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. Monitoring Website URL Status Check WMI Plus allows you to check multiple services, here is an example that checks for two services that are running. 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. Another example is where an application already processes information such as network bandwidth utilization. This way, the other applications on your Nagios server can report the status of the hosts. 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. 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. A good example would be a server that is a part of an application, processing job queues using a database. The service check runs in a child process that was fork()ed from the main Nagios daemon. Service checks in LibreNMS (http, all other Nagios plugins) We must install this software there to install the "check_nrpe" plugin that we use to perform active checks using the NRPE. 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 is a plugin for Nagios wich you can use to check if a linux service is running. 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 external application checks the status of a host or service. vegan) just to try it, does this inconvenience the caterers and staff? $ vi /usr/local/nagios/etc/servers/devserver.cfg Nagios will be configured to monitor SMTP and mail queue of the server. The time performed is specified in seconds. This example is going to restart the crond service as it is unlikely to cause any issues. (If I were running df -h on the linux CLI, I'm using the "h" flag - in the case of the df command, the h stands for "human readable".) What can a lawyer do if the client wants him to be acquitted of everything despite serious evidence? It can report each problem when accessing the database. 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. A user nagios is created for both localhost and for any host. this is more along the lines of what i meant. It's pretty simple. Establish a terminal session to your Nagios XI server and execute the following command: 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. How to install and configure nagios on centos 7 step by step leri I Have problem with the check_http when I try ur command test , I have the next message : After installing nagios and nagios-plugins-all (via yum), I've c. Nagios will still handle all notifications, event handlers, and dependencies between hosts and services. sudo usermod -aG docker kifarunix. 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. It is generally recommended to run the Nagios service check scripts in CLI before adding them to Nagios. . 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. All other servicemarks and trademarks are the property of their respective owner. First you should define a command in the commands.cfg file. 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. Expected response string. These will come through as an Unconfigured Object initially because Nagios XI has never received a Passive check result for this host/service. In fact, we officially. 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. However, applications on remote hosts can't do this so easily. The flexibility provided by Nagios is perfect for these case scenarios. Active checks reach out from the Nagios host and test if a service is doing what it's expected to do. Check HTTPS Check whether Apache HTTPS is running on a remote server using check_http. Server Fault is a question and answer site for system and network administrators. 1 check_http -p 8083 - user4556274 Jul 29, 2016 at 12:49 Add a comment 3 Answers Sorted by: 3 You can specify the port number directly in the command but you will must create one command per tested port. In addition, it is run on the Linux operating system, precisely for the purpose of monitoring devices that are executed on Windows, Unix and Linux operating systems.Its main task is to constantly check key server resources, applications, networks and tasks. Would you please be so kind as to help me? If the situation involves reporting problems from other applications or machines, it is definitely a use case for a passive check. On-demand as needed for predictive service dependency checks. For example: nagios@nagiosserver:~/ > $ ssh-keygen -t dsa Generating public/private dsa key pair. If you are new to the Nagios network monitoring system, see the resources at the Nagios website. you have the flexibility of sending the passive check to Nagios with a different hostname. 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. Nagios also offers a way of combining the benefits of both active and passive checks. (1 + 2 + + 2048), Also note that your debug file will grow quickly and then rotate itself. 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. Sometimes I find it tricky figuring out exactly what a plugin is doing. Go to the /usr/local/nagios/libexec dir (assuming you have installed nagios from source, if you have used a package from your distribution, check the docs of your package): $ cd /usr/local/nagios/libexec execute the check_dns plugin with the --help switch. Use Hiera. Default is HTTP/1. Stats Graphs - Live data graphs of CPU, memory, interface bandwidth, and disk usage. How to Monitor PostgreSQL using Nagios | Severalnines This feature is only available to subscribers. I am gettinr this error in nagios3. To identify the status of a monitored service, Nagios runs a check plugin on it. The following directive allows it: Setting up hosts or services for passive checking requires an object to be defined and set up so as not to perform active checks. In such cases, Nagios decides when a check is to be performed, runs the check and stores the result. These are real-time graphs showing things like CPU usage, memory usage, and bandwidth. Last updated on September 22, 2020 by Sarmed Rahman. Contribute to vishalsingh17/GitiPedia development by creating an account on GitHub. Does anyone have a working example of a dependencies.cfg file for nagios? In most cases you'll use Nagios to monitor your hosts and services using regularly scheduled active checks. This usually calls for some effort. JOB, 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. More information on how this works can be found here. The following figure shows soft states and hard states. 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. Pass the specified string as User Agent in HTTP header. Nagios check_dns / check_ip Example - Nagios Exchange 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. Ali Sabry en LinkedIn: Code-GPT is an extension for VS Code that November 2012, by Simon Krenger. 1. }. Architect and design WAP data flow using BigData Platform. Nagios stores the status of the hosts and services it is monitoring to determine if they are working properly or not. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. 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. Based on the condition checked, the plugin can make Nagios aware of a malfunctioning service. NSClient++ allows you to check multiple services, here is an example that checks for two services that are running. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. The plugin returns a CRITICAL state if the service is not started. Monitor DNS server with Nagios Here is the output when the RemoteAccess service was started: Checking if a service is stopped using SNMP is not very straight forward, checking a process is the best solution here, please refer to the Process Checks KB article. Nevertheless, in response to your comment, I don't think there's an error in that, as Bash variables are untyped. When services change state too frequently they are considered to be "flapping". Simple invoke the command with -s parameter and the name of the service Example of use ./check_service -s ntpd Thank you! Affordable solution to train a team and make them project ready. The __HOST__ is a special service name, which represents the host check in Nagios. An example shell script of how to submit passive service check results to Nagios can be found in the documentation on volatile services. When a host is reported to be DOWN as a passive check result, Nagios does not perform a translation from DOWN to UNREACHABLE. Filters such as firewall and TCP wrappers should be used. Learn more about Stack Overflow the company, and our products. Remotely monitor servers with the Nagios check_by_ssh plugin 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. 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. Nagios - Hosts and Services - tutorialspoint.com Examples: CPU load, RAID status An snmp system is generally considered to have 3 components: Agents Agents expose management information on a device. 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. 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. 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. Hosts and service configurations are the building blocks of Nagios Core. If you don't make use of service dependencies, Nagios won't perform any on-demand service checks. Nagioshttpdgccgd. [SOLVED] Nagios dependencies.cfg example file great! 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. 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). To monitor hosts and services running on remote machines, Nagios executes plugins and tells what information to collect. This will give an idea on whether the execution will be successful and what the output of the script will look like. More information on the flap detection logic can be found here. check_command check_http -H MYIP -u http://MYIP/test.php 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. Nagios dependencies.cfg example file. A sample definition for a host that runs an active check if there has been no result provided within the last two hours: The following is an illustration showing when Nagios would invoke active checks: Each time there is at least one passive check result that is still valid (i.e., was received within the past two hours), Nagios will not perform any active checks. Passive Checks Documentation NCPA - Nagios The Nagios server is running on Ubuntu. Add additional tags that should be sent in the HTTP header. It has been designed to run . I wrote a plugin in a bash script to check for current Warnings. 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 mechanism includes password protection, along with encryption, to prevent injection of false results in to Nagios. Based on whether the read was successful or not, the appropriate status code, along with plugin output, is sent out. I will leave this script with all the other Nagios plugins inside /usr/local/nagios/libexec/ (This directory may be different depending on your confiugration). 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. 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). I will use a simple example. Current status from nagios Web interface: Thank you article really help a beginer like me ;-). The line should look like: Define the standard checks that you will perform on every client with NRPE. How to handle a hobby that makes income in US. hello.. A major difference between hosts and services is that service checks differentiate between soft and hard states. Method 2. 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. 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. How to configure service templates - GroundWork Support service_description check http://MYIP/test.php This is the main configuration file of Nagios core. Enable and restart the nrpe service: [user@mon]# systemctl enable nrpe [user@mon]# systemctl restart nrpe. 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. In the Select resource macro: section, select USER1. Nagios will ignore all check results for hosts that had not been configured before it was last (re)started. I've # provided some comments here, but things may not be so clear without further # explanation, so make sure to read the HTML documentation! 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 a plugin for Nagios wich you can use to check if a linux service is running. Can I tell police to wait and call a lawyer when served with a search warrant? It is possible to configure Nagios so that it will receive status information sent over a command pipe. Nagios is a host and service monitor designed to inform you of network problems before your clients, end-users or managers do. When defining and testing new services in nagios I have been restarting nagios, then clicking the service, and rescheduling a check for as soon as possible, then waiting until the check happens. 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 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}. Line 1 ##### 2 # Sample object config file for Nagios : 3 # 4 # Read the documentation for more information on this configuration file. This user is then granted all permission to all databases and will be used for monitoring. If you preorder a special airline meal (e.g. nagiosrpm. # Nagios Exit Codes OK=0 WARNING=1 CRITICAL=2 UNKNOWN=3 # Weather or not we can trust the exit code from the service management tool. NSCA stands for Nagios Service Check Acceptor. 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. The object needs to have the passive_checks_enabled option set to 1 for Nagios to accept passive check results over the command pipe. It allows to configure alerts and has different states for them. Attributes can be used for both hosts and services. Linux Check Service - Nagios Exchange Rather, Nagios takes the passive check result to be the actual state the host is in and doesn't try to determine the host's actual state using the reachability logic. It looks like that with the default install, theres no configuration set up to tell Icinga where to look for the check_http executable. 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. The next time Nagios reads the external command file it will place the results of all passive checks into a queue for later processing. In order to use them, the host needs to be configured to accept passive checks results. Note that all the configuration in this section is done on the client to be checked, not in the nagios server. Thus, the difference between active and passive check is that active checks are run by Nagios and passive checks are run by external applications. I just used that simple script as an example, any language can be used to write your own custom plugin. Nagios also offers another way to work with the statuses of hosts and services. The default FQDN used for testing is www.google.com, but it can be changed as needed. After defining the command you can associate that command to a service, and then to a host. Nagios Plugins does not include a service plugin however the linux-nrpe-agent does provide check_init_service. TRUST_EXIT_CODE=0 usage () { cat <<EOF Like every Nagios plugin, you will want to check from the command line before adding it to the configuration files. How to monitor common services with Nagios - Xmodulo