More than once I find myself opening a file with vim, pasting the contents, saving the file, and then going back to bash to do some magic with it. With this line, you simply run the command, paste in the contents that you want, and end with EOF to end the loop. In this case, I paste in a list of URLs, but only want to grab those that contain the string 'https':
I had an issue recently where I had to debug why a request to a website was taking such a long time. After a bit of searching around, I found the following bit of code:
Multiple times I've had to extract certificates from PFX files, and have them converted to PEM. This little script does everything:
To convert a Putty public SSH key to an OpenSSH public key, run:
I encountered an issue today where someone requested that we keep the 10 newest backup files, while the rest of them (the oldest) were deleted. So I made this little script:
#!/bin/bash
FILE_DIR="/home/jorge/backup/"
NUMBER_OF_FILES="$(ls -t $FILE_DIR | wc -l)"
RETAIN=10
if [ "$NUMBER_OF_FILES" -ge "$RETAIN" ]; then
cd $FILE_DIR
ls -t | sed -e "1,$RETAIN d" | xargs rm -f
fi
This can be modified to match with any type of file or filename.
I have been working with Linux for years, and I've always used screen when working in the terminal. I even wrote a small introduction to screen over 10 years ago.
So you can imagine my surprise when I at a very late point found out about tmux. It has completely changed the way I work, and boy do I love it.
To delete all files in a directory, between two dates, use the find command:
To scan for newly added/modified disks, run the following command as root:
I am hopefully going to take the second half of my RHCE exam this year, which is EX294. I have taken inspiration from and , and have decided to provide my own answers and explanations as I myself prepare for the exam.
I’ve also only used 4 VM’s in total, 1 controller and 3 nodes, and not 4 nodes as the practice exam suggests.
Here are the tips that I’ve found helpful so far:
I was helping a colleague of mine set up VPN, with the client Viscosity to be specific, on macOS. During the process of setting it up, we noticed that remains of an old license, from another place, was still there. When she tried connecting to one of our remote servers, she got the following error:
This copy of Viscosity is registered using a license that does not allow connections to one or more of the remote servers for this connection. Please contact your VPN Provider for further details.
Tried searching for options to unregister the old license, but there was nothing visible in the GUI. I finally found a solution though, but it needs to be done in the terminal.
Then press Enter. Now start Viscosity again, and it should no longer give you that error. If your trial period has ended, you will have to enter a new valid license.