In this guide, we will cover the installation and configuration of LibreNMS on CentOS 7 server with Nginx and optional Letsencrypt SSL certificate for security.
What is LibreNMS?
LibreNMS is a community-based GPL-licensed auto-discovering network monitoring tool based on PHP, MySQL, and SNMP. LibreNMS includes support for a wide range of network hardware and operating systems including Juniper, Cisco, Linux, Foundry, FreeBSD, Brocade, HP, Windows and many more. It is a fork of “Observium” monitoring tool.
Features of LibreNMS
Below are the top features of LibreNMS networking monitoring tool
- Has Automatic discovery – It will automatically discover your entire network using CDP, FDP, LLDP, OSPF, BGP, SNMP, and ARP
- API Access – LibreNMS provides a full API to manage, graph and retrieve data from your install.
- Automatic Updates – With LibreNMS you get to stay up to date automatically with new features and bug fixes.
- Customisable alerting – Highly flexible alerting system, notify via email, IRC, slack and more.
- Support for Distributed Polling through horizontal scaling which grows with your network
- Billing system – Easily generate bandwidth bills for ports on your network based on usage or transfer.
- Android and iOS application – There is a native iPhone/Android App is available which provides core functionality.
- Multiple authentication methods: MySQL, HTTP, LDAP, Radius, Active Directory
- Integration support for NfSen, collectd, SmokePing, RANCID, Oxidized
Install LibreNMS on CentOS 7 with Let’s Encrypt and Nginx
Follow steps provided here to have a running an operation LibreNMS monitoring tool on your CentOS 7 server. Ensure your system is updated and rebooted:
sudo yum -y update
sudo rebootAfter reboot set timezone and chronyd:
sudo yum -y install chrony
sudo timedatectl set-timezone Africa/Nairobi
sudo timedatectl set-ntp yes
sudo chronyc sourcesPut SELinux into permissive mode
Run the commands below to put SELinux in Permissive mode:
sudo setenforce 0
To persist the change, edit SELinux configuration file
sudo sed -i 's/^SELINUX=.*/SELINUX=permissive/g' /etc/selinux/config
cat /etc/selinux/config | grep SELINUX=Add EPEL repository to the system
Enable EPEL repository on your system
sudo yum -y install vim epel-release yum-utilsInstall required dependencies
Install all dependencies required to install and run LibreNMS on CentOS 7:
sudo yum -y install zip unzip git cronie wget fping net-snmp net-snmp-utils ImageMagick jwhois mtr rrdtool MySQL-python nmap python-memcached python3 python3-pip python3-develInstall PHP and Nginx
PHP will be installed from REMI repository, add it to the system like below:
sudo yum -y install http://rpms.remirepo.net/enterprise/remi-release-7.rpmDisable remi-php54 repo which is enabled by default, and enable repository for PHP 7.2
sudo yum-config-manager --disable remi-php54
sudo yum-config-manager --enable remi-php74Then finally install required php modules
sudo yum -y install php php-{cli,mbstring,process,fpm,mysqlnd,zip,snmp,devel,gd,mcrypt,mbstring,curl,xml,pear,bcmath}Configure PHP
Edit PHP-FPM configuration file:
sudo vim /etc/php-fpm.d/www.conf
Set below variables
user = nginx
group = nginx
listen = /var/run/php-fpm/php-fpm.sock
listen.owner = nginx
listen.group = nginx
listen.mode = 0660Set PHP timezone
$ sudo vim /etc/php.ini
date.timezone = Africa/NairobiInstall nginx web server
Install Nginx web server on CentOS 7:
sudo yum -y install nginx
Start nginx and php-fpm service
for i in nginx php-fpm; do
sudo systemctl enable $i
sudo systemctl restart $i
doneInstall and Configure Database Server
Install MariaDB database on your CentOS 7 server.
curl -LsS -O https://downloads.mariadb.com/MariaDB/mariadb_repo_setup
sudo bash mariadb_repo_setup
sudo yum install MariaDB-server MariaDB-client MariaDB-backup
sudo systemctl enable --now mariadb
sudo mariadb-secure-installationEdit my.cnf file and add below lines within the [mysqld] section:
$ sudo vim /etc/my.cnf.d/server.cnf
[mysqld]
innodb_file_per_table=1
lower_case_table_names=0Restart the MariaDB server after making the changes
sudo systemctl restart mariadbOnce the database server has been installed and running, login as root user:
$ sudo mysql -u root -pCreate a database and user:
CREATE DATABASE librenms CHARACTER SET utf8 COLLATE utf8_general_ci;
GRANT ALL PRIVILEGES ON librenms.* TO 'librenms_user'@'localhost' IDENTIFIED BY "Password1234!";
FLUSH PRIVILEGES;
EXIT;Install and Configure LibreNMS on CentOS 7
If you want to use Letsencrypt SSL certificate, you need to first request for it. Run below commands as root user
sudo yum -y install certbot python2-certbot-nginxEnable http port on the firewall if you have firewalld service running
sudo firewall-cmd --add-service={http,https} --permanent
sudo firewall-cmd --reloadNow obtain the certificate to use
export DOMAIN='librenms.example.com'
export EMAIL="[email protected]"
sudo certbot certonly --standalone -d $DOMAIN --preferred-challenges http --agree-tos -n -m $EMAIL --keep-until-expiringThe certificate will be placed under /etc/letsencrypt/live/librenms.example.com/ directory
Clone LibreNMS project from Github
Add librenms user:
sudo useradd librenms -d /opt/librenms -M -r
sudo usermod -aG librenms nginxClone LibreNMS project from Github:
cd /opt
sudo git clone https://github.com/librenms/librenms.git
sudo chown librenms:librenms -R /opt/librenmsInstall PHP dependencies
cd /opt/librenms
sudo ./scripts/composer_wrapper.php install --no-devA successful install should have output similar to below:
....
Requirement already satisfied: typing-extensions>=3.6.4; python_version < "3.8" in /root/.local/lib/python3.6/site-packages (from importlib-metadata>=1.0; python_version < "3.8"->redis>=3.0->-r requirements.txt (line 3))
Installing collected packages: psutil, command-runner
Running setup.py install for psutil: started
Running setup.py install for psutil: finished with status 'done'
Successfully installed command-runner-1.3.0 psutil-5.9.0Copy and configure SNMP configuration template:
Run the commands below in the terminal:
sudo cp /opt/librenms/snmpd.conf.example /etc/snmp/snmpd.conf
sudo vim /etc/snmp/snmpd.confSet your community string by replacing RANDOMSTRINGGOESHERE
com2sec readonly default MyInternalNetworkDownload distribution version identifier script
sudo curl -o /usr/bin/distro https://raw.githubusercontent.com/librenms/librenms-agent/master/snmp/distro
sudo chmod +x /usr/bin/distroThen start and enable snmpd service
sudo systemctl enable snmpd
sudo systemctl restart snmpdWhen all is done, create nginx configuration file for LibreNMS
Nginx configuration without SSL
This is placed under /etc/nginx/conf.d/librenms.conf
server {
listen 80;
server_name librenms.example.com;
root /opt/librenms/html;
index index.php;
charset utf-8;
gzip on;
gzip_types text/css application/javascript text/javascript application/x-javascript image/svg+xml text/plain text/xsd text/xsl text/xml image/x-icon;
location / {
try_files $uri $uri/ /index.php?$query_string;
}
location /api/v0 {
try_files $uri $uri/ /api_v0.php?$query_string;
}
location ~ \.php {
include fastcgi.conf;
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass unix:/var/run/php-fpm/php-fpm.sock;
}
location ~ /\.ht {
deny all;
}
}Nginx Configuration with SSL
server {
listen 80;
server_name librenms.example.com;
root /opt/librenms/html;
return 301 https://$server_name$request_uri;
}
server {
listen 443 ssl http2;
server_name librenms.example.com;;
root /opt/librenms/html;
index index.php;
# Set Logs path
access_log /var/log/nginx/access.log;
error_log /var/log/nginx/error.log;
# Configure SSL
ssl_certificate /etc/letsencrypt/live/librenms.example.com/fullchain.pem;
ssl_certificate_key /etc/letsencrypt/live/librenms.example.com/privkey.pem;
# Enabling Gzip compression on Nginx
charset utf-8;
gzip on;
gzip_types text/css application/javascript text/javascript application/x-javascript image/svg+xml text/plain text/xsd text/xsl text/xml image/x-icon;
location / {
try_files $uri $uri/ /index.php?$query_string;
}
location /api/v0 {
try_files $uri $uri/ /api_v0.php?$query_string;
}
# PHP-FPM handle all .php files requests
location ~ \.php {
include fastcgi.conf;
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass unix:/var/run/php-fpm/php-fpm.sock;
}
location ~ /\.ht {
deny all;
}
}
Confirm nginx syntax:
$ sudo nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successfulIf all looks good, restart the service
sudo systemctl restart nginxConfigure cron jobs
sudo cp /opt/librenms/librenms.nonroot.cron /etc/cron.d/librenmsCopy logrotate config
LibreNMS keeps logs in /opt/librenms/logs. Over time these can become large and be rotated out.
To rotate out the old logs you can use the provided logrotate config file:
sudo cp /opt/librenms/misc/librenms.logrotate /etc/logrotate.d/librenmsSet proper permissions
sudo chown -R librenms:nginx /opt/librenms
sudo chmod -R 775 /opt/librenms
sudo setfacl -d -m g::rwx /opt/librenms/logs
sudo setfacl -d -m g::rwx /opt/librenms/rrd /opt/librenms/logs /opt/librenms/bootstrap/cache/ /opt/librenms/storage/
sudo setfacl -R -m g::rwx /opt/librenms/rrd /opt/librenms/logs /opt/librenms/bootstrap/cache/ /opt/librenms/storage/Start LibreNMS Web Installer
Open http://librenms.example.com/install.php on your web browser to finish the installation.
Confirm that all Pre-Install Checks passes and click “Next Stage”
Configure Database credentials as created earlier. It will start to import database schema and populate data.
On the next page, you’ll be asked to configure admin user account.
Username: admin Password: StrongPassword
Next is the generation of the configuration file, you may have to create the file manually with the contents given if it fails to create. The file path should be /opt/librenms/.env.
$ sudo vim /opt/librenms/.env
# Database connection settings
DB_HOST=localhost
DB_DATABASE=librenms
DB_USERNAME=librenms_user
DB_PASSWORD=Password1234!Change ownership of the file to a librenms user:
sudo chown librenms:librenms /opt/librenms/.envClick “Finish Install” button to complete LibreNMS installation on CentOS 7
You should be greeted with an admin login page. Login and select Validate Installation
We also have other monitoring tutorials around Zabbix, Grafana, Prometheus, and InfluxDB.
