Commands by hkyeakley

Commands by hkyeakley (2)

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Remove blank lines from a file

To save the result, redirect the output to another file. grep -v "^$" file1 > file2
This is sample output - yours may be different.
-1

grep -v "^$" file

hkyeakley · 2009-02-19 18:11:58 3
Quick glance at who's been using your system recently

This command takes the output of the 'last' command, removes empty lines, gets just the first field ($USERNAME), sort the $USERNAMES in reverse order and then gives a summary count of unique matches. Show Sample Output
This is sample output - yours may be different.
```
1 wtmp
      2 reboot
     31 oracle
     15 jsmith
    142 jdoe
      3 root
```
15

last | grep -v "^$" | awk '{ print $1 }' | sort -nr | uniq -c

hkyeakley · 2009-02-18 16:38:59 1

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Search for a string inside all files in the current directory

ack seeks for , list all found files and display everything in nice colors. Look for it in http://betterthangrep.com/

remap Caps_Lock to Escape

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"

Print diagram of user/groups

Parses /etc/group to "dot" format and pases it to "display" (imagemagick) to show a usefull diagram of users and groups (don't show empty groups).

List the Sizes of Folders and Directories

Generate a random password 30 characters long

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

list block devices

Shows all block devices in a tree with descruptions of what they are.

Serve current directory tree at http://$HOSTNAME:8000/

List pr. command in megabytes sum of deleted files that are still in use and therefore consumes diskspace

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