Commands by jjperezaguinaga (1)

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check open ports without netstat or lsof

Get list of servers with a specific port open
Change the -p argument for the port number. See "man nmap" for different ways to specify address ranges.

convert a line to a space

Spoof your wireless MAC address on OS X to 00:e2:e3:e4:e5:e6
If you want to check that the spoof worked, type the same command as earlier: $ifconfig en1 | grep ether Now you will see: $ether 00:e2:e3:e4:e5:e6 For the wired ethernet port: $sudo ifconfig en0 ether 00:e2:e3:e4:e5:e6

Change gnome-shell wallpaper

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

Identify long lines in a file
This command displays a list of lines that are longer than 72 characters. I use this command to identify those lines in my scripts and cut them short the way I like it.

Convert all MySQL tables and fields to UTF8
This loops through all tables and changes their collations to UTF8. You should backup beforehand though in case some data is lost in the process.

Downsample mp3s to 128K
This will lower the quality of mp3 files, but is necessary to play them on some mobile devices.

Show a Package Version on RPM based distributions
if you want to see all information about a package use: rpm -qi pkgname full list of querytags can be accessed by the command: rpm --querytags you can also customize the query format how ever you like with using more querytags together along with escape sequences in "man printf"! you can also use more than one package name. for example this command shows name and version in to columns: rpm -q --queryformat %-30{NAME}%{VERSION}\\n pkg1 pkg2


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