Commands using watch (155)

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Copy a directory recursively without data/files

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Creat a tar file for backup info
Use tar command for a backup info with a date of creation

cat stdout of multiple commands
Concatenate the stdout of multiple commands.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Display IP : Count of failed login attempts
The lastb command presents you with the history of failed login attempts (stored in /var/log/btmp). The reference file is read/write by root only by default. This can be quite an exhaustive list with lots of bots hammering away at your machine. Sometimes it is more important to see the scale of things, or in this case the volume of failed logins tied to each source IP. The awk statement determines if the 3rd element is an IP address, and if so increments the running count of failed login attempts associated with it. When done it prints the IP and count. The sort statement sorts numerically (-n) by column 3 (-k 3), so you can see the most aggressive sources of login attempts. Note that the ':' character is the 2nd column, and that the -n and -k can be combined to -nk. Please be aware that the btmp file will contain every instance of a failed login unless explicitly rolled over. It should be safe to delete/archive this file after you've processed it.

Delete all files found in directory A from directory B
This command is useful if you accidentally untar or unzip an archive in a directory and you want to automatically remove the files. Just untar the files again in a subdirectory and then run the above command e.g. $ for file in ~/Desktop/temp/*; do rm ~/Desktop/`basename $file`; done

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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