Commands tagged ipv6 (7)

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mean color of an image
You can get the mean value for the colours in an image. Then you can determine, in general, how dark or bright is the image and run some other actions based on that. I'll recommend to readjust the brightness of the images using +sigmoidal-contrast option of imagemagick convert command.

Random Number Between 1 And X
If X is 5, it will about a number between 1 and 5 inclusive. This works in bash and zsh. If you want between 0 and 4, remove the +1.

Start dd and show progress every X seconds
Adjust "sleep X" to your needs. *NOTE: First sleep is required because bash doesn't have a "post-test" syntax (do XXX while).

Route outbound SMTP connections through a addtional IP address rather than your primary

Parse compressed apache error log file and show top errors
credit shall fall to this for non-gzipped version: https://gist.github.com/marcanuy/a08d5f2d9c19ba621399

Host cpu performance
Measure the cpu performance: In-case if the cpu is thermal throttling then you can find it using this command. Check the first line of the output. Example: Doing md5 for 3s on 16 size blocks: 11406892 md5's in 2.98s ? #(When cpu is not throttling) Doing md5 for 3s on 16 size blocks: 110692 md5's in 2.98s ?? #(When cpu is thermal throttling) Practical use case: Once we had cooling outage in data center which caused thermal throttling in some of the worker nodes. We used this tool to prove that some servers are not performing well because of the cpu thermal throttling.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

list files recursively by size

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"

Run netcat to server files of current folder


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