achieve this behaviour using bash, ssh and linux tools?
Note - I don´t want to use client.py and server.py cause most of my clients are android based and it could easily become a nightmare to install python on all of them.
The problem - it was solved using remote port forwarding:
ssh -R 21:localhost:8888 user#server
In this command the 8888 represents the terminal id. In order for this to work, had to add this line to my ssh conf:
GatewayPorts yes
I just installed the Bash Ubuntu on Windows 10 natively. When I try and acess a remote server I get ssh: connect to host HOSTNAME port 22: Connection refused
I have tried to find a solutions, but the solutions doesn't work.
This is what I have tried:
https://askubuntu.com/questions/59458/error-message-sudo-unable-to-resolve-host-user/733120#733120
When I could not acess /etx/hosts I tried this:
https://askubuntu.com/questions/326239/cannot-access-etc-hosts
After downloading gksudo to try and edit /etc/hosts I got this error message (gksudo:2601): Gtk-WARNING **: cannot open display:
Are u sure everything is correctly setup?
I just tried
ssh -T git#github.com
in my Bash on Ubuntu on Windows.
and it totally works Returning
Hi <usernamer>! You've successfully authenticated, but GitHub does not provide shell access.
Maybe you have some settings that prevent connections? for example in ~/.bashrc?
Maybe your server needs a different port? use ssh -p 2222 for that.
Up to yesterday, I have been connecting Tableau with R through Rserve on my localhost. Today, when I try to make the connection again, Tableau complained:
a error occurred during connection to localhost: 6311. No connection could be made because the target machine actively refused it
I doubled check Rserve is running. However, when I typed telnet localhost 6311 in cmd, no connection can be detected. It strikes me that something worked well for a few months suddenly stopped to function. I did installed RMySQL yesterday which seem to coincide with the timing, but is it possible? Any idea how to trouble shoot? Thanks.
Multiple things might be happening here.
check your netstat -ntlp output and see if its' listening on port 6311 and check if it's listening at 0.0.0.0:6311 or 127.0.0.1:6311. If you use the hostname rather than localhost it should be able to connect as long as the deamon is up. To connect using localhost from the same machine, stop Rserve and restart it as R CMD Rserve this will bind it to the loopback address, if you want it remotely accessible then you'll have to restart it using R CMD Rserve --RS-enable-remote
If you are using linux, you'll need to check your firewall and see if port 6311 is allowed .... ufw allow 6311 will do the trick.
Ben
This explanation may be helpful.
In my case, I was running through 'Rserve' and the configuration did not allow remote.
Initially invoke the Rserve using the command R CMD Rserve --RS-enable-remote from your server.Then call Rserve from your client machine.To test the connection try telnet IP port to the server which runs Rserve.This will do the trick.
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