Commands using tr (339)

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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

continuously check size of files or directories

Print all /etc/passwd lines with duplicated uid
Prints all the lines in /etc/passwd belonging to users with a duplicated uid. It also adds the hostname to the beginning of the line. It's been tested in AIX, Solaris and Linux.

Fix for error perl: warning: Setting locale failed.
Fix for ubuntu error: perl: warning: Setting locale failed. perl: warning: Please check that your locale settings: LANGUAGE = "en_GB:en", LC_ALL = (unset), LANG = "en_GB.UTF-8" are supported and installed on your system. perl: warning: Falling back to the standard locale ("C"). locale: Cannot set LC_CTYPE to default locale: No such file or directory locale: Cannot set LC_MESSAGES to default locale: No such file or directory locale: Cannot set LC_ALL to default locale: No such file or directory

check open ports without netstat or lsof

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)

Tune your guitar from the command line.
This command, taken from play's manual page, plays a synthesized guitar tone for each of the strings on a standard tuned guitar. The command "play" is a part of the package "sox".

find out how many days since given date
You can also do this for seconds, minutes, hours, etc... Can't use dates before the epoch, though.

Monitor a file with tail with timestamps added
Should be a bit more portable since echo -e/n and date's -Ins are not.

Synchronize date and time with a server over ssh
Shorter, easier to remember version of cmd#7636 NTP is better, but there are situations where it can't be used. In those cases, you can do this to sync the local time to a server.


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