nagios service check example nagios service check example

I wouldn't leave this setting on normally though, it is very verbose and fills your log file at a rapid rate. NSClient++ allows you to check multiple services, here is an example that checks for two services that are running. The plugins can be in any language, Nagios only cares They can be the following: 0: OK Passive checks are performed by external processes and the results are given back to Nagios for processing. Method 2. By default you do not need to change any of the lines in this file and . The line should look like: Define the standard checks that you will perform on every client with NRPE. These checks help ensure that the dependency logic is as accurate as possible. Enjoy unlimited access on 5500+ Hand Picked Quality Video Courses. Current status from nagios Web interface: Thank you article really help a beginer like me ;-). This mechanism includes password protection, along with encryption, to prevent injection of false results in to Nagios. Thanks for contributing an answer to Server Fault! Unlike with active host checks, Nagios does not (by default) attempt to determine whether or host is DOWN or UNREACHABLE with passive checks. Always remember, prior to reloading Nagios, check that there are no errors in the configuration. See Also: Active Checks, Service Checks, Host Checks. As the Nagios toolsets, including NSCA (Nagios Service Check Acceptor for submitting passive check results to the Nagios core server) and NRPE (Nagios Remote Plugin Executor for accepting active check requests from the Nagios core server and send back the results), were initially only developed for Unix-based and Linux Operating Systems, (In this example, the script will print All ok and it will exit with 0, the OK . . These checks are scripts and progams which take input (for example, which host to check, tresholds), do a check and then return an exit code and some performance data. This article assumes you have a working knowledge of Nagios. Another difference is that active checks require much less effort to be set up when compared to passive checks. If youve installed Nagios from source, check_httpd command will be located in the /usr/local/nagios/libexec directory. Now let us add check_interval directive. NRDP has several benefits over NSCA, including: In other cases, passive checks are the way to go. 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. Once again, we are dealing with open source software, and Nagios purpose is aimed at monitoring computer systems. check_http -H hostname (or) -I ip-address {optional options}. NPCA includes a service module that can check if a service is stopped. It is vital to make sure only legitimate networks have access to the database. You have entered an incorrect email address! nagiostats provides statistics of which only the part `Services Ok/Warn/Unk/Crit: 8 / 0 / 0 / 0` are interesting to us, so we are using grep to extract this line. Here is my configuration : And in Puppet agent, I have to define the environment (Dev, Test or Prod). Each server runs one or more common services. It allows to configure alerts and has different states for them. You need to add the full path to it in the check_command. It can be used to send results from one Nagios instance to another. 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. Previous parts of this book often mentioned Nagios performing checks on various software and machines. debug_level=2048 With nagios in debug mode I simply tail the debug_log file debug_file=/var/log/nagios3/nagios.debug. There are no attachments for this article. The module can only check if the service is started, you could however use the negate plugin to invert the returned result from the plugin (hence making CRITICAL an OK state). Nagios allows applications and event handlers to send out passive check results for host objects. This yields less output to dig through. If up-to-date information has been provided by a passive check during this period, then it will not perform active checks. -c 7 -w 5 -v. Any pointer if I am missing anything but obvious. # SAMPLE HOST CHECK . # Sample object config file for Nagios : 3 # 4 # Read the documentation for more information on this configuration file. The first parameter tells Nagios that it should check whether the results from the checks are up-to-date. Hi, thanks for your comment. This should enable MySQL to listen on all interfaces, as well as accept incoming connections from user nagios at any host. Nagios' check_ssh (of course) keeps marking the process as critical since it can't connect on that port. When you restart the Nagios, this host will start getting monitored by Nagios and the specified services will run. Here is another example to check CPU: nagios will indicate warning if the % cpu utilized by any process is greater than 70% and will indicate critical alert if the % cpu is greater that 80% This is how your host definitions look currently . 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. Simple invoke the command with -s parameter and the name of the service Example of use ./check_service -s ntpd Thank you! Check whether Apache HTTP is running on a remote server using check_http. NSClient++ includes a service module that can check if a service is running. If you are new to the Nagios network monitoring system, see the resources at the Nagios website. A good example of such a test is checking whether there are bad blocks on a disk. Nagios can tell what the status of the service is by reading the exit code of the check. Nagios can monitor different mail server components like SMTP, POP, IMAP and mailq. Nagios Core and Nagios XI has a features to monitoring website URL status. You know the basics on Nagios administration. The documentation uses the example of: for . 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Ensure that the local file and .d directory are included in the main configuration file with: Now check one of the previously defined NRPE commands from the Nagios server: Note that the check_users NRPE command was defined in the /etc/nagios/nrpe_local.cfg file to run /usr/lib/nagios/plugins/check_users -w 5 -c 10. Furthermore , Nagios can also check whether TCP port 80 (web server) is reachable e.g., the server is online but Apache/IIS is not responding. The nature of simulating nature: A Q&A with IBM Quantum researcher Dr. Jamie We've added a "Necessary cookies only" option to the cookie consent popup. First, the servers are defined in Nagios. In order to use them, the host needs to be configured to accept passive checks results. The host status code should be 0 for an UP state, 1 for DOWN and 2 for an UNREACHABLE state. Nagios, the Nagios logo, and Nagios graphics are the servicemarks, trademarks, or registered trademarks owned by Nagios Enterprises. All of the scripts are located at /etc/nagios-plugins/config/ with the executable files stored at /usr/lib/nagios/plugins/. How to tell which packages are held back due to phased updates. When Nagios checks the status of services, it will be able to detect when a service changes between OK, WARNING, UNKNOWN, and CRITICAL states and take appropriate action. Service - Started Check to see if a service is started. VS Code extension | 35 comentarios en LinkedIn In this example we are going to define a service and assign it to localhost, because this check is on Nagios itself. In cases where the checks require the deployment of long-running processes or monitoring information constantly, this should be done as a passive service. Follow Up: struct sockaddr storage initialization by network format-string, Identify those arcade games from a 1983 Brazilian music video. They may or may not work on: 44 # your system, as they must be modified for your plugins. If you would like to use the whole or any part of this article, you need to cite this web page at Xmodulo.com as the original source. Complete a blank sample electronically to Thus, the difference between active and passive check is that active checks are run by Nagios and passive checks are run by external applications. We make use of First and third party cookies to improve our user experience. The following screenshot shows a complete overview of all the service checks that have been configured so far. The files and information on this site are the property of their respective owner(s). 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. The Nagios passive check technique described in this article uses Nagios Service Check Acceptor (NSCA) . You'll see the following line inside the /etc/rc.d/init.d/nagios script for the Nagios startup: $NagiosBin -d $NagiosCfgFile Nagios comes with a wide range of built-in scripts for monitoring services. Some of the scripts provided with Nagios are restricted to the local server only. does the HTML display xx welcome xx? Remember to allow the execution of the script: if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[300,250],'howtoforge_com-box-4','ezslot_6',110,'0','0'])};__ez_fad_position('div-gpt-ad-howtoforge_com-box-4-0'); The result is a text message and an exit code: This step will be the same with your own plugins, and if you download a third-party plugin from the internet as well. just because i had already looked in the commands.cfg file to figure out which commands were running, but i wanted to know what flags were being set. Check WMI Plus allows you to check multiple services, here is an example that checks for two services that are running. Add the file to the standard Nagios Core location, /usr/local/nagios/libexec. Once the host and services are configured on Nagios, checks are used to see if the hosts and services are working as they are supposed to or not. The plugin can only check if the service is started, you could however use the negate plugin to invert the returned result from the plugin (hence making "stopped" have an OK state). This is where the location of Nagios log file, status.dat file, lock file and host and services state update interval is defined. As this tutorial is based on Debian 9, I will show as an example how to install it, but you can find instructions for any distribution. Passive checks are initiated and performed by external applications/processes, Passive check results are submitted to Nagios for processing, Asynchronous in nature and cannot be monitored effectively by polling their status on a regularly scheduled basis, Located behind a firewall and cannot be checked actively from the monitoring host. In order to allow remote hosts to send passive check results to the monitoring host, I've developed the NSCA addon. 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 I just used that simple script as an example, any language can be used to write your own custom plugin. Enjoy unlimited access on 5500+ Hand Picked Quality Video Courses. # Defaults to 0, put to 1 for systemd. Nagios Plugins does not include a service plugin however the linux-nrpe-agent does provide check_init_service. . Add the command to the NRPE configuration file on the client (/etc/nagios/nrpe_local.cfg): Now we can access the server and test it like any standard plugin. 164060 Nagios HTTP/HTTPS check via wget (with/without Proxy) Check website accessibility by return code and execution time. You can create a host file inside the server directory of Nagios and mention the host and service definitions. ##### ##### # # SAMPLE SERVICE CHECK COMMANDS # # These are some example . It can test normal (http) and secure (https) servers, follow redirects, search for strings and regular expressions, check connection times, and report on If you preorder a special airline meal (e.g. The results are passed to Nagios in the same way as they are passed for hosts. These checks are useful when you cannot monitor hosts/services on a regular basis. Add additional tags that should be sent in the HTTP header. NSClient++ includes a service module that can check if a service is running. How to Install Nagios? This tutorial was tested using Nagios Core 4.3.4 on Debian 9.2if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[300,250],'howtoforge_com-box-3','ezslot_3',106,'0','0'])};__ez_fad_position('div-gpt-ad-howtoforge_com-box-3-0'); Even though Nagios Exchange has thousands of available plugins to freely download, sometimes the status needed to be checked is very specific for your scenario. Start Nagios Daemon Using nagios -d Typically you would execute "service nagios start" to start the Nagios daemon, which really calls the /etc/rc.d/init.d/nagios script. This can be done to gather all critical errors to a single, central place. It can also send reports after a database recovery, or periodically, even if connectivity to the database has been consistently available, so that Nagios has an up-to-date status. 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. The NRDP addon allows administrators to migrate from using NSCA to NRDP fairly easily. My code is GPL licensed, can I issue a license to have my code be distributed in a specific MIT licensed project? Checking a service using SNMP is not very straight forward, checking a process is the best solution here, please refer to the Process Checks KB article. 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 . Submitting Passive Host Check Results External applications can submit passive host check results to Nagios by writing a PROCESS_HOST_CHECK_RESULT external command to the external command file. The method for using any of these "plugins" from the command line is the same as any other Linux script: Just run "./plugin-name" with the appropriate flags you want to check, and voila! The performance of on-demand service checks can be significantly improved by implementing the use of cached checks, which allow Nagios to forgo executing a service check if it determines a relatively recent check result will do instead. Default is 10 seconds. 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. If you don't make use of service dependencies, Nagios won't perform any on-demand service checks. @sunardo I just ran into this exact same thing. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. Nagios server in this example is hosted on 192.168.0.150 and an example client is hosted on IP 192.168.0.200. In most cases you'll use Nagios to monitor your hosts and services using regularly scheduled active checks. /usr/lib/nagios/plugins/check_nrpe -H 3.6.123.156 -c check_root_home_du. As an example of the use of this script, the command that is sent to Nagios for host01, service PING, status code 0 (OK) and output RTT=57 ms is as follows: A very common scenario for using passive checks is a check that takes a very long time to complete. If you want know more, just read and play with: I'm new to shell and would like to understand and adapt your script would you comment on why this particular adaptation wont work (results unknown - 0 regardless of input parameter sent by the user), countWarnings=$(/usr/local/nagios/bin/nagiostats | grep "Ok/Warn/Unk/Crit:" | sed 's/[[:space:]]//g' | cut -d"/" -f5), echo "example: plugin.sh minimal_counter_for_warning_alert counter_for_critical_alert", if (($warn<=$countWarnings ||$countWarnings==0)); then, echo "OK - $countWarnings services in Warning state", elif (($warn<$countWarnings && $countWarnings<=$crit)); then, echo "WARNING - $countWarnings services in Warning state", echo "CRITICAL - $countWarnings services in Warning state", [emailprotected]:/usr/local/nagios/libexec$ echo $(/usr/local/nagios/bin/nagiostats | grep "Ok/Warn/Unk/Crit:" | sed 's/[[:space:]]//g' | cut -d"/" -f5). nagiosrpm. The external application writes the results of the check to the. This is the main configuration file of Nagios core. The service check runs in a child process that was fork()ed from the main Nagios daemon. More information on the NSCA addon can be found here. I've # provided some comments here, but things may not be so clear without further # explanation, so make sure to read the HTML documentation! Scheduled service checks are run in parallel. To identify the status of a monitored service, Nagios runs a check plugin on it. We can also configure Nagios so that if no new information has been provided within a certain period of time, it will use active checks to get the current status of the host or service. Passive checks are also used when configuring distributed or redundant monitoring installations. But if you just want to check if the instance is up and running (and not add more complexity), you can use the simple script provided here. I've: 5 # provided some comments here, but things may not be so clear without further . These plugin states directly translate to service states. 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. Last updated on September 22, 2020 by Sarmed Rahman. What can a lawyer do if the client wants him to be acquitted of everything despite serious evidence? How to install and configure Nagios Core. /usr/nagios/libexec/check_http .. Nagios understands the following exit codes: A program can be written in any language to work as a Nagios check plugin. Filters such as firewall and TCP wrappers should be used. Often, there are situations where active checks obviously fit better. An external application checks the status on hosts/services and writes the result to External Command File. As mentioned earlier, Nagios can forgo the actual execution of an on-demand service check if it can use the cached results from a relatively recent service check. This way, the other applications on your Nagios server can report the status of the hosts. How to install and configure nagios on centos 7 step by step ile ilikili ileri arayn ya da 22 milyondan fazla i ieriiyle dnyann en byk serbest alma pazarnda ie alm yapn. Service state changes can also trigger on-demand host checks. For example, to set up a very similar service, all we need to do is to use the same parameters as those for the hosts: In this case, Nagios will never perform any active checks on its own and will only rely on the results that are passed to it. >Mainly Focus on Kafka and Cloudera services, Cluster . This will give an idea on whether the execution will be successful and what the output of the script will look like. These are real-time graphs showing things like CPU usage, memory usage, and bandwidth. Otherwise we must rely on parsing the # output from the service management tool. Affordable solution to train a team and make them project ready. The default FQDN used for testing is www.google.com, but it can be changed as needed. For example . Nagios provides a sample configuration file, that we will use. The flexibility provided by Nagios is perfect for these case scenarios. Stop once the headers are downloaded. Even if its parent host is currently DOWN, the child host state is also stored as DOWN. Nagios also offers a tool for sending passive check results for hosts and services over a network. To figure this out I set nagios into debug mode with the configuration like this. Securely download your document with other editable templates, any time, with PDFfiller. Pass the specified string as User Agent in HTTP header. You can define service execution dependencies that prevent Nagios from checking the status of a service depending on the state of one or more other services. In this way, NSCA communication sent over the Internet is more secure. Let us assume that the following custom application is also running in the network, listening on a particular port. Nagios Enterprises makes no claims or warranties as to the fitness of any file or information on this website, for any purpose whatsoever. i'm very new on that kind of progamming what does this line ", " means i really want to lear some but i need help please helpme. Nagios executes event handlers to handle hard states. Use Hiera. The following file can be modified to do the job. Kaydolmak ve ilere teklif vermek cretsizdir. The figure shown below shows an active check . To learn more, see our tips on writing great answers. I Have problem with the check_http when I try ur command test , I have the next message : Passive service checks are often used to report the results of long lasting tests asynchronously. . Now that the syntax is available, TCP port 80 can be checked as follows. It is possible to monitor machine metrics, such as disk usage, CPU use, and so on. On the client host that you want to use to connect to remote Docker daemon, generate SSH keys from your user account; ssh-keygen. The daemon will listen for connections from remote clients, perform some basic validation on the results being submitted, and then write the check results directly into the external command file (as described above). In such a case, adding a module that reports current utilization along with the OK/WARNING/CRITICAL state to Nagios seems much easier than using active checks for the same job. I am running into the same problem as David 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. The NSCA addon consists of a daemon that runs on the Nagios hosts and a client that is executed from remote hosts. So I decided to use the second method. NPCA includes a service module that can check if a service is running. 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. How to use it? This command accepts the host name, service description, status code, and the textual output from a check. Consider that you have put your host definitions inside host1.cfg file in /usr/local/nagios/etc/objects directory. Let us see an example to perform checks on host Consider that you have put your host definitions inside host1.cfg file in /usr/local/nagios/etc/objects directory. To allow it to grow bigger before rotating, add more zeroes, for example. NSCA stands for Nagios Service Check Acceptor. If an application that resides on the same host as Nagios is sending passive host or service check results, it can simply write the results directly to the external command file as outlined above. So in the server set the files: /usr/local/nagios/etc/objects/commands.cfg: /usr/local/nagios/etc/objects/nrpeclient.cfg: Note that the ! One of the problems is that such checks can take only a couple of seconds to completea typical timeout for an active check to complete is 10 or 30 seconds. More information on the flap detection logic can be found here. # yum -y install httpd gcc glibc glibc-common gd gd-devel openssl-devel net-snmp net-snmp-devel net-snmp-utils snmp* bc xinetd make wget (php php-mysql) . rev2023.3.3.43278. On a finishing note, Nagios can monitor many other sectors of a network. Yup, just like any other linux flag, the "-" with whatever flags you use will load the flag. The following illustration shows how results from active and passive checks are treated differently by Nagios: In both the cases, a check result stating that the host is down is received by Nagios. It's pretty simple. To check whether a specific webpage is available, use the -u option as shown below. 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.