nagios service check example nagios service check example

NSClient++ includes a service module that can check if a service is stopped. NSCA stands for Nagios Service Check Acceptor. In order to use them, the host needs to be configured to accept passive checks results. 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% 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. The next parameter specifies the number of seconds after which Nagios should consider the results to be out of date. Far better then Nagios documentation. When services change state too frequently they are considered to be "flapping". 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. can nagios adjust its check time based on the status info? 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. In order to make Nagios treat passive host check results in the same way as active check results, we need to enable the following option: By default, Nagios treats host results from passive checks as hard results. Set enable_notifications=0 in nagios.cfg. This task is really easy as Nagios has a built-in command for this. We make use of First and third party cookies to improve our user experience. This is a plugin for Nagios wich you can use to check if a linux service is running. More information on the NSCA addon can be found here. Nagioshttpdgccgd. 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 results are passed to Nagios in the same way as they are passed for hosts. It allows to configure alerts and has different states for them. Now that the syntax is available, TCP port 80 can be checked as follows. All of the scripts are located at /etc/nagios-plugins/config/ with the executable files stored at /usr/lib/nagios/plugins/. 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. See the HTML : 45 Hi, thanks for your comment. An external application checks the status on hosts/services and writes the result to External Command File. # SAMPLE HOST CHECK . A good example would be a server that is a part of an application, processing job queues using a database. In case you don't have the plugin in the Nagios server, you can install it with: So, summarizing, the NRPE will run a script in a remote host, and return the exit code to the Nagios server. # 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) . If you preorder a special airline meal (e.g. hello.. will hold the return value of commands between $( ). Nagios: Disable notifications from command line on Windows/Linux. # These are some example service check commands. These plugin states directly translate to service states. The provided scripts contain help on the syntax. We want Nagios to monitor this database, and as the application is already using it, we can add a module that reports this to Nagios. For example, you can use the 'check_http' plugin to verify that a web server is running, is returning the right text, or has an up-to-date SSL certificate. Check WMI Plus allows you to check multiple services, here is an example that checks for two services that are running. This is because, very often, passive checks are used to report host and service statuses from other Nagios instances. Nagios provides a sample configuration file, that we will use. Checking a service using SNMP is not very straight forward, checking a process is the best solution here, please refer to the Process Checks KB article. In this example we are going to define a service and assign it to localhost, because this check is on Nagios itself. It is called NSCA (Nagios Service Check Acceptor). If you want know more, just read and play with: I'm new to shell and would like to understand and adapt your script would you comment on why this particular adaptation wont work (results unknown - 0 regardless of input parameter sent by the user), countWarnings=$(/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). Stats Graphs - Live data graphs of CPU, memory, interface bandwidth, and disk usage. This way, the other applications on your Nagios server can report the status of the hosts. For Nagios to perform active checks when there is no up-to-date result from passive checks, you need to set the check_freshness directive to 1 and set freshness_threshold to the time period after which a check should be performed. Thus, the difference between active and passive check is that active checks are run by Nagios and passive checks are run by external applications. The same queue that is used for storing results from active checks is also used to store the results from passive checks. Nagios can detect when services start flapping, and can suppress notifications until flapping stops and the service's state stabilizes. Monitoring Website URL Status This article assumes you have a working knowledge of Nagios. 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. It's pretty simple. Let us see an example to perform checks on host . It essentially does the same thing as a debug level of 2048, but can be used on a per-plugin basis. The external application writes the results of the check to the. They have a lot of advantages and some disadvantages. Nonetheless, they can be tuned to match the requirements. To turn on everything you want to set debug_level=4095. debug_level=2048 With nagios in debug mode I simply tail the debug_log file debug_file=/var/log/nagios3/nagios.debug. On any device & OS. Nagios can monitor DNS service by asking the DNS server to either resolve a specific fully qualified domain name (FQDN), or by asking the server to use the dig tool. In such a case, checks are done by other programs, and their results are sent to Nagios. When the service check has completed, the child process will inform the main Nagios process (its parent) of the check results. The following settings are done for all MySQL servers. Default is 10 seconds. Can i specify what a valid response is, i.e. By using this website, you agree with our Cookies Policy. Format is minimum:maximum, Response time in seconds for warning state, Response time in seconds for critical state, Number of seconds to wait before connection times out. The sections below provide examples of how to perform these checks using different methods. Nevertheless, in response to your comment, I don't think there's an error in that, as Bash variables are untyped. Does anyone have a working example of a dependencies.cfg file for nagios? I am gettinr this error in nagios3. 03-16-2010, 10:31 AM . For example, if you are bringing down your HTTP server everyday sometime between midnight and 1:59 a.m, you can specify the above "247-except-night-12-2" timeperiod in your service definition for the check_period and notification_period as shown below for your particular service definition. This should enable MySQL to listen on all interfaces, as well as accept incoming connections from user nagios at any host. Active checks can be used to "poll" a device or service for status information every so often. Then we are removing spaces using sed and finally cut the appropriate field using cut, i this case field 5 is what we want. 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. Service state changes can also trigger on-demand host checks. These are executed on regular intervals, as defined by check_interval and retry_interval. Nagios' check_ssh (of course) keeps marking the process as critical since it can't connect on that port. It can be used to send results from one Nagios instance to another. +1 and if that seems like too much trouble you could always look at the Nagios config files to see what command and parameters need to be run. How Nagios process handles passive check results can be defined in the main Nagios configuration file. You can check tomcat server, or apache server, or glassfish, or any server that is running on a different port by speficying the port number as shown below. $ 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. Please note that this article is published by Xmodulo.com under a Creative Commons Attribution-ShareAlike 3.0 Unported License. This is the main configuration file of Nagios core. Yeah, it's totally brute-force, but it works for me. You have entered an incorrect email address! You can tell Nagios to translate DOWN/UNREACHABLE passive check result states to their "proper" state by using the translate_passive_host_checks variable. 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 usually calls for some effort. 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. As mentioned earlier, server-2 has postfix mail server set up on it. It is possible to configure Nagios so that it will receive status information sent over a command pipe. NSClient++ includes a service module that can check if a service is running. These types of checks are called Active Checks. While Nagios can monitor multiple OSes, the server must reside on a Linux or Unix variant such as FreeBSD or Solaris. 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. Are there tables of wastage rates for different fruit and veg? For instance, a model for the file could be: The idea of having that generic file is so that you can check the same on every client. Get your subscription here. Passive checks require all the logic related to what should be reported and when it should be checked to be put in an external application. If a service is set up with a max_check_attempts directive of 5, then the same number of passive check results would need to be passed in order for Nagios to treat the new status as a hard state change. thanks! /usr/lib/nagios/plugins/check_nrpe -H 3.6.123.156 -c check_root_home_du. If I used the first method, I have to keep separate site.pp for each environment. Define the checks on /etc/nagios/nrpe_local.cfg. Nagios will ignore all check results for hosts that had not been configured before it was last (re)started. Even the location of the plugins directory is in there. This command accepts the host name, status code, and the textual output from a check. Often, you have situations where other applications can report if a certain service is working properly or not. Nagios, the Nagios logo, and Nagios graphics are the servicemarks, trademarks, or registered trademarks owned by Nagios Enterprises. Kaydolmak ve ilere teklif vermek cretsizdir. I will use a simple example. The following is a script that runs the dd system command (visit http://man.linuxquestions.org/index.php?query=dd) to read an entire block device. 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. Passive Checks and NSCA (Nagios Service Check Acceptor), Technology news, insights and tutorials from Packt, Top 6 Cybersecurity Books from Packt to Accelerate Your Career, Your Quick Introduction to Extended Events in Analysis Services from Blog, Logging the history of my past SQL Saturday presentations from Blog, Storage savings with Table Compression from Blog Posts SQLServerCentral, Daily Coping 31 Dec 2020 from Blog Posts SQLServerCentral, Learning Essential Linux Commands for Navigating the Shell Effectively, Exploring the Strategy Behavioral Design Pattern in Node.js, How to integrate a Medium editor in Angular 8, Implementing memory management with Golangs garbage collector, How to create sales analysis app in Qlik Sense using DAR, http://www.nagios.org/developerinfo/externalcommands/commandinfo.php?command_id=114, ExploringForms in Angular types, benefits and differences. . It has been designed to run . Fortra's Intermapper vs Kaseya Traverse: which is better? However, in a big environment it is very likely to need some custom checks for specific uses, for instance: Checking on a certain task result, monitoring an in-house developed application, among others. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. 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. First, the servers are defined in Nagios. Hello, ask a question, check_http detect page size, page size detection value changes again, the alarm. A command to submit passive checks is PROCESS_SERVICE_CHECK_RESULT (visit http://www.nagios.org/developerinfo/externalcommands/commandinfo.php?command_id=114). From the GroundWork Monitor menu, selecting Configuration > Nagios Monitoring > Services > Service Templates presents the options New, Copy, and Modify. See Also: Active Checks, Service Checks, Host Checks. You'll see the following line inside the /etc/rc.d/init.d/nagios script for the Nagios startup: $NagiosBin -d $NagiosCfgFile Nagios server in this example is hosted on 192.168.0.150 and an example client is hosted on IP 192.168.0.200. How can we prove that the supernatural or paranormal doesn't exist? 2022 Company, Inc. All rights reserved. Server Fault is a question and answer site for system and network administrators. . The object needs to have the passive_checks_enabled option set to 1 for Nagios to accept passive check results over the command pipe. Just cd (or not) into the plugins directory (this directory location varies, depending on how you've installed it, but check /usr/local/nagios, or /usr/lib/nagios). It will give you all the available options: 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). The plugin returns a CRITICAL state if the service is not started. Find the plugin you want to run (if you're not sure, compare what you see in your plugins directory on your Linux box with the plugins located here: http://exchange.nagios.org/directory/Plugins, or try running "./plugin-name -h" to get the help info about the plugin). The NSCA addon consists of a daemon that runs on the Nagios hosts and a client that is executed from remote hosts. Check whether Apache HTTP is running on a remote server using check_http. In order to do this, we need to enable active checks by setting the active_checks_enabled option to 1 without specifying the normal_check_interval directive. The host status code should be 0 for an UP state, 1 for DOWN and 2 for an UNREACHABLE state. You can check whether a SSL certificate of the website expires within the next X number of days as shown below. Default is 80, This will use HTTPS using default 443 port. The figure shown below shows an active check . Also, MySQL would not let just any host to connect to it. How can I make Status Information for Nagios services easier to read? What can a lawyer do if the client wants him to be acquitted of everything despite serious evidence? 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 . Usually within a few seconds the full check command pops up and I then kill the while loop and run the check command. It also defines Nagios user and group under which Nagios instance is running. Learn more about Stack Overflow the company, and our products. The first parameter tells Nagios that it should check whether the results from the checks are up-to-date. Installing the Nagios Remote Plugin Executor In this lab, we will install the Nagios Remote Plugin Executor on the Nagios Core Host as well as any remote hosts on which we haven't already installed it. Remember that the $USER1$ variable, is a local Nagios variable set in the resource.cfg file, in my case pointing to /usr/local/nagios/libexec. Is it possible to check a web page through an authenticated proxy server? Nagios Core and Nagios XI has a features to monitoring website URL status. 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. This is how your host definitions look currently . Securely download your document with other editable templates, any time, with PDFfiller. 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. Is there a proper earth ground point in this switch box? But today when I am trying to post an XML message to the server, from console it works well but does not work with nrpe. This cant be done as an active check as reading the device takes a lot of time to completelarger disks might require several hours to complete. As a Cloudera Administrator and Kafka service owner, leading Kafka/flume/ZK services in WAP (Multi DC Environment), Leading TICK Stack (Influxdb) and Grafana along with Administration of ELK Stack (Elasticsearch, Logstash) and Cloudera Clusters with CI/CD approach, Automation. 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. Nagios can monitor different mail server components like SMTP, POP, IMAP and mailq. If you would like to disable passive checks for just a few hosts or services, use the passive_checks_enabled directive in the host and/or service definitions to do so. 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. The application can also periodically let Nagios know if it succeeded in using the database without problems. /usr/nagios/libexec/check_http .. After installing nagios and nagios-plugins-all (via yum), I've c.