Commands tagged nc (34)

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Convert all old SVN repositories in one directory to new format

Puts every word from a file into a new line
Basically it creates a typical word list file from any normal text.

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

shows history of logins on the server
outputs a history of logins on the server (top 10, when piped to 'head'); optional flags: '-a' put the hostname at the end of the line (good for long hostnames), '-i' post the IP instead of the hostname, '-F' put the full login and logout times, rather than short times.

port forwarding
pem file used by AWS servers for additional security

Double your disk read performance in a single command
(WARN) This will absolutely not work on all systems, unless you're running large, high speed, hardware RAID arrays. For example, systems using Dell PERC 5/i SAS/SATA arrays. If you have a hardware RAID array, try it. It certainly wont hurt. You may be can test the speed disk with some large file in your system, before and after using this: $ time dd if=/tmp/disk.iso of=/dev/null bs=256k To know the value of block device parameter known as readahead. $ blockdev --getra /dev/sdb And set the a value 1024, 2048, 4096, 8192, and maybe 16384... it really depends on the number of hard disks, their speed, your RAID controller, etc. (see sample)

concat multiple videos into one (and add an audio track)
This is an extract from a larger script which formats the video for DVD. The videos I use have no audio track so I need to add one. Tweak as you like...

Email yourself after a job is done
This is a two part command that comes in really handy if you're running commands that take longer than you're willing to wait. The commands are separated by the semicolon(;) The first command is whatever you're attempting to do. The second commands emails you after the job completes.

List the URLs of tabs of the frontmost Chrome window in OS X
This also works with Safari if you just change the application name. Replace $ window 1 with $ windows to list the URLs of tabs in all windows instead of only the frontmost window. This also includes titles: $ osascript -e{'set o to""','tell app"google chrome"','repeat with t in tabs of window 1','set o to o&url of t&"\n"&" "&title of t&"\n"',end,end}|sed \$d .

sort the output of the 'du' command by largest first, using human readable output.
In this case I'm just grabbing the next level of subdirectories (and same level regular files) with the --max-depth=1 flag. leaving out that flag will just give you finer resolution. Note that you have to use the -h switch with both 'du' and with 'sort.'


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