Commands by forcefsck

Commands by forcefsck (8)

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Find out the installation time of a linux system (when installed in a ext2/3/4 file system)

Find out the earliest installation time of a linux system by getting the / filesystem creation time. This example is only valid the os is installed on an ext2/3/4 filesystem.
This is sample output - yours may be different.
0

tune2fs -l $(df -P / | awk 'NR==2 {print $1}') | sed -n 's/^.*created: *//p'

forcefsck · 2012-05-31 12:12:35 0
encode/decode HTML entities

For reverse, there's asc2xml asc2xml < entitiesfile > utf8file They come as a part of the html-xml-utils debian package. PS. Tried to submit sample data, but the site autoconverted the non ascii to html entities. So a bit of imagination is needed. Show Sample Output
This is sample output - yours may be different.
```
$ echo "foo somegreekchars bar" | xml2asc
foo &#945;&#946;&#947;&#948; bar

$ echo "foo &#945;&#946;&#947;&#948; bar" | asc2xml 
foo somegreekchars bar
```
-3

xml2asc < inputfile > outputfile

forcefsck · 2011-02-23 12:22:18 1
Rename files in a directory in an edited list fashion

just an alternative to #7818 Show Sample Output
This is sample output - yours may be different.
```
Rename file: 1one
To: 1one.txt
`1one' -> `1one.txt'
Rename file: 2two
To: one plus one
`2two' -> `one plus one'
Rename file: 3three
To: 3three
Rename file: 4four
To: 2 x 2
`4four' -> `2 x 2'
Rename file: 5five
To: 5five.avi
`5five' -> `5five.avi'
```
0

exec 3<&0; ls -1N | while read a; do echo "Rename file: $a"; read -e -i "$a" -p "To: " b <&3 ; [ "$a" == "$b" ] || mv -vi "$a" "$b"; done

forcefsck · 2011-02-08 21:21:39 0
Display any udp/tcp connections by process name or by process id

Where COMMAND is the process(es) name. I prefer to get all states but you may add ESTABLISHED in the grep regex. lsof -c apache2 | egrep -o 'TCP.*ESTABLISHED.*$' -nP flags are optional and UDP is irrelevant for established connections Similar but using the process id: lsof -nP -p PID | egrep -o '(TCP|UDP).*$' Show Sample Output
This is sample output - yours may be different.
```
$ lsof -nP -c apache2 | egrep -o 'TCP.*$' | sort -u
TCP 192.168.0.2:443->192.168.0.136:3373 (ESTABLISHED)
TCP 192.168.0.2:443->192.168.0.137:11127 (ESTABLISHED)
TCP 192.168.0.2:443->192.168.0.137:11153 (ESTABLISHED)
TCP *:443 (LISTEN)
TCP *:80 (LISTEN)

$ lsof -p 17279|egrep -o '(TCP|UDP).*$'
TCP 127.0.0.1:32434 (LISTEN)
UDP *:32435 
```
0

lsof -nP -c COMMAND | egrep -o '(TCP|UDP).*$' | sort -u

forcefsck · 2011-01-25 12:04:13 0

network throughput test

On the machine acting like a server, run: iperf -s On the machine acting like a client, run: iperf -c ip.add.re.ss where ip.add.re.ss is the ip or hostname of the server. Show Sample Output

iperf -s

forcefsck · 2011-01-24 07:58:38 0

String to binary

Cool but useless. Show Sample Output
This is sample output - yours may be different.
```
perl -nle 'printf "%0*v8b\n"," ",$_;'
hello
01101000 01100101 01101100 01101100 01101111
world
01110111 01101111 01110010 01101100 01100100
!
00100001
```
6

perl -nle 'printf "%0*v8b\n"," ",$_;'

forcefsck · 2011-01-21 09:20:54 2
tcptraceroute alternative for udp packets

-T = traceroute -V = verbose --tr-stop = exit when target is reached -n = don't do reverse lookups (faster) -2 = udp -p 53 = destination port 53 (dns), change to your needs Useful when trying to debug a network with complex routing rules and/or multiple gateways.
This is sample output - yours may be different.
0

sudo hping3 -TV --tr-stop -n -2 -p 53 ns1.server.tld

forcefsck · 2011-01-14 10:12:37 0
Generate random valid mac addresses

Shorter and more straightforward. Also in perl: perl -e 'print join(":", map { sprintf "%0.2X",rand(256) }(1..6))."\n"'
This is sample output - yours may be different.
2

for i in {1..6}; do printf "%0.2X:" $[ $RANDOM % 0x100 ]; done | sed 's/:$/\n/'

forcefsck · 2010-12-07 19:26:58 0

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Convert all JPEG images to MP4

Source: http://superuser.com/a/624574

list block devices

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

Find usb device in realtime

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

convert video format to youtube flv format

Gathering all MAC's in your local network

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Convert mp3/wav file to asterisk ulaw for music on hold (moh)

Backup (archive) your Gmail IMAP folders.

Copies an entire hierarchy of mailboxes from the named POP3/IMAP/etc. source to the named destination. Mailboxes are created on the destination as needed. NOTE: The 'mailutil' is Washington's University 'mailutil' (apt-get install uw-mailutils). More examples $ mailutil transfer {imap.gmail.com/ssl/user=you@gmail.com}INBOX Gmail/ ; mailutil check imap.gmail.com/ssl/user=you@gmail.com}\[Gmail\]/Spam If you use the utility in the first, append -v|-d flag(s) to the end the commands above (man mailutil).

Real time duplication of Apache app traffic to a second server

This takes the stream created by apache requests containing jsp and funnels them to another server. I'm using this for simulating real time traffic. The nice command gives ssh maximum CPU cycles, awk & grep strip out everything served by apache. Putting parallel on curl is important because curl is synchronous and waits for the response. Yes, I thought about using wget but it didn't seem any easier. Also, if you figure out how to run this in the background let me know. Every time I background it it stops. If you have multiple front end servers just run multiple instances of this.

Efficient remote forensic disk acquisition gpg-crypted for multiple recipients

Acquires a bit-by-bit data image, gzip-compresses it on multiple cores (pigz) and encrypts the data for multiple recipients (gpg -e -r). It finally sends it off to a remote machine.

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