1. The Necessity of Using Nagios
1. Managing a large amount of IT infrastructure is tedious and complex.
2. Reduces management and maintenance costs
3. Optimizes systems and rationally utilizes service resources
Monitoring Software Limitations:
1. No single tool can monitor absolutely everything you need.
2. Significant customization is required to make a tool fully adapt to your needs.
2. What is Nagios
Nagios鈥擭agios Ain’t Gonna Insist on Sainthood
The original project name was NetSaint, and the main program is written in ANSI C.
Nagios is an open-source, free network monitoring tool that is powerful and highly flexible. It can effectively monitor the status of Windows, Linux, and Unix hosts, network devices like switches and routers, printers, and more. When a system or service status is abnormal, it sends email or SMS alerts to notify website operations personnel immediately. After the status returns to normal, it sends a corresponding normal notification.
?Commercial IT management systems, such as IBM Tivoli, HP OpenView/Operations, etc.
?Official site: http://www.nagios.org/
?
3. The Structure of Nagios
Nagios can be divided into two parts: the core and plugins.
The core part of Nagios provides only a few monitoring functions. Therefore, to build a comprehensive IT monitoring and management system, users need to install corresponding plugins for Nagios. Plugins can be downloaded from the Nagios official website, or you can write the required plugins yourself according to actual requirements.
Nagios must run on a Linux/Unix platform and requires a gcc compiler. Nagios also provides a web monitoring interface.
4. Functions that Nagios Can Achieve
(1) Monitor local or remote host resources (memory, processes, disks, etc.)
(2) Monitor network service resources (HTTP, PING, FTP, SMTP, POP3, etc.)
(3) Allows users to write their own plugins to monitor specific services.
(4) When a monitored object is abnormal, it can notify management personnel via email, SMS, etc.
(5) Event handlers can be defined in advance, automatically calling specified handler programs when a host or service fails.
(6) The running status of various hosts or services can be monitored through a web interface.
5. Implementation Principle of Nagios Monitoring
Nagios software needs to be installed on a dedicated server to run. This server is called the monitoring center, and it can use a Linux or Unix operating system. Each hardware host or service that needs to be monitored runs a Nagios software background program that communicates with the monitoring center server. The monitoring center server reads instructions from configuration files to communicate with the remote daemon programs and instructs the remote daemon programs to perform necessary checks.?