nagios service check example

Services are those which are used by Nagios to check something about a host. Enable and restart the nrpe service: [user@mon]# systemctl enable nrpe [user@mon]# systemctl restart nrpe. Examen Nagios - Volume: 94 Questions + 7Labs Question: 1 Escalations check_http plugin is used to verify the status of HTTP server (or HTTPS) that is running on a remote host. 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. The __HOST__ is a special service name, which represents the host check in Nagios. Perform these steps to monitor Windows Server with Nagios Core use generic-service ; Name of service template to use Unlike with active host checks, Nagios does not (by default) attempt to determine whether or host is DOWN or UNREACHABLE with passive checks. Using Python Automation to interact with network devices [Tutorial], OpenCV: Detecting Edges, Lines, and Shapes. Nagios Core and Nagios XI has a features to monitoring website URL status. Services that are checked can be in one of four different states: Service checks are performed by plugins, which can return a state of OK, WARNING, UNKNOWN, or CRITICAL. It allows to configure alerts and has different states for them. nagios-check-website - Nagios Exchange The output indicates that it expires in 300 days. The next time Nagios reads the external command file it will place the results of all passive checks into a queue for later processing. Configuring a Nagios Monitoring System | Scaleway Documentation 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. It is possible to configure Nagios so that it will receive status information sent over a command pipe. busy-beaver.mit.edu On the client host that you want to use to connect to remote Docker daemon, generate SSH keys from your user account; ssh-keygen. Method 2. Check HTTP Check whether Apache HTTP is running on a remote server using check_http. How to Define Nagios Timeperiod Exclude for Maintenance Window 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. Let us see an example to perform checks on host . After installing nagios and nagios-plugins-all (via yum), I've c. How can I manually run a nagios check from the command line? (1)Nagios. Nagios Plugins does not include a service plugin however the linux-nrpe-agent does provide check_init_service. Try to put full path in the command line. debug_level=2048 With nagios in debug mode I simply tail the debug_log file debug_file=/var/log/nagios3/nagios.debug. Do roots of these polynomials approach the negative of the Euler-Mascheroni constant? 5 Nagios check_http Plugin Examples for HTTP / HTTPS . b-b.mit.edu The module defines a "good" service as one that is running and a "bad" service is one that is not running, so you can define critical is when more than 0 "good" services exist. Monitoring Windows hosts with NSClient++: Service and system checks By using this website, you agree with our Cookies Policy. Nagios can tell what the status of the service is by reading the exit code of the check. Vulnerability Summary for the Week of June 17, 2019 | CISA Let us assume that the following custom application is also running in the network, listening on a particular port. A good example of such a test is checking whether there are bad blocks on a disk. In order to allow remote hosts to send passive check results to the monitoring host, I've developed the NSCA addon. It essentially does the same thing as a debug level of 2048, but can be used on a per-plugin basis. Difficulties with estimation of epsilon-delta limit proof, The difference between the phonemes /p/ and /b/ in Japanese. I wrote a plugin in a bash script to check for current Warnings. The NRDP addon allows administrators to migrate from using NSCA to NRDP fairly easily. Connect and share knowledge within a single location that is structured and easy to search. In an earlier post, I showed how to . Last updated on September 22, 2020 by Sarmed Rahman. /usr/local/nagios/libexec/check_ping -H 192.168.1.2 -w 100.0,90% -c 200.0,60% .use: . 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. Testing the Commands from Nagios XI Server Now we will test from the Nagios XI server that the command you just added to the NRPE client on the Linux server is working. 28. Service checks in LibreNMS (http, all other Nagios plugins) Start the Nagios again. Nagios understands the following exit codes: A program can be written in any language to work as a Nagios check plugin. Sometimes I find it tricky figuring out exactly what a plugin is doing. It is vital to make sure only legitimate networks have access to the 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. See Also: Active Checks, Service Checks, Host Checks. 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. /usr/nagios/libexec/check_http .. When it is an active check result, Nagios takes the fact that switch1 is down into account and maps the child nodes result into an UNREACHABLE state. nagios-plugins/check_service.sh at master - GitHub 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. So I decided to use the second method. 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. In Nagios, 2 types of checks are performed on hosts and services . Filters such as firewall and TCP wrappers should be used. The check_init_service plugin does not support checking multiple services. 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. You can check whether a SSL certificate of the website expires within the next X number of days as shown below. # SAMPLE HOST CHECK . 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. So in this blog post is all about how I used Hiera to manage the Dev,Test, Prod Stratos environments. Configure Docker Daemon for Remote Connections - kifarunix.com Nagios, NagiosXI, Nagios Core, Nagios Logger, Manage Engine, Idera, Quest, Thousand Eyes Idera Suite and Quest, SQL Monitoring Solution Implementation Here is an example set of passive checks that . 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. An external application checks the status on hosts/services and writes the result to External Command File. NPCA includes a service module that can check if a service is running. Checking NRPE Status In Linux: A Guide To Troubleshooting Issues With Always remember, prior to reloading Nagios, check that there are no errors in the configuration. Note: A service must be defined in Nagios before you can submit passive check results for it! To subscribe to this RSS feed, copy and paste this URL into your RSS reader. I take a slightly more brute-force direction than @Zoredache, I login to the nagios server and do "while true; do ps awwlx | grep NAGIOS_CHECK_NAME; done", while I force a re-check of the service, where NAGIOS_CHECK_NAME is either part of the check name or the IP of the server I am looking for. As with submitting host check results, it is worth mentioning that Nagios will take some time to process passive check results as they are polled periodically from the external commands pipe. Nagios Turn Off All Notifications | 6 Methods Revealed # Sample object config file for Nagios : 3 # 4 # Read the documentation for more information on this configuration file. 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. Far better then Nagios documentation. How to Write a Custom Nagios Check Plugin, /usr/local/nagios/etc/objects/commands.cfg, /usr/local/nagios/etc/objects/localhost.cfg, /usr/lib/nagios/plugins/check_users -w 5 -c 10, /usr/local/nagios/etc/objects/nrpeclient.cfg, Generic installation on Debian-based Client, Set the NRPE Check on the Server Configuration Files, Develop Network Applications for ESP8266 using Mongoose in Linux, How to Setup IKEv2 IPSec VPN Using strongSwan and Let's Encrypt on Rocky Linux 9, ISPConfig Perfect Multiserver setup on Ubuntu 20.04 and Debian 10, Generating Web Site Statistics With AWStats & JAWStats On Debian Lenny, How to Install Jitsi Video Conference Platform on Debian 11, How to Install LAMP Server Stack on Ubuntu 22.04, How to use grep to search for strings in files on the Linux shell, You have Nagios installed and running (You can follow this. Architect and design WAP data flow using BigData Platform. The following diagram shows how both active and passive checks are performed by Nagios. . Are there tables of wastage rates for different fruit and veg? The following figure shows soft states and hard states. Host is just like a computer; it can be a physical device or virtual. Learn more. 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. External applications can submit passive host check results to Nagios by writing a PROCESS_HOST_CHECK_RESULT external command to the external command file. In this tutorial, we'll install Nagios on an Ubuntu 19.10 server, but these steps should work on any Debian-based distro. -c 7 -w 5 -v. Any pointer if I am missing anything but obvious. Even if its parent host is currently DOWN, the child host state is also stored as DOWN. This setting will expose MySQL to all available interfaces, including WAN. 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 Thank you for any assistance you can provide. To figure this out I set nagios into debug mode with the configuration like this. You can create a host file inside the server directory of Nagios and mention the host and service definitions. Active checks are initiated by Nagios process and then run on a regular scheduled basis. 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. 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. It can be used to send results from one Nagios instance to another. 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! For those unfamiliar with Nagios, it is a monitoring system which can execute checks. The results are passed to Nagios in the same way as they are passed for hosts. All of the scripts are located at /etc/nagios-plugins/config/ with the executable files stored at /usr/lib/nagios/plugins/. 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 can tell Nagios to translate DOWN/UNREACHABLE passive check result states to their "proper" state by using the translate_passive_host_checks variable. The following screenshot shows a complete overview of all the service checks that have been configured so far. In general, if a check can be done quickly and does not require long running processes, it should definitely be done as an active service. Save my name, email, and website in this browser for the next time I comment. For example, a plugin which returns a WARNING state will cause a service to have a WARNING state. How to Monitor PostgreSQL using Nagios | Severalnines The Nagios passive check technique described in this article uses Nagios Service Check Acceptor (NSCA) . 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. The same queue that is used for storing results from active checks is also used to store the results from passive checks. However, applications on remote hosts can't do this so easily. rev2023.3.3.43278. Check whether Apache HTTP is running on a remote server using check_http. How can I manually run a nagios check from the command line? Also, MySQL would not let just any host to connect to it. Often, you have situations where other applications can report if a certain service is working properly or not. How can we prove that the supernatural or paranormal doesn't exist? When a host is reported to be DOWN as a passive check result, Nagios does not perform a translation from DOWN to UNREACHABLE. check_command check_http -H MYIP -u http://MYIP/test.php Nagios vs Zabbix - What's the Difference ? (Pros and Cons) checkcommands.cfg in branches/locker-dev/noc/nagios - scripts.mit.edu There are many more services in Nagios which can be used to monitor pretty much anything on the running host. The following file can be modified to do the job. 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. Here is how it can be done. The next parameter specifies the number of seconds after which Nagios should consider the results to be out of date. This file location depends on the configuration you've done, in my case it is in /usr/local/nagios/etc/objects/commands.cfg. Force a check and you will see exactly how the command is being run. The provided scripts contain help on the syntax. Or you can create a custom variable to store the port number , with your example: This article assumes you have a working knowledge of Nagios. i.e: # 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) . How to monitor common services with Nagios - Xmodulo 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. A major difference between hosts and services is that service checks differentiate between soft and hard states. Default is HTTP/1. They have a lot of advantages and some disadvantages. Passive service checks are often used to report the results of long lasting tests asynchronously. The processing of active and passive check results is essentially identical. In such cases, Nagios decides when a check is to be performed, runs the check and stores the result. When you restart the Nagios, this host will start getting monitored by Nagios and the specified services will run. The files and information on this site are the property of their respective owner(s). Is it possible to check a web page through an authenticated proxy server? A good example would be a server that is a part of an application, processing job queues using a database. 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. 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). NRDP Overview - force.com For HTTPS running on a different port, do the following. To learn more, see our tips on writing great answers. 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. 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. Another example is where an application already processes information such as network bandwidth utilization. Depending on the status received on hosts and services, appropriate action is taken. It looks like that with the default install, theres no configuration set up to tell Icinga where to look for the check_http executable. Viewed 12725 times since Tue, Nov 14, 2017, Viewed 18667 times since Tue, Nov 28, 2017, Viewed 70502 times since Thu, Nov 9, 2017, Viewed 9709 times since Tue, Nov 14, 2017, Viewed 12197 times since Wed, Nov 29, 2017, Viewed 47389 times since Thu, Nov 9, 2017, Viewed 14647 times since Sun, Nov 26, 2017, Viewed 42173 times since Mon, Nov 13, 2017, Viewed 18034 times since Wed, Nov 15, 2017, Viewed 22586 times since Sun, Nov 26, 2017. 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. For example, when a web application cannot connect to the database, it will let Nagios know about it immediately. 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! What can a lawyer do if the client wants him to be acquitted of everything despite serious evidence? check_http -H hostname (or) -I ip-address {optional options}. 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. Nagios can monitor different mail server components like SMTP, POP, IMAP and mailq. More information on dependencies can be found here. Method 3. 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 Each server runs one or more common services. Service - Started Check to see if a service is started. Checking if a service is running using SNMP is not very straight forward, checking a process is the best solution here, please refer to the Process Checks KB article. Nagios is a host and service monitor designed to inform you of network problems before your clients, end-users or managers do. Nagios - Checks and States - tutorialspoint.com $ vi /usr/local/nagios/etc/servers/devserver.cfg Note: A host must be defined in Nagios before you can submit passive check results for it! That is superb artile I was looking for! will hold the return value of commands between $( ). So the Nagios Core version is 3.5.1. On any device & OS. You have entered an incorrect email address! The plugins can be in any language, Nagios only cares They can be the following: 0: OK 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. Monitoring Website URL Status Using Nagios check_http - ARKIT This yields less output to dig through. 2. Browse other questions tagged, Start here for a quick overview of the site, Detailed answers to any questions you might have, Discuss the workings and policies of this site. VS Code extension | 35 comentarios en LinkedIn By default Nagios supports URL monitoring and there is an command check_http, however if you want to monitor URL like SSL certification you can also do by extending the command options. 03-16-2010, 10:31 AM . Enjoy unlimited access on 5500+ Hand Picked Quality Video Courses. /usr/lib/nagios/plugins/check_nrpe -H 3.6.123.156 -c check_root_home_du. 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. 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. If up-to-date information has been provided by a passive check during this period, then it will not perform active checks. Does ZnSO4 + H2 at high pressure reverses to Zn + H2SO4? When services change state too frequently they are considered to be "flapping". Plugin then gets executed on the remote machine where is collects the required information and sends then back to Nagios daemon. 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. Even the location of the plugins directory is in there. It allows the implementation of plugins, developed by the community, or even allows us to configure our own monitoring scripts. This is because, very often, passive checks are used to report host and service statuses from other Nagios instances. This increases the security of the database. For example . To turn on everything you want to set debug_level=4095. 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. So I will add at the end of the file the following block:Advertisement.banner-1{text-align:center;padding-top:20px!important;padding-bottom:20px!important;padding-left:0!important;padding-right:0!important;background-color:#eee!important;outline:1px solid #dfdfdf;min-height:335px!important}if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[300,250],'howtoforge_com-banner-1','ezslot_4',111,'0','0'])};__ez_fad_position('div-gpt-ad-howtoforge_com-banner-1-0');.banner-1{text-align:center;padding-top:20px!important;padding-bottom:20px!important;padding-left:0!important;padding-right:0!important;background-color:#eee!important;outline:1px solid #dfdfdf;min-height:335px!important}if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[300,250],'howtoforge_com-banner-1','ezslot_5',111,'0','1'])};__ez_fad_position('div-gpt-ad-howtoforge_com-banner-1-0_1');.banner-1-multi-111{border:none!important;display:block!important;float:none!important;line-height:0;margin-bottom:7px!important;margin-left:auto!important;margin-right:auto!important;margin-top:7px!important;max-width:100%!important;min-height:250px;padding:0;text-align:center!important}. Nagios comes with a wide range of built-in scripts for monitoring services. Follow Up: struct sockaddr storage initialization by network format-string, Identify those arcade games from a 1983 Brazilian music video. The host or the services will be tested again and again till the time the status is permanent. These plugin states directly translate to service states. This can be done to gather all critical errors to a single, central place. 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.