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sends a postscript file to a postscript printer using netcat

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"

Increase SCT of external USB disk enclosure to one hour.
So I had this 2TB Seagate external disk/USB enclosure which by default would spin-down its internal drive (it enters a standby mode) after four minutes of inactivity.. Spinning-up the inactive drive was an annoying delay when accessing files and also it severely interfered with NFS.. SCT stands for "Standby Condition Timer". To completely disable SCT: $ sdparm --clear STANDBY -6 /dev/sdb To return to original (default) SCT settings: $ sdparm -D -p 0x1a -6 /dev/sdb To verify the settings (before and after): $ sdparm -a /dev/sdb No need for vendor-provided MSWIN tools, etc.

Substrings a variable
substrings a variable starting at position. If no offset given prints rest of the line

View dmesg output in human readable format

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

encrypt whole line with ROT13 in vim

Get info about remote host ports and OS detection
Where < target > may be a single IP, a hostname or a subnet -sS TCP SYN scanning (also known as half-open, or stealth scanning) -P0 option allows you to switch off ICMP pings. -sV option enables version detection -O flag attempt to identify the remote operating system Other option: -A option enables both OS fingerprinting and version detection -v use -v twice for more verbosity. $ nmap -sS -P0 -A -v < target >

Create a local compressed tarball from remote host directory
This improves on #9892 by compressing the directory on the remote machine so that the amount of data transferred over the network is much smaller. The command uses ssh(1) to get to a remote host, uses tar(1) to archive and compress a remote directory, prints the result to STDOUT, which is written to a local file. In other words, we are archiving and compressing a remote directory to our local box.

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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