nagios service check example

. check_http -H hostname (or) -I ip-address {optional options}. There would be many cases when the failures will happen randomly and they are temporary; hence Nagios uses states to check the current status of a host or service. Check WMI Plus includes a service module that can check if a service is stopped. The NSCA addon consists of a daemon that runs on the Nagios hosts and a client that is executed from remote hosts. NSCA stands for Nagios Service Check Acceptor. 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 This is a plugin for Nagios wich you can use to check if a linux service is running. does the HTML display xx welcome xx? Learn more about Stack Overflow the company, and our products. To turn on everything you want to set debug_level=4095. For example, a plugin which returns a WARNING state will cause a service to have a WARNING state. The following is a sample script that will accept the host name, status code, and output from a check and will submit these to Nagios: As an example of the use of this script, the command that is sent to Nagios for host01, status code 2 (UNREACHABLE) and output router 192.168.1.2 down would be as follows: When submitting results, it is worth noting that Nagios might take some time to process them, depending on the intervals between Nagios checks of the external command pipe. We make use of First and third party cookies to improve our user experience. ##### # # NAGIOS.CFG - Sample Main Config File for Nagios # # 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. This way, Nagios can help monitor the accessibility of both MySQL servers and the database stored within the servers. The line should look like: Define the standard checks that you will perform on every client with NRPE. You can tell Nagios to translate DOWN/UNREACHABLE passive check result states to their "proper" state by using the translate_passive_host_checks variable. 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. Nagios also offers a way of combining the benefits of both active and passive checks. I Have problem with the check_http when I try ur command test , I have the next message : 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. The next time Nagios reads the external command file it will place the results of all passive checks into a queue for later processing. Enter file in which to save the key (/home/nagios/.ssh/id_dsa): Enter passphrase (empty for. For those unfamiliar with Nagios, it is a monitoring system which can execute checks. External applications can submit passive host check results to Nagios by writing a PROCESS_HOST_CHECK_RESULT external command to the external command file. NRDP has several benefits over NSCA, including: The __HOST__ is a special service name, which represents the host check in Nagios. I've deployed a new instance of Nagios on a fresh install of CentOS 7 via the EPEL repository. Nagios will ignore all check results for services that had not been configured before it was last (re)started. 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). This setting is done on all MySQL servers. These types of checks are called Active Checks. Let us assume that the following custom application is also running in the network, listening on a particular port. This usually calls for some effort. It essentially does the same thing as a debug level of 2048, but can be used on a per-plugin basis. The first thing that needs to be done in order to use passive checks for your Nagios setup is to make sure that you have the following options in your main Nagios configuration file: It would also be good to enable the logging of incoming passive checksthis makes determining the problem of not processing a passive check much easier. It allows the implementation of plugins, developed by the community, or even allows us to configure our own monitoring scripts. if one of my checked systems goes down, and therefore fails a PING check, I do NOT need to be notified that a file system is unavailable, or that SSH is down, too. Giving material.angular.io a refresh from Angular Blog Medium. This is the main configuration file of Nagios core. @sunardo I just ran into this exact same thing. The following settings are done for all MySQL servers. Enjoy unlimited access on 5500+ Hand Picked Quality Video Courses. Usually within a few seconds the full check command pops up and I then kill the while loop and run the check command. 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 wrote a plugin in a bash script to check for current Warnings. Detecting and dealing with state changes is what Nagios is all about. 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). If you don't make use of service dependencies, Nagios won't perform any on-demand service checks. UNKNOWN 2013-04-25 18:11:24 0d 0h 55m 37s 4/4 RESPONSE: UNKNOWN ERROR: /usr/bin/nc does does not exist, i am really getting frustrate from this nagios error, nitin: you need to install the netcat package for your distribution which will provide /usr/bin/nc, I had been using this plugin for a while. These will come through as an Unconfigured Object initially because Nagios XI has never received a Passive check result for this host/service. The documentation uses the example of: for . It can also be used by third-party applications running on different machines to send passive check results to a central Nagios server. Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. For Nagios, many, many Oracle plugins are available for checking database availability and performance. Note: Passive host checks are normally treated as HARD states, unless the passive_host_checks_are_soft option is enabled. Once again, we are dealing with open source software, and Nagios purpose is aimed at monitoring computer systems. Also, depending on your configuration you should add this last file to the main file (/usr/local/nagios/etc/nagios.cfg): Check the configuration and, if no errors or warnings, reload the service: And now you have a new custom check on a host: Nagios has a huge library of plugins available at Nagios Exchange. Add the file to the standard Nagios Core location, /usr/local/nagios/libexec. Here is an example set of passive checks that . System Monitoring Via Nagios and SNMP< SNMP snmp is an internet protocol that allows you to retrieve management information from a remote device or to set configuration settings on a remote device. Here is my configuration : For example sudo gedit /usr/local/nagios/etc/servers/ubuntu_host.cfg # Ubuntu Host configuration file . 03-16-2010, 10:31 AM . There are also different types of checks including external applications or devices that want to report information directly to Nagios. 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). 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. Is there a more efficient way to do this? Difficulties with estimation of epsilon-delta limit proof, The difference between the phonemes /p/ and /b/ in Japanese. Submitting Passive Check Results From Remote Hosts. Plugin then gets executed on the remote machine where is collects the required information and sends then back to Nagios daemon. Nagios also supports a way to monitor hosts and services passively instead of actively. Active checks reach out from the Nagios host and test if a service is doing what it's expected to do. There are several different use cases covered in this KB article: The sections below provide examples of how to perform these checks using different methods. It shows what is performed by Nagios in both cases and what needs to be done by the check command or an external application for passive checks. I've provided some comments here, but things may not be so # clear without further explanation. sudo usermod -aG docker kifarunix. Check whether a document is older than x seconds. It allows to configure alerts and has different states for them. 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. 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, The following figure shows soft states and hard states. Method 3. The check_init_service plugin does not support checking multiple services. This allows for seamless integration of status information from external applications with Nagios. More information on the flap detection logic can be found here. In both the cases, the idea is that Nagios receives information about host statuses over the external commands 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). 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 You have entered an incorrect email address! 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. # Plugin commands (service and host check commands) # Arguments are likely to change between different . The command to submit passive checks is PROCESS_HOST_CHECK_RESULT (visit http://www.nagios.org/developerinfo/externalcommands/commandinfo.php?command_id=115). The plugins can be in any language, Nagios only cares They can be the following: 0: OK 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. 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. This way, the other applications on your Nagios server can report the status of the hosts. Service or Daemon checks are system processes that run in the background, usually configured to start when the system boots. Let us see an example to perform checks on host . Examples: CPU load, RAID status An snmp system is generally considered to have 3 components: Agents Agents expose management information on a device. In this example we are going to define a service and assign it to localhost, because this check is on Nagios itself. NSClient++ includes a service module that can check if a service is running. 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. # 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) . In such cases, Nagios decides when a check is to be performed, runs the check and stores the result. We make use of First and third party cookies to improve our user experience. Repeat this procedure for each Ceph plug-in applicable to the node. Nagios understands the following exit codes: Up To: Contents Now in your configuration for checks for a host you can create the following service check. The above definitions add a host called ubuntu_host and defines the services which will run on this host. 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. Nagios can tell what the status of the service is by reading the exit code of the check. Thanks for contributing an answer to Server Fault! Nonetheless, they can be tuned to match the requirements. The main Nagios process then handles the check results and takes appropriate action (running event handlers, sending notifications, etc.). Monitor whether the apache server is available. 5 check_http examples 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. In other cases, passive checks are the way to go. Having managed large Nagios installations for many years, assigning services to hostgroups is an anti pattern and can make things complicated fast if your environment gets big. 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. Nagios can monitor different mail server components like SMTP, POP, IMAP and mailq. Indicate content type in header for POST request, Regular expression can span to new line (Use this with -r or -R option), Use this regular expression to search for string in the HTTP page, If the site user basic authentication send uid, pwd in the format uid:pwd. 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. These checks help ensure that the dependency logic is as accurate as possible. NPCA includes a service module that can check if a service is running. I don't know if it's best practice or not , but i would declare count Warnings as an integer variable when doing arithmetic operations. This can cause problems if you are submitting passive checks from a remote host or you have a distributed monitoring setup where the parent/child host relationships are different. Minimum number of days a SSL certiface must be valid. Nagios can detect when services start flapping, and can suppress notifications until flapping stops and the service's state stabilizes. 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 same queue that is used for storing results from active checks is also used to store the results from passive checks. An example shell script of how to submit passive service check results to Nagios can be found in the documentation on volatile services. Nagios' check_ssh (of course) keeps marking the process as critical since it can't connect on that port. Making statements based on opinion; back them up with references or personal experience. Based on whether the read was successful or not, the appropriate status code, along with plugin output, is sent out. For example: nagios@nagiosserver:~/ > $ ssh-keygen -t dsa Generating public/private dsa key pair. To monitor hosts and services running on remote machines, Nagios executes plugins and tells what information to collect. Always remember, prior to reloading Nagios, check that there are no errors in the configuration. Based on the condition checked, the plugin can make Nagios aware of a malfunctioning service. These checks can provide useful insight on what is going on within the Nagios server. - specific URL support - ssl option - alternative port - fake user agent - proxy as parameter - proxy from environment variable Usage: check_website [OPTIONS] {HOSTNAME} {HOSTNAME} host to check (dns/ip) [OPTIONS]: Securely download your document with other editable templates, any time, with PDFfiller. See Also: Active Checks, Host Checks, Check Scheduling, Predictive Dependency Checks. 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. hello.. great! How to use it? Can I tell police to wait and call a lawyer when served with a search warrant? It's pretty simple. 1. Unlike active checks, Nagios will not take network topology into consideration by default. In order to be able to submit passive check results, we need to configure Nagios to allow the sending of passive check results, and set the host objects to accept them. 5 check_http Command Examples 1. Here is how it can be done. Test Server 1: custom application (TCP Port. 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_description check http://MYIP/test.php 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. The output indicates that it expires in 300 days. Nagios's primary mode of "service checking" is called an active check. This is very important in situations where a host behind a router is reported to be down because the router is actually down. thanks! I test the command from command line successfull, but when I insert in configuration file (cfg) it gives Error: Service check command check_http -H MYIP -u http://MYIP/test.php specified in service HTTP for host Server01 not defined anywhere!