IT

IDS: Snort on Raspberry PI

Fabio Bombardi,

In questo articolo vedremo come installare un software per l’intrusion detection della nostra rete sul nostro Raspberry Pi.

Per prima cosa ci serve un sistema operativo opportuno da installare sul nostro Raspberry PI. Per questo tipo di applicazione ho scelto Kali linux il successore della distro linux BackTrack, famosissima nel campo della sicurezza IT.

Scarichiamo quindi l’immagine per processore ARM dal sito ufficiale:

https://www.kali.org/downloads/

che ci rimanda per il porting su Raspberry PI al sito

https://www.offensive-security.com/kali-linux-vmware-arm-image-download/

In base alla versione di Raspberry PI che avete scaricate la iso opportuna.

Io ho il Raspberry PI versione B e quindi ho scelto la distro Raspberry Pi A/B+

Una volta scaricato occorre copiare l’immagine sull’SD card che volete utilizzare sul Raspberry con i comandi che trovare anche sull’articolo in questo blog relativo al backup e ripristino del vostro Raspberry PI.

Riporto qui i passi fatti sul mio MacBook Air:

Fabios-MacBook-Air:~ shadowsheep$ diskutil list
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *121.3 GB   disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            75.0 GB    disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3
   4:       Microsoft Basic Data BOOTCAMP                45.5 GB    disk0s4
/dev/disk1
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:     FDisk_partition_scheme                        *8.1 GB     disk1
   1:                 DOS_FAT_32 CHIAVINA                8.1 GB     disk1s1
Fabios-MacBook-Air:~ shadowsheep$ diskutil unmountDisk /dev/disk1
Unmount of all volumes on disk1 was successful
Fabios-MacBook-Air:~ shadowsheep$ cd Downloads/
Fabios-MacBook-Air:Downloads shadowsheep$ xz -d kali-1.1.0-rpi.img.xz
Fabios-MacBook-Air:Downloads shadowsheep$ sudo dd bs=1m if=kali-1.1.0-rpi.img of=/dev/disk1
Password:
3000+0 records in
3000+0 records out
3145728000 bytes transferred in 2055.895717 secs (1530101 bytes/sec)
Fabios-MacBook-Air:Downloads shadowsheep$

Il comando dd ci metterà un po’ a terminare. Una volta terminato avremo la nostra immagine installata sull’SD.
Una volta installata la nostra distro possiamo inseriamo l’SD card sul Raspberry e accendiamolo.

In questo tutorial io accederò al nostro Raspberry Pi solamente tramite SSH.

Ma prima occorre verificare che la dietro abbia ottenuto un IP valido e inoltre voglio ricreare una signature SSH differente da quella standard.

Per utilizzare il mio nuovo Raspberry Pi con Kali quindi attacchiamo una tastiera USB e un monitor che abbia l’ingresso HDMI.

L’utente root ha password “toor”. Cambiamola subito con “passwd”

root@kali:~# passwd
Enter new UNIX password:

Rigeneriamo quindi anche le chiave per l’SSH server

root@kali:~# cd /etc/ssh
root@kali:/etc/ssh# mkdir ssh_default_keys
root@kali:/etc/ssh# mv ssh_host* ssh_default_keys/
root@kali:/etc/ssh# dpkg-reconfigure openssh-server
Creating SSH2 RSA key; this may take some time ...
Creating SSH2 DSA key; this may take some time ...
Creating SSH2 ECDSA key; this may take some time ...
[ ok ] Restarting OpenBSD Secure Shell server: sshd.
root@kali:/etc/ssh#

Da adesso possiamo collegarci tramite SSH.

Non avendo installato una versione di linux apposta per il Raspberry ci viene a mancare la comoda utility raspi-config. Andiamo quindi ad aggiungerla manualmente alla nostra installazione di Kali linux.

wget http://archive.raspberrypi.org/debian/pool/main/r/raspi-config/raspi-config_20121028_all.deb
wget http://ftp.acc.umu.se/mirror/cdimage/snapshot/Debian/pool/main/l/lua5.1/lua5.1_5.1.5-4_armel.deb
wget http://http.us.debian.org/debian/pool/main/t/triggerhappy/triggerhappy_0.3.4-2_armel.deb
dpkg -i triggerhappy_0.3.4-2_armel.deb
dpkg -i lua5.1_5.1.5-4_armel.deb
dpkg -i raspi-config_20121028_all.deb

Una volta installato lanciamolo per espandere il nostro filesystem. Infatti l’immagine di Kali linux installata è stata fatta per essere ospitata da una SD da 4GB e quindi se ne abbiamo una più grande (come nel mio caso 8GB) dobbiamo appropriarci dello spazio mancante! 🙂

root@kali:~# df
Filesystem     1K-blocks    Used Available Use% Mounted on
rootfs           2896624 1570816   1158952  58% /
/dev/root        2896624 1570816   1158952  58% /
devtmpfs           89804       0     89804   0% /dev
tmpfs              18796     488     18308   3% /run
tmpfs               5120       0      5120   0% /run/lock
tmpfs              37580       0     37580   0% /run/shm

Screen Shot 2015-03-22 at 11.48.27 Screen Shot 2015-03-22 at 11.48.47

Facciamo il reboot del sistema e dopo averlo fatto ecco apparire tutti i nostri GB!

root@kali:~# df
Filesystem     1K-blocks    Used Available Use% Mounted on
rootfs           7633328 1573136   5701036  22% /
/dev/root        7633328 1573136   5701036  22% /
devtmpfs           89804       0     89804   0% /dev
tmpfs              18796     496     18300   3% /run
tmpfs               5120       0      5120   0% /run/lock
tmpfs              37580       0     37580   0% /run/shm

A questo punto installiamo tutti i pacchetti che la distribuzione Kali linux ci mette a disposizione per l’IT security:

root@kali:~# apt-get update && apt-cache search kali-linux
Get:1 http://http.kali.org kali Release.gpg [836 B]
Get:2 http://security.kali.org kali/updates Release.gpg [836 B]
Get:3 http://http.kali.org kali Release [21.1 kB]     
Get:4 http://security.kali.org kali/updates Release [11.0 kB]
Get:5 http://http.kali.org kali/main Sources [7570 kB]  
Ign http://security.kali.org kali/updates/contrib Translation-en            
Ign http://http.kali.org kali/contrib Translation-en                         
Ign http://security.kali.org kali/updates/main Translation-en                
Ign http://security.kali.org kali/updates/non-free Translation-en             
Ign http://http.kali.org kali/main Translation-en                              
Ign http://http.kali.org kali/non-free Translation-en                          
Get:6 http://security.kali.org kali/updates/main Sources [146 kB]              
Get:7 http://security.kali.org kali/updates/contrib Sources [20 B]             
Get:8 http://security.kali.org kali/updates/non-free Sources [20 B]            
Get:9 http://http.kali.org kali/non-free Sources [118 kB]                      
Get:10 http://security.kali.org kali/updates/main armel Packages [277 kB]      
Get:11 http://http.kali.org kali/contrib Sources [56.9 kB]                     
Hit http://security.kali.org kali/updates/contrib armel Packages               
Get:12 http://http.kali.org kali/main armel Packages [8284 kB]                 
Hit http://security.kali.org kali/updates/non-free armel Packages              
Get:13 http://http.kali.org kali/non-free armel Packages [91.2 kB]             
Hit http://http.kali.org kali/contrib armel Packages                           
Fetched 16.6 MB in 1min 55s (143 kB/s)                                         
Reading package lists... Done
kali-linux - Kali Linux base system
kali-linux-all - Kali Linux - all packages
kali-linux-forensic - Kali Linux forensic tools
kali-linux-full - Kali Linux complete system
kali-linux-gpu - Kali Linux GPU tools
kali-linux-pwtools - Kali Linux password cracking tools
kali-linux-rfid - Kali Linux RFID tools
kali-linux-sdr - Kali Linux SDR tools
kali-linux-top10 - Kali Linux Top 10 tools
kali-linux-voip - Kali Linux VoIP tools
kali-linux-web - Kali Linux webapp assessment tools
kali-linux-wireless - Kali Linux wireless tools
root@kali:~# apt-get install kali-linux-full

Andate a fare una bella passeggiata, prendete un buon aperitivo, incontrate degli amici in attesa che il sistema si installi completamente…

E infine installiamo Snort:

root@kali:~# apt-get install snort

Se voltete installare l’ultima versione di Snort a partire dai sorgenti ufficiali sul sito potete seguire le istruzioni sul sito snort.org:

Se la configurazione del daq vi da errore perché manca la libreria libpcap allora dovete installarla:

apt-get install libpcap-dev

Al termine della compilazione e installazione del daq dovreste vedere un report simile a questo.

----------------------------------------------------------------------
Libraries have been installed in:
   /usr/local/lib/daq

If you ever happen to want to link against installed libraries
in a given directory, LIBDIR, you must either use libtool, and
specify the full pathname of the library, or use the `-LLIBDIR'
flag during linking and do at least one of the following:
   - add LIBDIR to the `LD_LIBRARY_PATH' environment variable
     during execution
   - add LIBDIR to the `LD_RUN_PATH' environment variable
     during linking
   - use the `-Wl,-rpath -Wl,LIBDIR' linker flag
   - have your system administrator add LIBDIR to `/etc/ld.so.conf'

See any operating system documentation about shared libraries for
more information, such as the ld(1) and ld.so(8) manual pages.
----------------------------------------------------------------------

Se la configurazione di snort vi da errore perché non trova le librerie libpcre e libante allora installatele con il comando:

apt-get install libpcre3 libpcre3-dev
apt-get install libdumbnet-dev

Al termine invece di snort dovreste vedere un report simile a questo assieme a molte altre cose (tante!)

----------------------------------------------------------------------
Libraries have been installed in:
   /usr/local/lib/snort/dynamic_output

If you ever happen to want to link against installed libraries
in a given directory, LIBDIR, you must either use libtool, and
specify the full pathname of the library, or use the `-LLIBDIR'
flag during linking and do at least one of the following:
   - add LIBDIR to the `LD_LIBRARY_PATH' environment variable
     during execution
   - add LIBDIR to the `LD_RUN_PATH' environment variable
     during linking
   - use the `-Wl,-rpath -Wl,LIBDIR' linker flag
   - have your system administrator add LIBDIR to `/etc/ld.so.conf'

See any operating system documentation about shared libraries for
more information, such as the ld(1) and ld.so(8) manual pages.
----------------------------------------------------------------------

A questo punto avete il vostro Snort installato!

root@kali:~/tmp/snort-2.9.7.2# snort -V

   ,,_     -*> Snort! <*-
  o"  )~   Version 2.9.7.2 GRE (Build 177) 
   ''''    By Martin Roesch & The Snort Team: http://www.snort.org/contact#team
           Copyright (C) 2014 Cisco and/or its affiliates. All rights reserved.
           Copyright (C) 1998-2013 Sourcefire, Inc., et al.
           Using libpcap version 1.3.0
           Using PCRE version: 8.30 2012-02-04
           Using ZLIB version: 1.2.7
IDS: Snort on Raspberry PI

A little of Bash Shell

Fabio Bombardi

Tables are inspired at tables you can find in:
O’Really, Learning the bash Shell, 3rd Edition By Cameron Newham

Utilities

The most wanted utilities in unix should surely be the following ones:

Utility

Purpose

cat

grep

sort

cut

sed

rt

awk

Copy input to output

Search for string in the input

Sort lines in the input

Extract columns from input

Perform editing operation on input

Translate characters in the input to other characters

Full-featured text processing language with a syntax reminiscent of C

For example the grep command is very useful to fing text inside files like shown below:

grep –Hnr “Fabio Bombardi” .

This command search for the string “Fabio Bombardi” in all files, recursively (-r) , starting from the current directory (.), showing the line number (-n) where this string is located in the found file.

I/O Redirectors and pipelines

Redirector

Purpose

<

>

Redirect the right side argument as input of the left side argument

Redirect the output of the left side argument to the left right side argument

For example if your cp command is broken you can use the cat command in the following way:

cat < file1 > file2

This behaves like the command 

cp file1 file2

Redirector

Purpose

cmd1 | cmd2

Redirect the output of the left side command cmd1 to the input of the right side command cmd2

For example you can use the command

ls -l | more

to send the list the file in the current directory as the input of the more command.

It’s possible to use the I/O redirection in conjunction with pipelines like in the following example:

cut –d: -f1 < /etc/passwd | sort

this command extract the first field (f1) in the file /etc/passwd, where fields are separated by colons (-d:) and sort that first field showing it on the output.

The above redirectors are the most used. But you may found a plethora of other useful redirectors, above all for a system programmer, like those listed in the table below.

Redirector

Purpose

> file

< file

>> file

>| file

n>| file

<> file

n <> file

<< label

n> file

n< file

n>> file

n>&

n<&

n>&m

n<&m

&> file

<&-

>&-

n>&-

n<&-

Direct standard output to file

Take standard input from file

Direct standard output to file; append to file if it already exists

Force standard output to file even if noclobber is set

Force output to file from file descriptor n even if noclobber is set

Use file as both input and output for file descriptor n

Use file as both input and output for file descriptor n

Here-document; see text

Direct file descriptor n to file

Take file descriptor n from file

Direct file descriptor n to file; append to file if it already exists

Duplicate standard output to file descriptor n

Duplicate standard input from file descriptor n

File descriptor n is made to be a copy of the output file descriptor m

File descriptor n is made to be a copy of the input file descriptor m

Directs standard output and standard error to file

Close the standard input

Close the standard output

Close the output from file descriptor n

Close the input from file descriptor ni

For example if you want to redirect both the standard error and the standard output of the ls command to a logfile you could type what follows:

ls > logfile 2>&1

This will redirect the standard error (2) in the same place where the standard output (1) is directed. Since standard output is redirected to logfile hence also the standard error will be redirected there too.

If you want you could get the same result also with the following commnd:

ls &> logfile

Special characters and quoting

Special characters

Character

Purpose

~

#

$

&

*

(

)

\

|

[

]

{

}

;

‘

“

<

>

/

?

!

Home directory

Comment

Variable expression

Background job

String wildcar

Start subshell

End subshell

Quote next character

Pipe

Start character-set wildcard

End Character-set wildcard

Smart command block

End command block

Shell command separator

Strong quote

Weak quote

Input redirect

Ouput redirect

Pathname directory separator

Single-character wildcard

Pipeline logical NOT

Quoting

When you want to use special character without their special meaning you have to use quoting. If you surround a string of characters with single quotation marks (or quotes), you strip all characters within the quotes of any special meaning they might have.

For example if you want to print in standard output the string “2*3 > 5 is an invalid inequality” you have to type the following command:

echo ‘2 * 3 > 5 is an invalid inequality’

Otherwise you will get a file named 5 containing the list of 2, all the files in the current directory, and the string “3 is an invalid inequality”!

Another way to change the meaning of a character is to precede it with a backslash (\). This is called backslash-escaping the character.

Quoting and find

The most useful use of the quoting is along with the command find.

If you want to find all the character with .c extension you have to act like below:

find . -name ‘*.c’

Control key setting

To know your control-key setting you can type

stty all

And you will get something like that:

erase kill werase rprnt flush lnext susp intr quit stop eof

^? ^U ^W ^R ^O ^V ^Z/^Y ^C ^\ ^S/^Q ^D

Or type 

stty -a

If your Unix version derives from System III or System V (this include also Linux) to obtain a similar list of control-key.

History Expansion

In order to see the list of the history c-shell command you can type the following command:

fc -l

Command

Purpose

!

!!

!n

!-n

!string

!?string?

^string1^string2

Start a history substitution

Refers to the last command

Refers to command line n

Refers to current command line minus n

Refers to the most recent command starting with string

Refers to the most recent command containing string. The ending ? is optional.

Repeat the last command, replacing string1 with string2

Tabella 1 – event designator

For example, if your last command was the whoami command, you are able to retype it only by typing 

!!

It’s also passible to refer to certain words in a previous command by the use of a word designator

Designator

Purpose

0

n

^

$

%

x-y

*

x*
x-

The zeroth (first) word in a line

The nth word in a line

The first argument (the second word)

The last argument in a line

The word matched by the most recent ?string search

A range of words from x to y. –y is synonymous with 0-y.

All words but the zeroth (fist). Synonymous with 1-$. If there is only one word on the line, an empty string is returned.

Synonymous with x-$

The words from x to the second last word

Tabella 2 – word designator

The word designator follows the event designator, separated by a colon. It’s possible, for example, repeat the previous command without arguments by typing

!!:0

Or it’s possible to repeat the previous command with different arguments

!!:0 arg0 arg1 arg2

For example if you type 

!!:0 --version

(in this case the same like !! –-version)

Lat’s say that your last typed command is whoami, in this case, typing the above command it’s like you would have typed

whoami --version

Event designator may also be followed by modifiers. The modifiers follow the word designator, if there is one.

Modifier

Purpose

h

r

e

t

p

q

x

s/old/new

Remove a trailing pathname component, leaving the head

Removes a trailing suffix of the form .xxx

Removes all but the trailing suffix

Removes all leading pathname components, leaving the tail

Prints the resulting command but doesn’t execute it

Quote the substituted word, escaping further substitutions

Quote the substituted words, breaking them into words at blanks and newlines

Substitutes new for old

Tabella 3 – modifiers

For example if you have just type the following command

grep -Hnr “Fabio Bombardi” .

And you want to retype the above command but to search for “Elena Bombardi” you could type:

!!:s/Fabio/Elena

And you get the following command:

grep -Hnr “Elena Bombardi” .

Setting the X server keyboard map type

If you want to set a different map, let’s say Italian, to your X sever, you could type the following command:

setxkbmap -layout it

Patterns and Pattern Matching

Patterns are strings that can contain wildcard characters.

Operator

Meaning

${variable#pattern}

${variable##pattern}

${variable%pattern}

${variable%%pattern}

${variable/pattern/string}

${variable//pattern/string}

If the pattern matches the beginning of the variable’s value, delete the shortest part that matches and return the rest.

If the pattern matches the beginning of the variable’s value, delete the longest part that matches and return the rest.

If the pattern matches the end of the variable’s value, delete the shortest part that matches and return the rest.

If the pattern matches the end of the variable’s value, delete the longest part that matches and return the rest.

The longest match to pattern in variable is replaced by string. In the first from, only the first match is replaced. In the second form, all the matches are replaced. If the pattern begins with a #, it must match at the start of the variable. If it begins with a %, it must match with the end of the variable. If string is null, the matches are deleted. If variable is @ or *, the operation is applied to each positional parameter in turn and the expansion is the result list.

Tabella 4 – Pattern-Matching Operators

If you want some exaples here you are:

$path /home/shadowsheep/testpatterns/hello.shadowsheep.test

$path##/*/ hello.shadowsheep.test

$path#/*/ shadowsheep/testpatterns/hello.shadowsheep.test

$path%.* /home/shadowsheep/testpatterns/hello.shadowsheep

$path%%.* /home/shadowsheep/testpatterns/hello

If you want to substitute all the occurrence in a string you may want to type:

echo ${PATH//:/’\n’}

/home/usr/bin\n/usr/local/bin\n/bin\n

If you want the echo command to interpret the backslashes character ( like \n) so you may want to type:

echo –e ${PATH//:/’\n’}

/home/usr/bin

/usr/local/bin

/bin

Lessons

Lesson 1

If you want to edit a text file without open a text editor you can use the echo command in the following way: 

fbombardi@linux:~/workspace/shell_commands> echo -e "a\n\

a\n\

a\n\

mount -n -t nfs -o nolock,rsize=1024,wsize=1024 172.27.30.179:/home/nfs /NetShared\n\

b\n\

b\n\

end" > test.log

In this way you create a text file named test.log whose content is the following:

a

a

a

mount -n -t nfs -o nolock,rsize=1024,wsize=1024 172.27.30.179:/home/nfs /NetShared

b

b

end

Now if you want to type the command

mount -n -t nfs -o nolock,rsize=1024,wsize=1024 172.27.30.179:/mnt/nfs /NetShared

You can use the following shortcut:

fbombardi@linux:~/workspace/shell_commands> more test.log | grep "mount -n" | sed -e s/home/mnt/

Or even better you can use this shortcut:

fbombardi@linux:~/workspace/shell_commands> grep "mount -n" test.log | sed -e s/home/mnt/

I think that this should be useful when you have a command in a very full written file, otherwise I think that you could be faster in typing the command from scratch =).

Lesson 2

Here we are again. This time we’ll go deeper in the world of the I/O redirection. Let’s say we want to get rid of all the boring messages that the command make show us during the compiling and linking time. What we have to do? The answer is simple and is located in the line below:

make > /dev/null 2>&1

In this way all the boring messages will be redirected in the “black-hole” /dev/null.

Let’s see now that we want to decide which kind of messages to display. I’ll give you a gift showing you on of my favorite shell script:

#

# My Make

# Use this program to customize the make output messages

#

# @author Fabio Bombardi

# @location Datasensor

# @version 2.1.0

# @last-updated 2k6.09.24

#

if [ -n $2 ] && [ "$2" = "-silent" ]; then

break;

else

echo -e "\n"

echo -e \#

echo -e \# My Make

echo -e \# Use this program to customize the make output messages

echo -e \#

echo -e \# @author "\t\t" Fabio Bombardi

echo -e \# "\t\t\t\t" fbombardi@datasensor.com

echo -e \# @location "\t\t" Datasensor

echo -e \# @version "\t\t" 2.1.0

echo -e \# @last-updated "\t" 2k6.09.24

echo -e \#

echo -e "\n"

fi

if [ -z $1 ]; then

echo -e "usage: mymake <type-of-massage>\n\n\t<type-of-massage>=\n\t\twarning\n\t\terror\n\t\tall\n\t\tclean\n"

exit -1

fi

case $1 in

warning )

make 2>&1 | grep "warning" | cat ;;

error )

make 2>&1 | grep "Error" | cat ;;

all )

make 2>&1 | grep "*" | cat ;;

clean)

make clean ;;

* )

echo -e "\ndefault selection: warning\n"

$0 wanrning

esac

In the above shell script the line in bold shows us only the messages containing the word “warning” and hiding all the other messages.

Lesson 3

Let’s say now that we want not only to choose between the make output messages but also to give different colors to this messages (e.g. yellow for warnings and red for error).

In this case we may want to make the following changes in the case statement:

case $1 in

warning )

GREP_COLOR="1;33"

make 2>&1 | grep --color=always "warning" | cat ;;

error )

GREP_COLOR="0;31"

make 2>&1 | grep --color=always "Error" | cat ;;

all )

make 2>&1 | grep "*" | cat ;;

clean)

make clean ;;

* )

echo -e "\ndefault selection: warning\n"

$0 warning ;;

esac

The grep command has the option flag –color that along with the variable GREP_COLOR highlights the pattern word with the color set in the variable GREP_COLOR.

With the above changes we should get something like that:

img_processing.cpp:148: warning: right-hand operand of comma has no effect

img_processing.cpp:367: warning: converting to `unsigned char’ from `float’

img_processing.cpp:477: warning: converting to `int’ from `float’

img_processing.cpp:478: warning: converting to `int’ from `float’

Colors

We could choose, of course, among a plethora of color:

Dark gray: 1;30

Blue: 0;34

Light Blue: 1;34

Green: 0;32

Light green: 1;32

Cyan: 0;36

Light cyan: 1;36

Red: 0;31

Light red: 1;31

Purple: 0;35

Light purple: 1;35

Brown: 0;33

Yellow: 1;33

Light gray: 0;37

White: 1;37

Lesson 4

Let’s say now that we want not only to highlight the keywords (warning, error) but the entire lines!

What follows is what we could do to be successful:

case $1 in

warning )

echo -e "\033[1;33m"

make 2>&1 | grep "warning" | cat

echo -e "\033[1;37m" ;;

error )

echo -e "\033[1;31m"

make 2>&1 | grep --color=always "Error" | cat

echo -e "\033[1;37m" ;;

all )

make 2>&1 | grep "*" | cat ;;

clean)

echo -e "\033[1;32m"

make clean

echo -e "\033[1;37m\n" ;;

* )

echo -e "\033[1;35m"

echo -e "\ndefault selection: warning\n"

echo -e "\033[1;37m\n"

$0 warning ;;

esac

And we’ll get the following output:

img_processing.cpp:148: warning: right-hand operand of comma has no effect

img_processing.cpp:367: warning: converting to `unsigned char’ from `float’

img_processing.cpp:477: warning: converting to `int’ from `float’

img_processing.cpp:478: warning: converting to `int’ from `float’

A little of Bash Shell

Script bash per controllo esecuzione di un processo

Fabio Bombardi

Per controllare se un processo è in esecuzione su linux ed eventualmente farlo ripartire se non lo è, si può utilizzare questo semplice script:

#!/bin/bash
#check_process_and_restart_it.sh
#make sure your-process is running

export DISPLAY=:0 #needed if you are running a simple gui app.

process=your-process
makerun="/usr/bin/python /usr/bin/your-process"

if ps ax | grep -v grep | grep $process > /dev/null
        then
                exit
        else
        $makerun &

	echo "Date: " $(date) >> /root/scripts/your-process.log
fi
exit
Script bash per controllo esecuzione di un processo