Nagios is the most widely used open source monitoring tools which help us to monitor the services and application that run’s on Windows, Linux, Routers and other network devices.
With the help of Nagios, you can monitor basic services and attributes. We can access the Nagios using web interface coming with the bundle and configuration need to be done on the file level.
What’s New
- Core Workers are the lightweight process whose job is to perform checks, due to this they do perform checks much more quickly than the old process.
- Nagios Core process using in-memory techniques, eliminating the disk I/O latencies that could previously slow things down in a large installation.
- Each configuration item is verified only once.
- The host address attribute is now optional.
- Bothe hosts and services now support an hourly value attribute.
More feature can be found here.
Services List
This Tutorial describes how you can monitor “private” services and attributes of Linux/UNIX servers, such as:
Attributes
- CPU load
- Memory usage
- Disk usage
- Logged in users
- Running processes
- etc.
Private Services
- HTTP
- FTP
- SSH
- SMTP
- etc
Prerequisites
Before installing the Nagios, the system needs to meet the requirements for installing Nagios. So install the Web Server (httpd), PHP, compilers and development libraries.
Install all packages in a single command.
yum -y install httpd php gcc glibc glibc-common wget perl gd gd-devel unzip zip
Create a nagios user and nagcmd group for allowing the external commands to be executed through the web interface, add the nagios and apache user to be a part of the nagcmd group.
useradd nagios groupadd nagcmd usermod -a -G nagcmd nagios usermod -a -G nagcmd apache
Download latest Nagios Core.
cd /tmp/ wget https://assets.nagios.com/downloads/nagioscore/releases/nagios-4.3.4.tar.gz tar -zxvf /tmp/nagios-4.*.tar.gz cd /tmp/nagios-4.*
Compile and Install Nagios.
./configure --with-nagios-group=nagios --with-command-group=nagcmd make all make install make install-init make install-config make install-commandmode
Install & Configure Nagios Web Interface
Install the Nagios web configuration using the following command.
make install-webconf
Run the following command to install a Nagios exfoliation theme
make install-exfoliation
Create a user account (nagiosadmin) for logging into the Nagios web interface. Remember the password that you assign to this user – you’ll need it later.
htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin
Restart Apache web server to make the new settings take effect.
systemctl restart httpd.service systemctl enable httpd.service
Configure Nagios
Sample configuration files have now been installed in the /usr/local/nagios/etc directory. These sample files should work fine for getting started with Nagios. You’ll need to make just one change before you proceed…
Edit the /usr/local/nagios/etc/objects/contacts.cfg config file with your favorite editor and change the email address associated with the nagiosadmin contact definition to the address you’d like to use for receiving alerts.
vi /usr/local/nagios/etc/objects/contacts.cfg
Change the Email address field to receive the notification.
define contact{
contact_name nagiosadmin ; Short name of user
use generic-contact ; Inherit default values from generic-contact template (defined above)
alias Nagios Admin ; Full name of user
email admin@itzgeek.com ; <<***** CHANGE THIS TO YOUR EMAIL ADDRESS ******
}
Download and Install Nagios Plugins
Download Nagios Plugins to /tmp directory.
cd /tmp wget https://nagios-plugins.org/download/nagios-plugins-2.2.1.tar.gz tar -zxvf /tmp/nagios-plugins-*.tar.gz cd /tmp/nagios-plugins-*/
Compile and install the Nagios plugins.
./configure --with-nagios-user=nagios --with-nagios-group=nagios make make install
Start Nagios Server
Verify the sample Nagios configuration files.
/usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg
If there are no errors, then start the Nagios service.
service nagios start
Start Nagios on system startup.
chkconfig nagios on
SELinux
See if SELinux is in Enforcing mode.
getenforce
Put SELinux in Permissive mode or Disable it.
setenforce 0
To make this change permanent, you’ll have to modify the settings in /etc/selinux/config and reboot.
Iptables
Make sure to allow web server access through the firewall.
firewall-cmd --permanent --zone=public --add-service=http firewall-cmd --reload
Access Web Interface
Now access the Nagios web interface using the following URL. You’ll be prompted for the username (nagiosadmin) and password you specified earlier.
http://your-ip-add-ress/nagios/
Nagios console will look like below.
Click on Hosts in the left pane to get a list of systems being monitored by Nagios. We have not added any host to Nagios, So it simply monitors the localhost itself. To monitor a remote Linux system,
Click on Service in the left pane to get the status of any services that is being monitored with Nagios.
Credits: https://www.itzgeek.com/how-tos/linux/centos-how-tos/monitor-centos-7-rhel-7-using-nagios-4-0-7.html
Sem comentários:
Enviar um comentário