Nagios memory monitoring error under Linux How to set up email sending in nagios

Nagios is an open source free network monitoring tool that can effectively monitor the host status of Windows, Linux and Unix, network settings such as switches and routers, printers, etc. When the system or service status is abnormal, an email or SMS alarm will be sent to notify the website operation and maintenance personnel immediately, and a normal email or SMS notification will be sent after the status is restored.

Note:

● Host name host_name must be the host defined in the host configuration file hosts.cfg.

● The check_command command is defined in the command configuration file or in the nrpe configuration file.

● The maximum number of retries max_check_attempts is generally set to 3-4 times, so that false alarms will not occur due to network interruptions for a moment.

● The unit of check interval and retry check interval is minutes.

● The notification interval refers to the interval at which alarm information is sent after a fault is detected. Its unit is minutes.

● Notification options are the same as the service definition configuration file.

● Contact group contact_groups is defined by the configuration file contactgroup.cfg.

● Checking host resources requires installing and configuring nrpe, which will be completed later.

The functions that Nagios can monitor are:

1. Monitor network services (SMTP, POP3, HTTP, NNTP, PING, etc.);

2. Monitor the host Resources (processor load, disk utilization, etc.);

3. Simple plug-in design allows users to easily expand their own service detection methods;

4. Parallel service inspection mechanism ;

5. Have the ability to define the network hierarchical structure. Use "parent" host definition to express the relationship between network hosts. This relationship can be used to discover and clarify host downtime or unreachable status. ;

6. When service or host problems occur and are resolved, alarms will be sent to contacts (via EMail, SMS, user-defined methods);

7. Some handlers can be defined , so that it can play a preventive role when the service or host fails;

8. Automatic log rolling function;

9. Can support and implement redundant monitoring of the host ;

10. The optional WEB interface is used to view the current network status, notification and fault history, log files, etc.;

11. System monitoring information can be viewed through the mobile phone;< /p>

12. Custom event processing controller can be specified;