Managed Kubernetes now available in Open Beta. Test out the new service yourself at your Control Panel.
Managed Kubernetes now available in Open Beta. Test out the new service yourself at your Control Panel.
Snort is a popular choice for running a network intrusion detection systems or NIDS for short. It monitors the package data sent and received through a specific network interface. NIDS can catch threats targeting your system vulnerabilities using signature-based detection and protocol analysis technologies. NIDS software, when installed and configured appropriately, can identify the latest attacks, malware infections, compromised systems, and network policy violations. In this guide, you will find instructions on how to install Snort on Debian 9. The install guide is also available for cloud servers running CentOS 7 and Ubuntu 16.
Snort is one of the most commonly used network-based IDS. It is a lightweight, open source, available on a multitude of platforms, and can be comfortably installed even on the smallest of cloud server instances. Although Snort is capable of much more than just network monitoring, this guide shows how to configure and run Snort in NIDS mode with a basic setup that you can later expand as needed.
Setting up a basic configuration of Snort on Debian is fairly simple but takes a few steps to complete. You will first need to install all the prerequisite software to ready your cloud server for installing Snort itself. Install the required libraries with the following command.
sudo apt install -y gcc libpcre3-dev zlib1g-dev libluajit-5.1-dev libpcap-dev openssl libssl-dev libnghttp2-dev libdumbnet-dev bison flex libdnet autoconf libtool
With the prerequisites fulfilled, next up is how to install Snort on Debian 9. Snort can be downloaded and installed manually from the source. Below you will find instructions on how to get this done.
Setting up Snort on Debian from the source code consists of a couple of steps: downloading the code, configuring it, compiling the code, installing it to an appropriate directory, and lastly configuring the detection rules.
Start by making a temporary download folder to your home directory and then changing into it with the command below.
mkdir ~/snort_src && cd ~/snort_src
Snort itself uses something called Data Acquisition library (DAQ) to make abstract calls to packet capture libraries. Download the latest DAQ source package from the Snort website with the wget command underneath. Replace the version number in the command if a newer source available.
wget https://www.snort.org/downloads/snort/daq-2.0.7.tar.gz
The download will only take a few seconds. When complete, extract the source code and jump into the new directory with the following commands.
tar -xvzf daq-2.0.7.tar.gz cd daq-2.0.7
The latest version requires an additional step to auto reconfigure DAQ before running the config. Use the command below which requires you need to have autoconf and libtool installed.
autoreconf -f -i
Afterwards, run the configuration script using its default values, then compile the program with make and finally install DAQ.
./configure && make && sudo make install
With the DAQ installed you can get started with Snort, change back to the download folder.
cd ~/snort_src
Next, download the Snort source code with wget. You can find the latest version number on the Snort downloads page. Replace it in the following command if necessary.
wget https://www.snort.org/downloads/snort/snort-2.9.16.tar.gz
Once the download is complete, extract the source and change into the new directory with these commands.
tar -xvzf snort-2.9.16.tar.gz cd snort-2.9.16
Then configure the installation with sourcefire enabled, run make and make install.
./configure --enable-sourcefire && make && sudo make install
With that done, continue below on how to set up the configuration files.
Next, you will need to configure Snort for your system. This includes editing some configuration files, downloading the rules that Snort will follow, and taking Snort for a test run.
Start with updating the shared libraries using the command underneath.
sudo ldconfig
Snort on Debian gets installed to /usr/local/bin/snort directory, it is good practice to create a symbolic link to /usr/sbin/snort.
sudo ln -s /usr/local/bin/snort /usr/sbin/snort
To run Snort on Debian safely without root access, you should create a new unprivileged user and a new user group for the daemon to run under.
sudo groupadd snort sudo useradd snort -r -s /sbin/nologin -c SNORT_IDS -g snort
Then create the folder structure to house the Snort configuration, just copy over the commands below.
sudo mkdir -p /etc/snort/rules sudo mkdir /var/log/snort sudo mkdir /usr/local/lib/snort_dynamicrules
Set the permissions for the new directories accordingly.
sudo chmod -R 5775 /etc/snort sudo chmod -R 5775 /var/log/snort sudo chmod -R 5775 /usr/local/lib/snort_dynamicrules sudo chown -R snort:snort /etc/snort sudo chown -R snort:snort /var/log/snort sudo chown -R snort:snort /usr/local/lib/snort_dynamicrules
Create new files for the white and blacklists as well as the local rules.
sudo touch /etc/snort/rules/white_list.rules sudo touch /etc/snort/rules/black_list.rules sudo touch /etc/snort/rules/local.rules
Then copy the configuration files from the download folder.
sudo cp ~/snort_src/snort-2.9.16/etc/*.conf* /etc/snort sudo cp ~/snort_src/snort-2.9.16/etc/*.map /etc/snort
Next up, you will need to download the detection rules Snort will follow to identify potential threats. Snort provides three tiers of rule sets, community, registered and subscriber rules.
Underneath you can find instructions for downloading both community rules or registered user rule sets.
If you just want to quickly test out Snort, grab the community rules using wget with the command below.
wget https://www.snort.org/rules/community -O ~/community.tar.gz
Extract the rules and copy them to your configuration folder.
sudo tar -xvf ~/community.tar.gz -C ~/
sudo cp ~/community-rules/* /etc/snort/rules
By default, Snort on Debian expects to find a number of different rule files which are not included in the community rules. You can easily comment out the unnecessary lines using the sed command underneath.
sudo sed -i 's/include $RULE_PATH/#include $RULE_PATH/' /etc/snort/snort.conf
You can also take a moment and register on the Snort website. Registering gives you access to use their Oink code to download the registered user rules. You can find the code in the Snort user account details.
Replace the oinkcode in the following command with your personal code.
wget https://www.snort.org/rules/snortrules-snapshot-29160.tar.gz?oinkcode=oinkcode -O ~/registered.tar.gz
Once downloaded, extract the rules over to your configuration directory.
sudo tar -xvf ~/registered.tar.gz -C /etc/snort
The rule sets for the registered users include an extensive amount of useful preconfigured detection rules. If you tried out Snort with the community rules first, you can enable additional rules by uncommenting their inclusions towards the end of the snort.conf file.
With the configuration and rule files in place, edit the snort.conf to modify a few parameters. Open the configuration file in your favourite text editor, for example using nano with the command below.
sudo nano /etc/snort/snort.conf
Find these sections shown below in the configuration file and change the parameters to reflect the examples here.
# Setup the network addresses you are protecting
ipvar HOME_NET server_public_IP/32
# Set up the external network addresses. Leave as "any" in most situations ipvar EXTERNAL_NET !$HOME_NET
# Path to your rules files (this can be a relative path) var RULE_PATH /etc/snort/rules var SO_RULE_PATH /etc/snort/so_rules var PREPROC_RULE_PATH /etc/snort/preproc_rules
# Set the absolute path appropriately var WHITE_LIST_PATH /etc/snort/rules var BLACK_LIST_PATH /etc/snort/rules
In the same snort.conf file, scroll down to the section 6 and set the output for unified2 to log under filename of snort.log like below.
# unified2 # Recommended for most installs output unified2: filename snort.log, limit 128
Lastly, scroll down towards the bottom of the file to find the list of included rule sets. You will need to uncomment the local.rules to allow Snort to load any custom rules.
include $RULE_PATH/local.rules
If you are using the community rules, add the line underneath to your ruleset as well, for example just below your local.rules line.
include $RULE_PATH/community.rules
Once you are done with the configuration file, save the changes and exit the editor.
Your Snort should now be ready to run. Test the configuration using the parameter -T to enable test mode.
sudo snort -T -c /etc/snort/snort.conf
After running the Snort configuration test, you should get a message like this example below.
--== Initialization Complete ==-- ,,_ -*> Snort! <*- o" )~ Version 2.9.16 GRE (Build 118) '''' By Martin Roesch & The Snort Team: http://www.snort.org/contact#team Copyright (C) 2014-2020 Cisco and/or its affiliates. All rights reserved. Copyright (C) 1998-2013 Sourcefire, Inc., et al. Using libpcap version 1.8.1 Using PCRE version: 8.39 2016-06-14 Using ZLIB version: 1.2.11 Rules Engine: SF_SNORT_DETECTION_ENGINE Version 3.1 Preprocessor Object: SF_DCERPC2 Version 1.0 Preprocessor Object: SF_SSH Version 1.1 Preprocessor Object: SF_FTPTELNET Version 1.2 Preprocessor Object: SF_SDF Version 1.1 Preprocessor Object: SF_DNP3 Version 1.1 Preprocessor Object: SF_REPUTATION Version 1.1 Preprocessor Object: SF_IMAP Version 1.0 Preprocessor Object: SF_SMTP Version 1.1 Preprocessor Object: SF_GTP Version 1.1 Preprocessor Object: appid Version 1.1 Preprocessor Object: SF_MODBUS Version 1.1 Preprocessor Object: SF_POP Version 1.0 Preprocessor Object: SF_DNS Version 1.1 Preprocessor Object: SF_SSLPP Version 1.1 Preprocessor Object: SF_SIP Version 1.1 Snort successfully validated the configuration! Snort exiting
In case you get an error, the print out should tell you what the problem was and where to fix it. Most likely problems are missing files or folders, which you can usually resolve by either adding any you might have missed in the setup above, or by commenting out unnecessary inclusion lines in the snort.conf file. Check the configuration part and try again.
To test if Snort is logging alerts as intended, add a custom detection rule alert on incoming ICMP connections to the local.rules file. Open your local rules in a text editor.
sudo nano /etc/snort/rules/local.rules
Then add the following line to the file.
alert icmp any any -> $HOME_NET any (msg:"ICMP test"; sid:10000001; rev:001;)
The rule consists of the following parts:
Save the local.rules and exit the editor.
Start Snort with -A console options to print the alerts to stdout. You will need to select the correct network interface with the public IP address of your server, for example, eth0.
sudo snort -A console -i eth0 -u snort -g snort -c /etc/snort/snort.conf
If you are not sure which interface to use, check your UpCloud control panel for the public IPv4 address of your server in the Network settings. You can also use the following command on your server.
ip addr
The output will list all of your currently configured network interfaces. Find the one with the same public IP address as shown in the Network settings, commonly eth0.
With Snort up and running, ping your cloud server from any other computer. You should see a notice for each ICMP call in the terminal running Snort.
07/12-11:20:33.501624 [**] [1:10000001:1] ICMP test [**] [Priority: 0] {ICMP} 83.136.252.118 -> 80.69.173.202
After the alerts show up you can stop Snort with ctrl+C.
Snort records the alerts to a log under /var/log/snort/snort.log.timestamp, where the timestamp is the point in time when Snort was started marked in Unix time. You can read the logs with the command underneath. Since you have only run Snort once, there is only one log, complete your command by pressing TAB.
snort -r /var/log/snort/snort.log.
The log shows a warning for each ICMP call with source and destination IPs, time and date, plus some additional info as shown in the example below.
WARNING: No preprocessors configured for policy 0. 07/12-11:20:33.501624 83.136.252.118 -> 80.69.173.202 ICMP TTL:63 TOS:0x0 ID:20187 IpLen:20 DgmLen:84 DF Type:8 Code:0 ID:13891 Seq:1 ECHO
To run Snort on Debian as a service in the background you will need to add a startup script for Snort. Open a new a file in a text editor for example with the next command.
sudo nano /lib/systemd/system/snort.service
Enter the following to the file, save and exit the editor.
[Unit] Description=Snort NIDS Daemon After=syslog.target network.target [Service] Type=simple ExecStart=/usr/local/bin/snort -q -u snort -g snort -c /etc/snort/snort.conf -i eth0 [Install] WantedBy=multi-user.target
With the service defined, reload the systemctl daemon.
sudo systemctl daemon-reload
Snort can then be run with the configuration you set up using the command below.
sudo systemctl start snort
The startup script also includes other usual systemctl commands: stop, restart, and status. For example, you can check the status of the service with the following command.
sudo systemctl status snort
Congratulations, you should have now successfully configured and tested a network-based intrusion detection system. This guide however only covers the very basics with an introduction to Snort and NIDS in general. To get more out of your installation, check out the deployment guides over at the Snort documents page, or jump right into writing your own detection rules with their helpful Snort rules info graph.
Fabricio
apt install -y libluajit-5.1-dev
Fabricio
By the way, good job :)
Oscar Sommerbo
Why not use the debian packages available?
telfort Pierre
i ran into an error when i tried to test the snort rules, there it is ‘ERROR: /etc/snort/snort.conf(104) Missing argument to RULE_PATH’ How do i fix it?
Adan
i can’t run snort after installing it. I’m using Debian 9
sachin
i want to know whether it is possible to take alert mode example console fast or full from snort.conf
herl
Installing snort on raspbian fails because of luajit :
$ ./configure –enable-sourcefire && make && sudo make install
Is stopped because of that error :
checking for luajit…
ERROR! LuaJIT library not found. Go get it from http://www.luajit.org/ (or)
Try compiling without openAppId using ‘–disable-open-appid’
configure: error: “Fatal!”
I did install luajit:
apt install luajit
apt install libluajit-5.1-dev
Running armbian on orangepi
Linux orangepi 4.19.62-sunxi #5.92 SMP Wed Jul 31 22:07:23 CEST 2019 armv7l GNU/Linux
Lorenzo
Hello, thank you very much for this guide!
I need a few, more, information:
– snort check every data coming from every port?
If yes, how can I examine data checked?
If no, how can I select one port to be controlled?
– snort is running in background, I have to start it when I switch on the VM or not?
Lorenzo
Thank you very much for the advice!
By the way, if I had set a blacklist, every packet sent from that IP is forbidden, right?
Anastasia
Hi, thank you so much for the guide.
I try to install snort on MacOS, but once I do ./configure to configure the environment before intall snort, I got a message like this:
ERROR! openssl/x509.h or openssl library not found.
Try compiling without openAppId using ‘–disable-open-appid’
configure: error: “Fatal!”
I have already double-checked that the openssl has been installed, so could you please help me what is happened here, or give me some suggestions, please.
Thank you so much
Salvador
I have a big problem, when I try to run sudo snort -A console -i eth0 -u snort -g snort -c /etc/snort/snort.conf it stays stucked in “commencing packet processing pid=1534”
I am in debian 10 buster, what should I do with this?
I am in a virtual machine in a Mac OS device. When I do the test above, it runs perfectly. I started my interface enp0s3 but nothing happens. Please help
Gerald
I have got an error while running “./configure && make && sudo make install” Now snort daq goes to version 2.0.7. Could you please help. Thanks.
error is…
Build AFPacket DAQ module.. : yes
Build Dump DAQ module…… : yes
Build IPFW DAQ module…… : yes
Build IPQ DAQ module……. : no
Build NFQ DAQ module……. : no
Build PCAP DAQ module…… : yes
Build netmap DAQ module…. : no
CDPATH=”${ZSH_VERSION+.}:” && cd . && /bin/bash /home/pi/snort_src/daq-2.0.7/missing aclocal-1.15 -I m4
/home/pi/snort_src/daq-2.0.7/missing: line 81: aclocal-1.15: command not found
WARNING: ‘aclocal-1.15’ is missing on your system.
You should only need it if you modified ‘acinclude.m4’ or
‘configure.ac’ or m4 files included by ‘configure.ac’.
The ‘aclocal’ program is part of the GNU Automake package:
It also requires GNU Autoconf, GNU m4 and Perl in order to run:
make: *** [Makefile:372: aclocal.m4] Error 127
Ben
Hello janne,
im using this snort guide of installation. And after configuring the paths, on snort.conf.
Im trying to validate setting, using this command “sudo snort -T -c /etc/snort/snort.conf” on /snort_src/etc/ path. It popped out the next message, sudo snort command not found. On step 2, installing from the source i made it same way. What should be the error ¿
postdata, sorry for my english.
Viktor
HI. I followed your excellent tutorial and all worked!
I still have one question:
When I use the command : “sudo snort -A console -i eth0 -u snort -g snort -c /etc/snort/snort.conf”, I only see pings which have as destination the machine where snort is configured.
How can I do to see all icmp traffic in my network?
Thx
Riska
Hi , i have problem :
ERROR! daq_status library not found, go get it from
http://www.snort.org/.
What should i do?
Hoi
Hi sir, i have a problem here. Did this guide three times.
The error message is “ERROR: /etc/snort//etc/snort/rules/app-detect.rules(0) Unable to open rules file “/etc/snort//etc/snort/rules/app-detect.rules”: No such file or directory.”
Please help me solve it as I would like to use this for my project on information security. Thank you.
Hoi
there was no file called app-detect.rules.* sorry
Mohit
has anyone had success installing barnyard on debian bullseye?
I am getting an error while doing a make on barnyard from source.
Help appreciated.
output as follows:
[email protected]:/usr/src/barnyard2# make
make all-recursive
make[1]: Entering directory ‘/usr/src/barnyard2’
Making all in src
make[2]: Entering directory ‘/usr/src/barnyard2/src’
Making all in sfutil
make[3]: Entering directory ‘/usr/src/barnyard2/src/sfutil’
make[3]: Nothing to be done for ‘all’.
make[3]: Leaving directory ‘/usr/src/barnyard2/src/sfutil’
Making all in output-plugins
make[3]: Entering directory ‘/usr/src/barnyard2/src/output-plugins’
gcc -DHAVE_CONFIG_H -I. -I../.. -I.. -I ../sfutil -I/usr/include/mysql -DENABLE_MYSQL -g -O2 -Wall -c -o spo_alert_fwsam.o spo_alert_fwsam.c
In file included from /usr/include/pcap/pcap.h:87,
from /usr/include/pcap.h:43,
from ../barnyard2.h:46,
from spo_alert_fwsam.c:91:
spo_alert_fwsam.c:118:13: error: two or more data types in declaration specifiers
118 | typedef int SOCKET;
| ^~~~~~
spo_alert_fwsam.c:118:1: warning: useless type name in empty declaration
118 | typedef int SOCKET;
| ^~~~~~~
spo_alert_fwsam.c: In function ‘FWsamReadLine’:
spo_alert_fwsam.c:620:9: warning: this ‘if’ clause does not guard… [-Wmisleading-indentation]
620 | if(p>buf);
| ^~
spo_alert_fwsam.c:621:13: note: …this statement, but the latter is misleadingly indented as if it were guarded by the ‘if’
621 | strcpy(buf,p);
| ^~~~~~
spo_alert_fwsam.c: In function ‘AlertFWsam’:
spo_alert_fwsam.c:981:18: warning: variable ‘cn’ set but not used [-Wunused-but-set-variable]
981 | ClassType *cn = NULL;
| ^~
spo_alert_fwsam.c:980:18: warning: variable ‘sn’ set but not used [-Wunused-but-set-variable]
980 | SigNode *sn = NULL;
| ^~
spo_alert_fwsam.c:973:27: warning: variable ‘lastbsp’ set but not used [-Wunused-but-set-variable]
973 | static unsigned short lastbsp[FWSAM_REPET_BLOCKS];
| ^~~~~~~
make[3]: *** [Makefile:391: spo_alert_fwsam.o] Error 1
make[3]: Leaving directory ‘/usr/src/barnyard2/src/output-plugins’
make[2]: *** [Makefile:498: all-recursive] Error 1
make[2]: Leaving directory ‘/usr/src/barnyard2/src’
make[1]: *** [Makefile:412: all-recursive] Error 1
make[1]: Leaving directory ‘/usr/src/barnyard2’
make: *** [Makefile:344: all] Error 2
justin malley
The BEST set of instructions for installng Snort in Kali Linux available . thankyou and much appreciated.
Ace
Perfect.
Thank you very much for this tutorial.
I have applied it on Raspbian and it works!
Kudos!
Jorge Tejada
I am getting this error:
[email protected]:~$ sudo apt install -y gcc libpcre3-dev zlib1g-dev libluajit-5.1-dev libpcap-dev openssl libssl-dev libnghttp2-dev libdumbnet-dev bison flex libdnet autoconf libtool
Reading package lists… Done
Building dependency tree
Reading state information… Done
E: Unable to locate package libnghttp2-dev
Gianluca
Hi
I am getting this error:
sp_rpc_check.c:32:10: fatal error: rpc/rpc.h: No such file or directory
32 | #include
| ^~~~~~~~~~~
compilation terminated.
make[4]: *** [Makefile:489: sp_rpc_check.o] Error 1
make[4]: Leaving directory ‘/root/snort_src/snort-2.9.17/src/detection-plugins’
make[3]: *** [Makefile:440: all] Error 2
make[3]: Leaving directory ‘/root/snort_src/snort-2.9.17/src/detection-plugins’
make[2]: *** [Makefile:558: all-recursive] Error 1
make[2]: Leaving directory ‘/root/snort_src/snort-2.9.17/src’
make[1]: *** [Makefile:516: all-recursive] Error 1
make[1]: Leaving directory ‘/root/snort_src/snort-2.9.17’
make: *** [Makefile:382: all] Error 2
i’m using ubuntu 20.10
Thanks
franck
┌──(kali㉿kali)-[~]
└─$ snort -r /var/log/snort/snort.log
Running in packet dump mode
–== Initializing Snort ==–
Initializing Output Plugins!
pcap DAQ configured to read-file.
ERROR: Can’t initialize DAQ pcap (-1) – unknown file format
Fatal Error, Quitting..
amelia
when i type this command:./configure && make && sudo make install
i get an error
:error in /root/snort_src/daq-2.0.7
something went wrong bootstrapping makefile fragments for automatic dependency tracking debian.try re-running configure with the disable dependancy tracking
Momo Francois
Good evening can you help me with this error below
wget https://www.snort.org/rules/snortrules-snapshot-29160.tar.gz?oinkcode=oinkcode -O ~/registered.tar.gz
–2021-08-25 08:27:58– https://www.snort.org/rules/snortrules-snapshot-29160.tar.gz?oinkcode=oinkcode
Resolving http://www.snort.org (www.snort.org)… 104.18.138.9, 104.18.139.9, 2606:4700::6812:8b09, …
Connecting to http://www.snort.org (www.snort.org)|104.18.138.9|:443… connected.
HTTP request sent, awaiting response… 422 Unprocessable Entity
2021-08-25 08:27:59 ERROR 422: Unprocessable Entity.
suresh
Thanks for the detailed explanation sir. I have successfully installed Snort2x and working fine in Raspberry pi. But now when I am trying to install Snort3, I am getting error. I followed the instructions provided in the user manual for Snort3 Ubuntu installation as no manual for Debian. In the dependency tools, Hyperscan tool I could not install as error generated during compile. Then I skipped Hyperscan and proceeded for Snort3 Installation. Still I am getting an error and couldn’t succeed. Please help me out. Thank you.
Error:
collect2: error: ld returned 1 exit status
make[2]: *** [src/CMakeFiles/snort.dir/build.make:1679: src/snort] Error 1
make[1]: *** [CMakeFiles/Makefile2:2978: src/CMakeFiles/snort.dir/all] Error 2
make: *** [Makefile:152: all] Error 2
nel23FX
really good job (y)
big thanks for this
Ugo
Hello
I am getting this error while trying to install snort on Kali
sp_rpc_check.c:32:10: fatal error: rpc/rpc.h: No such file or directory
32 | #include
| ^~~~~~~~~~~
compilation terminated.
make[4]: *** [Makefile:489: sp_rpc_check.o] Error 1
make[4]: Leaving directory ‘/home/kali/snort_src/snort-2.9.19/src/detection-plugins’
make[3]: *** [Makefile:440: all] Error 2
make[3]: Leaving directory ‘/home/kali/snort_src/snort-2.9.19/src/detection-plugins’
make[2]: *** [Makefile:558: all-recursive] Error 1
make[2]: Leaving directory ‘/home/kali/snort_src/snort-2.9.19/src’
make[1]: *** [Makefile:516: all-recursive] Error 1
make[1]: Leaving directory ‘/home/kali/snort_src/snort-2.9.19’
make: *** [Makefile:382: all] Error 2
Suresh
Dear sir, If I want to use snort alert_unixsock option for output plugin, it was given in one of the snort reference document (README.UNSOCK), Snort has to be built with spo_unsock.c/h output plugin. Can you please guide me how to do it. Thanks