Commands for the wicked (109)

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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

To print a specific line from a file
You can get one specific line during any procedure. Very interesting to be used when you know what line you want.

copy ACL of one file to another using getfacl and setfacl
If you copy windows file in e.g. cygwin the ACL might miss on the copied file. With this command you can copy the ACL of an existing file to another. WARNING: Existing ACL will get lost.

move you up one directory quickly
Alias a single character 'b' to move to parent directory. Put it into your .bashrc or .profile file. Using "cd .." is one of the most repetitive sequence of characters you'll in the command line. Bring it down to two keys 'b' and 'enter'. It stands for "back" Also useful to have multiple: alias b='cd ../' alias bb='cd ../../' alias bbb='cd ../../../' alias bbbb='cd ../../../../'

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"

Query Wikipedia via console over DNS

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

runs a bash script in debugging mode

Ask for a password, the passwd-style
You can ask repeatedly for a non-blank password using this function: function read_password() { while [ ! -n "$USER_PASSWORD" ]; do read -s -p"Password: " USER_PASSWORD if [ ! -n "$USER_PASSWORD" ]; then echo "ERROR: You must specify a valid password, please try again" fi echo done } Also you can set a time out (in seconds) to write the password read -t 10 -s -p"Password: " USER_PASSWORD_VARIABLE if [ ! $? -eq 0 ]; then echo "Time out!" fi

dump the whole database


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