However, if there are no jobs to process and the application is not using it, Nagios will not have up-to-date information about the database. This means that if Nagios receives a result indicating that a host is DOWN, it assumes that all child hosts are in an UNREACHABLE state. The Nagios server is running on Ubuntu. Copy the configuration file to the Apache directory: /usr/bin/install -c -m 644 sample-config/httpd.conf /etc/apache2/sites-available/nagios.conf Install the Nagios Plugins to have a set of tools to monitor your different services: apt install build-essential libssl-dev gcc Host is just like a computer; it can be a physical device or virtual. Nagios Plugins Nagios Plugins does not include a service plugin however the linux-nrpe-agent does provide check_init_service. When new information regarding a service gets passed to Nagios via the external commands pipe, Nagios treats it the same way as if it had been received by an active check. The plugin returns a CRITICAL state if the service is not started. Another difference is that active checks require much less effort to be set up when compared to passive checks. When a host or service is down for a very short duration of time and its status is not known or different from previous one, then soft states are used. NPCA includes a service module that can check if a service is running. As mentioned earlier, server-2 has postfix mail server set up on it. If you don't make use of service dependencies, Nagios won't perform any on-demand service checks. Note: A host must be defined in Nagios before you can submit passive check results for it! Now we know that the custom plugin is working on the client and on the server, and that the NRPE is communicating correctly, we can go ahead and configure Nagios files for checking the remote device. Nagios allows applications and event handlers to send out passive check results for host objects. Here is an example set of passive checks that . I am running into the same problem as David This should enable MySQL to listen on all interfaces, as well as accept incoming connections from user nagios at any host. If you want Nagios to treat all passive check results for hosts as if they were soft results, you need to enable the following option in the main Nagios configuration file: Passive service checks are very similar to passive host checks. When everything goes smoothly, we should be able to see our new Nagios client on the Nagios website with its new service OS: unread mail for root, as well as the status green OK. Note that all the configuration in this section is done on the client to be checked, not in the nagios server. (In this example, the script will print All ok and it will exit with 0, the OK . Apply these agent configurations After the NRDP installation, install the NCPA. will hold the return value of commands between $( ). You never know how many (if any) traps or alerts you'll receive in a given time frame, so it's not feasible to just monitor their status every few minutes. How can I manually run a nagios check from the command line? $ check_http -H 192.168.1.50 HTTP OK HTTP/1.1 200 OK - 332 bytes in 0.004 seconds |time=0.004144s;;;0.000000 size=332B;;;0 2. Like every Nagios plugin, you will want to check from the command line before adding it to the configuration files. The output indicates that it expires in 300 days. Service state changes can also trigger on-demand host checks. can nagios adjust its check time based on the status info? Nagios, NagiosXI, Nagios Core, Nagios Logger, Manage Engine, Idera, Quest, Thousand Eyes Idera Suite and Quest, SQL Monitoring Solution Implementation Add the file to the standard Nagios Core location, /usr/local/nagios/libexec. How can I get it to work with https with Nagios4 and plugins 2.x? What you are doing down is sending a Passive check result for the service SNMP Traps - Users for the host CentOS. The following is an example of the required configuration for a host that accepts passive checks and has active checks disabled: define host { use generic-host host_name linuxbox01 address 10.0.2.1 As with passive checks of hosts, all that is needed is to enable the global Nagios option to accept passive check results, and also enable this option for each service that should allow the passing of passive check results. Complete a blank sample electronically to Nagios can tell what the status of the service is by reading the exit code of the check. Nagios's primary mode of "service checking" is called an active check. It is a protocol that is used in reverse of the other common Nagios protocol NRPE. NSClient++ includes a service module that can check if a service is running. Services are checked by the Nagios daemon: At regular intervals, as defined by the check_interval and retry_interval options in your service definitions. I wouldn't leave this setting on normally though, it is very verbose and fills your log file at a rapid rate. define service{ use generic-service host_name web1.onemetric.com.au service_description Uptime check_command snmp_Uptime!-C public } Adjust the commands as required. NPCA includes a service module that can check if a service is stopped. Let's consider I have the Nagios server configured to alert only on critical status, so I want an alert if I have too many services on a Warning status. Up To: Contents The flexibility provided by Nagios is perfect for these case scenarios. The object needs to have the passive_checks_enabled option set to 1 for Nagios to accept passive check results over the command pipe. In the first case, Nagios takes care of the scheduling, and the command only needs to perform the actual checks and mark the results as OK/WARNING/CRITICAL based on how a check command is configured. An example shell script of how to submit passive service check results to Nagios can be found in the documentation on volatile services. This setting will expose MySQL to all available interfaces, including WAN. The plugins can be in any language, Nagios only cares They can be the following: 0: OK On the next screen: Enter a unique name in the Command Name field (suggest one is check_host_cluster and the other check_service_cluster) Append --host to the Command Line section for host . Nagios Plugins does not include a service plugin however the linux-nrpe-agent does provide check_init_service. You can submit passive (means Nagios is not the inventor of the actual check commands) check results to a Nagios server instead of having the Nagios actively polling. How Nagios process handles passive check results can be defined in the main Nagios configuration file. The Nagios Service Check Acceptor (NSCA ) addon has historically been the addon of choice for Nagios administrators that need to establish data feeds or passive check transmission between Nagios installations. Expected response string. Nagios, the Nagios logo, and Nagios graphics are the servicemarks, trademarks, or registered trademarks owned by Nagios Enterprises. Yeah, it's totally brute-force, but it works for me. For those unfamiliar with Nagios, it is a monitoring system which can execute checks. The check_init_service plugin does not support checking multiple services. A user nagios is created for both localhost and for any host. Please refer tohttp://tldp.org/LDP/abs/html/untyped.html, hi! Fortra's Intermapper vs Kaseya Traverse: which is better? These types of checks are called Active Checks. Each of these options opens the Manage Service Template screen.The New option will have no pre-selected directive values, Copy lets you create a new template based on an existing templates properties, and Modify enables the editing of an . The command to submit passive checks is PROCESS_HOST_CHECK_RESULT (visit http://www.nagios.org/developerinfo/externalcommands/commandinfo.php?command_id=115). Force a check and you will see exactly how the command is being run. Base your decision on 2 verified in-depth peer reviews and ratings, pros & cons, pricing, support and more. In this tutorial, we'll install Nagios on an Ubuntu 19.10 server, but these steps should work on any Debian-based distro. you have the flexibility of sending the passive check to Nagios with a different hostname. check_http -H hostname (or) -I ip-address {optional options}. Periodically when these checks are processed, notifications or alerts are sent depending on the information in check result. This is a plugin for Nagios wich you can use to check if a linux service is running. This website is made possible by minimal ads and your gracious donation via PayPal or credit card. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. When it comes in as a passive check, no state translation is done and Nagios stores the host and all child nodes being down. Note: A service must be defined in Nagios before you can submit passive check results for it! Or you can create a custom variable to store the port number , with your example: Depending on the status received on hosts and services, appropriate action is taken. However, two hours after the last passive or active check result was received, Nagios would perform an active check to keep the results up-to-date. Nagios: Disable notifications from command line on Windows/Linux. Can i specify what a valid response is, i.e. To check whether a specific webpage is available, use the -u option as shown below. Line 1 ##### 2 # Sample object config file for Nagios : 3 # 4 # Read the documentation for more information on this configuration file. # Sample object config file for Nagios : 3 # 4 # Read the documentation for more information on this configuration file. To use a custom script as a plugin to run remotely through NRPE, you should first write the script on the server, for instance in /usr/local/scripts/check_root_home_du.sh: The previous script is a very simple example, checking the disk usage of the directory /root and setting a threshold for considering it OK, Warning or Critical. This is where the location of Nagios log file, status.dat file, lock file and host and services state update interval is defined. When Nagios plans and receives results from active checks, it takes the actual network topology into consideration and performs a translation of the states based on this. In fact, we officially. In both the cases, the idea is that Nagios receives information about host statuses over the external commands pipe. Services are those which are used by Nagios to check something about a host. So if you wanted to run the check_http check from the CLI, you would run ./check_http -I, where the I flag stands for the IP Address (, I struggled to get this to work, not sure what i was doing wrong (noob) but the debug_level trick worked for me :). You do this with nagios -v command as root: Ensure it returns 0 errors and 0 warnings and proceed to reload the service: After reloading the service, you will see the associated check in the localhost. While Nagios can monitor multiple OSes, the server must reside on a Linux or Unix variant such as FreeBSD or Solaris. When it comes to checking MySQL, it should be kept in mind that MySQL, by default, listens on only the loopback interface 127.0.0.1. Hosts and service configurations are the building blocks of Nagios Core. There are many more services in Nagios which can be used to monitor pretty much anything on the running host. When a host is reported to be DOWN as a passive check result, Nagios does not perform a translation from DOWN to UNREACHABLE. does the HTML display xx welcome xx? Xmodulo 2021 About Write for Us Feed Powered by DigitalOcean, Creative Commons Attribution-ShareAlike 3.0 Unported License, Monitor whether MySQL is running by checking port, Monitor the availability of certain database. 2. Services are those which are used by Nagios to check something about a host. How to handle a hobby that makes income in US. Follow these steps to install the plugin: Download the plugin. You can create a host file inside the server directory of Nagios and mention the host and service definitions. Do whatever you want with a Deploying Nagios Monitoring Services on Secured Red Hat Enterprise Linux 3 Environment: fill, sign, print and send online instantly. If youve installed Nagios from source, check_httpd command will be located in the /usr/local/nagios/libexec directory. Stats Graphs - Live data graphs of CPU, memory, interface bandwidth, and disk usage. host_name Server01 We make use of First and third party cookies to improve our user experience. On any device & OS. Edit the /usr/local/nagios/etc/objects/localhost.cfg file and add the following block: Now we are all set, the only thing pending is reloading Nagios to read the configuration files again. In order to allow remote hosts to send passive check results to the monitoring host, I've developed the NSCA addon. They are a web interface and command line tool set to work with Nagios config that have decent default templates and "example" files that you can leverage for common checks. When the service check has completed, the child process will inform the main Nagios process (its parent) of the check results. Now that the syntax is available, TCP port 80 can be checked as follows. Nagios server in this example is hosted on 192.168..150 and an example client is hosted on IP 192.168..200 Exit Codes To identify the status of a monitored service, Nagios runs a check nagios.cfg. The application can also periodically let Nagios know if it succeeded in using the database without problems. By default you do not need to change any of the lines in this file and . Repeat this procedure for each Ceph plug-in applicable to the node. The following diagram shows how both active and passive checks are performed by Nagios. You might also want to give the 'capture' plugin a try. Related Commands. When you restart the Nagios, this host will start getting monitored by Nagios and the specified services will run. Is there a more efficient way to do this? I just used that simple script as an example, any language can be used to write your own custom plugin. Set enable_notifications=0 in nagios.cfg. (1)Nagios. In such cases, only reports regarding hard state changes are propagated across Nagios servers. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Monthly digest of what's new and exciting from us. Nagios also supports a way to monitor hosts and services passively instead of actively. The main Nagios process then handles the check results and takes appropriate action (running event handlers, sending notifications, etc.). Also, MySQL would not let just any host to connect to it.