I have a spring boot application, and I run a performance test on it, using Gatling.
The issue is that after a few requests where everything works OK, the server returns connection refused and no other requests are working.
Gatling log looks like this:
---- Requests ------------------------------------------------------------------
> Global (OK=14 KO=1001 )
> POST /template (OK=13 KO=938 )
> PUT /feedback (OK=1 KO=63 )
---- Errors --------------------------------------------------------------------
> j.n.ConnectException: Connection refused: no further informati 577 (57,64%)
on
> j.i.IOException: Premature close 240 (23,98%)
> j.n.c.ClosedChannelException 184 (18,38%)
When I create a manual request using curl, returns:
$ curl https://localhost:8087
curl: (7) Failed to connect to localhost port 8087: Connection refused
If I connect to docker and do the request:
$ docker exec -it web /bin/bash
root#794f9e808f14:/# curl https://localhost:8443
curl: (60) SSL certificate problem: unable to get local issuer certificate
More details here: https://curl.se/docs/sslcerts.html
SSL handshake failed, as expected, but this means that the server is up an running.
The port is mapped in docker:
$ docker port web
8443/tcp -> 0.0.0.0:8087
8443/tcp -> :::8087
After restart, all thing happen again.
I'm using docker on a WSL Ubuntu. Not sure if this matters too much. What can I do to make this connection more stable?
I can connect to the first server with key but cannot connet to the second server jumping with the first server. I doubt it is a bug on MacOS because I can jump to the seceond server with command line. Is there ANYONE knows what happened here?
Here is the config:
Host comp
HostName xx.xx.xxx.xxx
User xxxx
Port 22
IdentityFile ***************
Host local
HostName 127.0.0.1
Port ****
User xxxx
ProxyCommand ssh -q -x -W %h:%p comp
IdentityFile ***************
Here is the error information:
[19:55:48.660] Log Level: 2
[19:55:48.662] remote-ssh#0.55.0
[19:55:48.662] darwin x64
[19:55:48.663] SSH Resolver called for "ssh-remote+localhost", attempt 1
[19:55:48.663] SSH Resolver called for host: localhost
[19:55:48.663] Setting up SSH remote "localhost"
[19:55:48.669] Acquiring local install lock: /var/folders/5q/****************_tr0000gn/T/vscode-remote-ssh-localhost-install.lock
[19:55:48.713] Looking for existing server data file at /Users/gy/Library/Application Support/Code/User/globalStorage/ms-vscode-remote.remote-ssh/vscode-ssh-host-localhost-************************************-0.55.0/data.json
[19:55:48.742] Using commit id "***********************************" and quality "stable" for server
[19:55:48.743] Install and start server if needed
[19:55:48.779] Checking ssh with "ssh -V"
[19:55:48.854] > OpenSSH_8.1p1, LibreSSL 2.7.3
[19:55:48.860] Using SSH config file "/Users/gy/.ssh/config/vscodeconfig"
[19:55:48.861] askpass server listening on /var/folders/5q/******************_tr0000gn/T/vscode-ssh-askpass-**********************************.sock
[19:55:48.862] Spawning local server with {"ipcHandlePath":"/var/folders/5q/**************_tr0000gn/T/vscode-ssh-askpass-********************************.sock","sshCommand":"ssh","sshArgs":["-v","-T","-D","54815","-o","ConnectTimeout=15","-F","/Users/gy/.ssh/config/vscodeconfig","localhost"],"dataFilePath":"/Users/gy/Library/Application Support/Code/User/globalStorage/ms-vscode-remote.remote-ssh/vscode-ssh-host-localhost-*********************************-0.55.0/data.json"}
[19:55:48.862] Local server env: {"DISPLAY":"1","ELECTRON_RUN_AS_NODE":"1","SSH_ASKPASS":"/Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/local-server/askpass.sh","VSCODE_SSH_ASKPASS_NODE":"/Applications/Visual Studio Code.app/Contents/Frameworks/Code Helper (Renderer).app/Contents/MacOS/Code Helper (Renderer)","VSCODE_SSH_ASKPASS_MAIN":"/Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/askpass-main.js","VSCODE_SSH_ASKPASS_HANDLE":"/var/folders/5q/********************_tr0000gn/T/vscode-ssh-askpass-**********************************.sock"}
[19:55:48.871] Spawned 34492
[19:55:48.987] > local-server> Spawned ssh: 34493
[19:55:49.008] stderr> OpenSSH_8.1p1, LibreSSL 2.7.3
[19:55:50.129] stderr> kex_exchange_identification: Connection closed by remote host
[19:55:50.131] > local-server> ssh child died, shutting down
[19:55:50.136] Local server exit: 0
[19:55:50.136] Received install output: OpenSSH_8.1p1, LibreSSL 2.7.3
kex_exchange_identification: Connection closed by remote host
[19:55:50.137] Stopped parsing output early. Remaining text: OpenSSH_8.1p1, LibreSSL 2.7.3kex_exchange_identification: Connection closed by remote host
[19:55:50.137] Failed to parse remote port from server output
[19:55:50.141] Resolver error: Error:
at Function.Create (/Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/extension.js:1:130564)
at Object.t.handleInstallOutput (/Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/extension.js:1:127671)
at Object.t.tryInstallWithLocalServer (/Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/extension.js:127:102339)
at processTicksAndRejections (internal/process/task_queues.js:94:5)
at async /Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/extension.js:127:104310
at async Object.t.withShowDetailsEvent (/Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/extension.js:127:109845)
at async /Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/extension.js:127:100912
at async R (/Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/extension.js:127:97702)
at async Object.t.resolveWithLocalServer (/Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/extension.js:127:100561)
at async Object.t.resolve (/Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/extension.js:127:107840)
at async /Users/gy/.vscode/extensions/ms-vscode-remote.remote-ssh-0.55.0/out/extension.js:127:141955
[19:55:50.143] ------
Could someone enlighten me on the reason for the problem or on a possible solution ? Thanks !
I have the similar problem.
Later it disappears after I turn off the agent server.
Maybe you can try this.
I'm using Robot Framework to test network issues and servers. I'm on a windows environment.
Right now, I'm in need to test if a certain service is available on localhost on a certain port. I could use netstat together with the Process library to figure out if the desired service is running on the designated port, but this seems to be a bit clumsy.
What might be a best suited Robot Framework library, to obtain the desired information?
You can do this by using robot framework SSHLibrary (http://robotframework.org/SSHLibrary/SSHLibrary.html)
Below example shows how to create ssh tunnel for port 8082 in the 192.168.10.10 host and map the 8082 port to 8083 in the local machine
*** Settings ***
Documentation This example demonstrates executing a command on a remote machine
... and getting its output.
...
... Notice how connections are handled as part of the suite setup and
... teardown. This saves some time when executing several test cases.
Library SSHLibrary
Suite Setup Open Connection And Log In
Suite Teardown Close All Connections
*** Variables ***
${HOST} 192.168.10.10
${USERNAME} username
${PASSWORD} Password
*** Test Cases ***
Execute Command And Verify Output
[Documentation] Execute Command can be used to run commands on the remote machine.
... The keyword returns the standard output by default.
${output}= Execute Command echo Hello SSHLibrary!
Should Be Equal ${output} Hello SSHLibrary!
*** Keywords ***
Open Connection And Log In
Open Connection ${HOST}
Login ${USERNAME} ${PASSWORD}
create local ssh tunnel 8083 ${HOST} 8082 #source_port host_ip destination_port
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...
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