Written by Kai Lee
This report is a tutorial on how to set up a CSE ieng6 account on Visual Studio Code for UCSD students who will be taking CSE15L. In this tutorial, I will cover the following topics:
- Installing Visual Studio Code
- Connecting to your CSE ieng6 in VScode using ssh
- Basic remote operations
- Moving files with scp
- Setting an SSH key
- Optimizing remote connecting
Prerequisites for this tutorial:
- Know your ieng6 login credentials (you can look up your course specific account here)
- [Windows users only] Have OpenSSH installed.
For this course, our primary environment is Visual Studio Code. Download the latest version of VScode at their website. Select the version that matches your operating system, and follow the setup instructions of the installer.
Open VScode. The interface may look slightly different depending on the version and operating system, but the functionality should remain the same. Open up a new terminal by navigating to Terminal > New Terminal.
In the terminal, enter the following command, replacing your username in the placeholder:
ssh yourusername@ieng6.ucsd.edu
When you run this command, you'll get a message telling you that the authenticity of the host can't be established. This is normal when you are connecting remotely to a server for the first time, and type in 'yes' when it asks you if you still want to proceed. Enter your password when prompted. The terminal should then output information on the server and cluster status.
Notice that the text before your cursor in the terminal now displays [yourusername@ieng6-xyz]. This means that you are now connected remotely to the CSE server. Now, any commands that you run in the terminal won't run on your local machine, but rather on the machine that hosts the server that you are connected to. If you want to log out of the remote connection, press Ctrl+D, or enter the following command:
exit
The terminal should then confirm that your connection to the remote server has been closed.
Here are some basic terminal commands that you can run in order to navigate through your remote directory.
ls
pwd
mkdir
cd
ls lists all of the files in your current directory. In this case, the files WhereAmI.class and WhereAmI.class, and the folders perl5 and week1 are in the home directory of the remote computer.
pwd prints the working directory. In this case, the working directory is /home/linux/ieng6/cs15lwi22/cs15lwi22atz. Notice that because a remote connection is established, this is the working directory of the remote computer, rather than the directory of the local machine.
mkdir creates a folder in the current working directory. For example, calling mkdir examplefolder in the home directory creates a folder called examplefolder in the home directory. If we call ls again, examplefolder will be listed alongside the previously existing files.
cd navigates to a specific directory by following a path from your current working directory. From the previous example, cd examplefolder while will navigate the working directory to currentdirectory/examplefolder, where currentdirectory is a placeholder for your working directory. cd .. will navigate to the parent directory of your current directory, and cd ~ will navigate to your home directory.
You can use SCP command to copy files from your local machine to the remote machine. For example, in order to transfer the file HelloWorld.java from your local machine to the remote server, run the following command, and enter your password when prompted:
scp HelloWorld.java yourusername@ieng6.ucsd.edu:~/
Notice that this command is being run on the local machine, not through a remote connection, and that HelloWorld.java is in the same directory as the current working directory of the terminal.
Logging back into the remote server and listing out the file contents following the file copy will then display HelloWorld.java as a file in the remote server.
To run HelloWorld.java on the remote server, simply compile and run it normally while the remote connection is still established. Running ls again following this operation will show that HelloWorld.class was created during compilation, just as it would be if compiled locally.
It's important to note that if you already have a file with the same name in your copy destination, scp will overwrite it with the new file that you are copying, so watch out for any duplicate filenames.
There is a convenient way to bypass typing in a password every time you want to connect to or copy files to a remote server. By setting up an SSH key, which will be shared between your local machine and the remote server, you can eliminate the need to type your password every time you establish a remote connection.
On your local machine, run the following command:
ssh-keygen
Store your key in /Users/youruser/.ssh/id_rsa, where youruser is a placeholder for the username of your local machine. Then, login to your remote connection and create a .ssh directory using the following command:
mkdir.ssh
Log out of your remote connection, and copy the key from your local machine to the remote server using the following command:
scp /Users/youruser/.ssh/id_rsa.pub yourusername@ieng6.ucsd.edu:~/.ssh/authorized_keys
Now, try to login to your remote connection again. If you aren't prompted for a password, you've successfully set up your key.
There is an alternative way to run commands on a remote server without having to login first. With an SSH key pairing established between your local machine and remote server, it is possible to run a command from your local machine through the following command:
ssh yourusername@ieng6.ucsd.edu "your command in quotes"
For example, you can run ssh yourusername@ieng6.ucsd.edu javac HelloWorld.java to compile the java file HelloWorld on the remote machine.
In order to run multiple operations in one single line, seperate each command with a semicolon:
ssh yourusername@ieng6.ucsd.edu "command 1; command 2; command 3"
For example, the following command will compile and run HelloWorld.java on the remote server from the local machine in one line.
