Commands by opexxx

Commands by opexxx (34)

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16 Character Random Password

This snippet will produce an alpha-numeric 16 character password Show Sample Output
This is sample output - yours may be different.
```
sll_IBZS8dL4H8bQ
```
0

< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c${1:-16};echo;

opexxx · 2014-04-07 10:07:22 8
for ssh uptime
This is sample output - yours may be different.
0

for k in `seq -w 1 50` ; do ssh 192.168.100.$k uptime ; done

opexxx · 2013-11-26 13:23:15 7
20char long alpahnumeric "password"

20characters long alpahnumeric "password" Show Sample Output
This is sample output - yours may be different.
```
5698d846bfe078d67aef43fc0eebe4233401ad23
```
-1

head -c20 /dev/urandom | xxd -ps

opexxx · 2013-07-16 10:14:21 9
psgrepp

grep по ps aux
This is sample output - yours may be different.
1

ps aux | grep $(echo $1 | sed "s/^\(.\)/[\1]/g")

opexxx · 2013-07-16 10:10:51 7
show directory three

show directory three
This is sample output - yours may be different.
-4

find . -type d | sed -e "s/[^-][^\/]*\// |/g" -e "s/|\([^ ]\)/|-\1/"

opexxx · 2013-07-16 10:08:34 8
count the number of times you match a substring in a larger text file
This is sample output - yours may be different.
-3

sed ?s/[sub_str]/[sub_str]\n/g? [text_file] | wc -l

opexxx · 2013-03-28 12:00:56 5
Clear the screen and list file

Clear the screen and list file
This is sample output - yours may be different.
0

alias cls='clear;ls'

opexxx · 2013-03-19 12:18:47 13
Find top 5 big files

Find top 5 big files
This is sample output - yours may be different.
-3

find . -type f -exec ls -s {} \; | sort -n -r | head -5

opexxx · 2013-03-19 12:16:24 6
Add an "alert" alias for long running commands

Add an "alert" alias for long running commands
This is sample output - yours may be different.
0

alias alert='notify-send --urgency=low -i "$([ $? = 0 ] && echo terminal || echo error)" "$(history|tail -n1|sed -e '\''s/^\s*[0-9]\+\s*//;s/[;&|]\s*alert$//'\'')"'

opexxx · 2013-03-19 11:45:47 6
identify active network connections
This is sample output - yours may be different.
0

lsof -i -P +c 0 +M | grep -i "$1"

opexxx · 2013-03-19 10:42:15 5
Open Port Check

Open Port Check
This is sample output - yours may be different.
-1

netstat -an | grep --color -i -E 'listen|listening'

opexxx · 2013-03-19 08:53:47 7
cymru malware check
This is sample output - yours may be different.
2

md5sum filename | ncat hash.cymru.com 43

opexxx · 2013-03-18 14:24:12 6
Remove blank lines
This is sample output - yours may be different.
2

sed '/^$/d'

opexxx · 2013-03-18 14:16:42 5
Compress blank lines
This is sample output - yours may be different.
6

cat -s

opexxx · 2013-03-18 14:15:48 12
Capitalize the first letter of every word
This is sample output - yours may be different.
1

sed "s/\b\(.\)/\u\1/g"

opexxx · 2013-03-18 14:15:13 6
Extract all IPs from a file
This is sample output - yours may be different.
0

grep -E '([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})' -o tmp

opexxx · 2013-03-18 14:12:22 6
speedtest

alias speedtest='wget --output-document=/dev/null http://speedtest.wdc01.softlayer.com/downloads/test500.zip'
This is sample output - yours may be different.
1

wget --output-document=/dev/null http://speedtest.wdc01.softlayer.com/downloads/test500.zip

opexxx · 2013-03-15 13:25:07 8
my ip
This is sample output - yours may be different.
0

curl ip.appspot.com

opexxx · 2013-03-15 13:23:19 5
Generate password
This is sample output - yours may be different.
1

tr -dc 'A-Za-z0-9!@#$%^&*' < /dev/urandom | fold -w 12 | head -n 1

opexxx · 2013-03-15 13:20:32 84
system update
This is sample output - yours may be different.
-12

sudo apt-get update && sudo apt-get upgrade && sudo apt-get clean

opexxx · 2013-03-15 13:19:26 11
Using column to format a directory listing

Using column to format a directory listing Show Sample Output
This is sample output - yours may be different.
```
PERMISSIONS  LINKS  OWNER  GROUP  SIZE        MONTH  DAY  HH:MM  PROG-NAME
-rw-r--r--   1      root   root   61167       12.    Nov  2008   120253snmp.log
-rw-r--r--   1      root   root   246313      6.     M?r  2008   120_43.log
-rw-r--r--   1      root   root   22947       14.    Mai  09:42  120discovery.log
```
3

(printf "PERMISSIONS LINKS OWNER GROUP SIZE MONTH DAY HH:MM PROG-NAME\n" \ ; ls -l | sed 1d) | column -t

opexxx · 2009-10-08 11:53:38 5
Transforms a file to all uppercase.

Transforms a file to all uppercase.
This is sample output - yours may be different.
6

tr '[:lower:]' '[:upper:]' <"$1"

opexxx · 2009-10-08 11:34:07 3
Outputs a 10-digit random number
This is sample output - yours may be different.
2

head -c4 /dev/urandom | od -N4 -tu4 | sed -ne '1s/.* //p'

opexxx · 2009-10-08 11:27:20 4
mysql DB size
This is sample output - yours may be different.
2

mysql -u root -pPasswort -e 'select table_schema,round(sum(data_length+index_length)/1024/1024,4) from information_schema.tables group by table_schema;'

opexxx · 2009-10-06 07:10:49 5
Bashbuiltin printf
This is sample output - yours may be different.
0

cat file.txt | while read line; do printf "%7.2f -> %7.2f\n" $line; done

opexxx · 2009-10-06 07:09:23 7
1 2 >

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Detect illegal access to kernel space, potentially useful for Meltdown detection

Based on capsule8 agent examples, not rigorously tested

Remove all but one specific file

Change the window title of your xterm

If you are using an xterm emulation capable terminal emulator, such as PuTTY or xterm on Linux desktop, this command will replace the title of that terminal window. I know it is not nice to have seventeen terminals on your desktop with title PuTTY, you can not tell which one is connected to which server and doing what. Even though the string between the quotes is typed as literals, it needs a little more finesse to make it work. Here is how it is done key-by-key: echo "( ctrl-v then ctrl-[ )0;Enter_Title_String_Here( ctrl-v then ctrl-g )"( enter ) ctrl-v : means hold down ctrl key and hit v at the same time like you are pasting in windoze ; also please don't type the parentheses, i.e., ( and )

Write comments to your history.

A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Copy a directory recursively without data/files

Find Duplicate Files (based on MD5 hash)

Calculates md5 sum of files. sort (required for uniq to work). uniq based on only the hash. use cut ro remove the hash from the result.

Redirect incoming traffic to SSH, from a port of your choosing

Stuck behind a restrictive firewall at work, but really jonesing to putty home to your linux box for some colossal cave? Goodness knows I was...but the firewall at work blocked all outbound connections except for ports 80 and 443. (Those were wide open for outbound connections.) So now I putty over port 443 and have my linux box redirect it to port 22 (the SSH port) before it routes it internally. So, my specific command would be: $iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 22 Note that I use -A to append this command to the end of the chain. You could replace that with -I to insert it at the beginning (or at a specific rulenum). My linux box is running slackware, with a kernel from circa 2001. Hopefully the mechanics of iptables haven't changed since then. The command is untested under any other distros or less outdated kernels. Of course, the command should be easy enough to adapt to whatever service on your linux box you're trying to reach by changing the numbers (and possibly changing tcp to udp, or whatever). Between putty and psftp, however, I'm good to go for hours of time-killing.

Compress and store the image of a disk over the network

Create an image of "device" and send it to another machine through the network ("target" and "port" sets the ip and port the stream will be sent to), outputting a progress bar On the machine that will receive, compress and store the file, use: $nc -l -p | 7z a -si -m0=lzma2 -mx=9 -ms=on Optionally, add the -v4g switch at the end of the line in order to split the file every 4 gigabytes (or set another size: accepted suffixes are k, m and g). The file will be compressed using 7z format, lzma2 algorithm, with maximum compression level and solid file activated. The compression stage will be executed on the machine which will store the image. It was planned this way because the processor on that machine was faster, and being on a gigabit network, transfering the uncompressed image wasn't much of a problem.

Backup files incremental with rsync to a NTFS-Partition

This will backup the _contents_ of /media/SOURCE to /media/TARGET where TARGET is formatted with ntfs. The --modify-window lets rsync ignore the less accurate timestamps of NTFS.

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