Commands by gnuyoga (5)

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Anti Syn Ddos
Ddos syn attack

Prints new content of files
Useful to e.g. keep an eye on several logfiles.

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"

erase content from a cdrw

Using a single sudo to run multiple && arguments
This will also work with bash instead of sh shell sudo bash -c 'apt update -y && apt upgrade -y'

Find files that are older than x days
Find files that are older than x days in the working directory and list them. This will recurse all the sub-directories inside the working directory. By changing the value for -mtime, you can adjust the time and by replacing the ls command with, say, rm, you can remove those files if you wish to.

Analyze awk fields
translate and number lines is simpler and you use tr to choose your delimiter (eg for csv files)

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

shell bash iterate number range with for loop

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials


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