A simple utility that can forward a remote port onto localhost via a jump server.
Only tested on forwarding ssh, Jupyter and PyCharm Professional version on a Windows PC as the localhost and CentOS 7 as the remote servers
Before using, make sure that key authentication is set correctly between localhost and jump server and jump server and target host. And the username of the jump server and target host should be the same.
For example, if you want to forward SSH service, the following commands should be run properly without input password:
# Connect jump server from localhost
localuser@localhost$ ssh remote_user@jump_server -p 22
# Connect target host from jump server
remote_user@jump_server$ ssh remote_user@target_host -p 22
# And the username in the jump server and target host should be the same
remote_user@target_hostIn this scenario, the target host can only be connected via a jump server.
Suppose that the IP of the jump server is 1.1.1.1,
the username of the jump server and the target host is the same, which is username,
the hostname of the target is cu01, which could be accessed on the jump server,
and the port of SSH on the target host is 22, and you want to map it as 10022 on localhost.
Just fill in the blanks as follows:
| Key | Value |
|---|---|
| Username: | username |
| Jump Server: | 1.1.1.1 |
| Target Host: | cu01 |
| Target Port: | 22 |
| Local Port: | 10022 |
And then, click the Connect button, and wait until the status becomes Connected, you can connect to the cu01 via ssh:
localuser@localhost$ ssh username@localhost -p 10022
username@cu01$ If you connect to different target hosts, ssh may warn you like this:
localuser@localhost$ ssh username@localhost -p 10022
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the ECDSA key sent by the remote host is
SHA256:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.
Please contact your system administrator.
Add correct host key in C:\\Users\\localuser/.ssh/known_hosts to get rid of this message.
Offending ECDSA key in C:\\Users\\localuser/.ssh/known_hosts:1
ECDSA host key for [localhost]:10022 has changed and you have requested strict checking.
Host key verification failed.You need to remove the line below in file ~/.ssh/known_hosts
[localhost]:10022 xxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Suppose that the IP of the jump server is 1.1.1.1,
the username of the jump server and the target host is the same, which is username,
the hostname of the target is gpu02, which could be accessed on the jump server,
the port of Jupyter would occur when running it, and you want to map it as 10022 on localhost.
First, make a configure file for Jupyter on your target host:
jupyter notebook --generate-configAnd edit ~/.jupyter/jupyter_notebook_config.py, make sure Jupyter would accept remote access:
c.NotebookApp.ip='0.0.0.0'Then, run jupyter notebook on the target host (suppose it is gpu02):
(base) [username@gpu02 ~]$ jupyter notebook
[W 2023-07-03 16:59:22.216 LabApp] 'ip' has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release.
[W 2023-07-03 16:59:22.216 LabApp] 'ip' has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release.
[W 2023-07-03 16:59:22.216 LabApp] 'ip' has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release.
[I 2023-07-03 16:59:22.225 LabApp] JupyterLab extension loaded from /home/username/anaconda3/lib/python3.9/site-packages/jupyterlab
[I 2023-07-03 16:59:22.225 LabApp] JupyterLab application directory is /home/username/anaconda3/share/jupyter/lab
[I 16:59:22.231 NotebookApp] Serving notebooks from local directory: /home/username
[I 16:59:22.231 NotebookApp] Jupyter Notebook 6.4.12 is running at:
[I 16:59:22.231 NotebookApp] http://gpu02:8888/?token=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
[I 16:59:22.231 NotebookApp] or http://127.0.0.1:8888/?token=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
[I 16:59:22.231 NotebookApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).
[C 16:59:22.239 NotebookApp]
To access the notebook, open this file in a browser:
file:///home/username/.local/share/jupyter/runtime/nbserver-xxxxx-open.html
Or copy and paste one of these URLs:
http://gpu02:8888/?token=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
or http://127.0.0.1:8888/?token=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxRemember the port (8888 in this case, or you can just set it in the ~/.jupyter/jupyter_notebook_config.py file), and fill in the blanks as follows:
| Key | Value |
|---|---|
| Username: | username |
| Jump Server: | 1.1.1.1 |
| Target Host: | gpu02 |
| Target Port: | 8888 |
| Local Port: | 10022 |
And then, click the Connect button, and wait until the status becomes Connected, you can browse the Jupyter on your localhost by visiting:
http://localhost:10022/?token=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Note that only PyCharm Professional Edition supports remote coding
Before setting on PyCharm, do the same thing as the SSH section.
After setting up a project, select File-Settings, and select Project-Python Interpreter on the left panel. Select Show all... in Python Interpreter on the right panel Add a new interpreter by clicking the plus sign "+"
Fill in the blanks as below, Port and Username are identical to the Local host and Username filled in our wizard.
Click Next, fill in the Interpreter and Sync folders as needed, then click Finish.
Right-click the project in the Project panel, and select Deployment-Upload To ....
PyCharm may work as you wish.