The object needs to have the passive_checks_enabled option set to 1 for Nagios to accept passive check results over the command pipe. . notifications_enabled 0 Service status codes are the same as those for active checks0 for OK, 1 for WARNING, 2 for CRITICAL, and 3 for an UNKNOWN state. Passive service checks are often used to report the results of long lasting tests asynchronously. When services change state too frequently they are considered to be "flapping". Nagios executes event handlers to handle hard states. This defines that check_nrpe is the command and check_root_home_du is the value of $ARG1$. 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. It allows the implementation of plugins, developed by the community, or even allows us to configure our own monitoring scripts. # Defaults to 0, put to 1 for systemd. Check WMI Plus includes a service module that can check if a service is running. Nagios Enterprises makes no claims or warranties as to the fitness of any file or information on this website, for any purpose whatsoever. 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. 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. It also defines Nagios user and group under which Nagios instance is running. 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. Learn more about Stack Overflow the company, and our products. NSClient++ includes a service module that can check if a service is running. Agree 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. check_command /usr/share/nagios/plugins/check_http -H MYIP -u http://MYIP/test.php, Hi, If you don't make use of service dependencies, Nagios won't perform any on-demand service checks. The plugins can be in any language, Nagios only cares They can be the following: 0: OK 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. Passive checks are also used when configuring distributed or redundant monitoring installations. The host status code should be 0 for an UP state, 1 for DOWN and 2 for an UNREACHABLE state. 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. A command to submit passive checks is PROCESS_SERVICE_CHECK_RESULT (visit http://www.nagios.org/developerinfo/externalcommands/commandinfo.php?command_id=114). No paper. Follow these steps to install the plugin: Download the plugin. . Active checks reach out from the Nagios host and test if a service is doing what it's expected to do. mark separates the command from the arguments in the check_command entry. - 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]: Based on whether the read was successful or not, the appropriate status code, along with plugin output, is sent out. 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 above definitions add a host called ubuntu_host and defines the services which will run on this host. This command accepts the host name, service description, status code, and the textual output from a check. Nagios, NagiosXI, Nagios Core, Nagios Logger, Manage Engine, Idera, Quest, Thousand Eyes Idera Suite and Quest, SQL Monitoring Solution Implementation Nagios server in this example is hosted on 192.168.0.150 and an example client is hosted on IP 192.168.0.200. To allow it to grow bigger before rotating, add more zeroes, for example. On any device & OS. This feature is only available to subscribers. Enable and restart the nrpe service: [user@mon]# systemctl enable nrpe [user@mon]# systemctl restart nrpe. The plugin returns a CRITICAL state if the service is not started. 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 very important in situations where a host behind a router is reported to be down because the router is actually down. You can create a host file inside the server directory of Nagios and mention the host and service definitions. By clicking Post Your Answer, you agree to our terms of service, privacy policy and cookie policy. $ vi /usr/local/nagios/etc/servers/devserver.cfg 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. Check WMI Plus allows you to check multiple services, here is an example that checks for two services that are running. Yeah, it's totally brute-force, but it works for me. will hold the return value of commands between $( ). 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. The service check runs in a child process that was fork()ed from the main Nagios daemon. This usually calls for some effort. Can i specify what a valid response is, i.e. This user is then granted all permission to all databases and will be used for monitoring. (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".) All other servicemarks and trademarks are the property of their respective owner. Up To: Contents Nagios understands the following exit codes: A program can be written in any language to work as a Nagios check plugin. You know the basics on Nagios administration. Here is my configuration : 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. Apply these agent configurations After the NRDP installation, install the NCPA. How can I manually run a nagios check from the command line? It has been designed to run . hello.. The processing of active and passive check results is essentially identical. Nagios check_by_ssh returns status 3 even though running the command manually works? Giving material.angular.io a refresh from Angular Blog Medium. In order to use them, the host needs to be configured to accept passive checks results. Detecting and dealing with state changes is what Nagios is all about. Hello, ask a question, check_http detect page size, page size detection value changes again, the alarm. An external application checks the status of a host or service. How can we prove that the supernatural or paranormal doesn't exist? 5 check_http examples Select check_cluster from the plugin pop-up menu. You need to add the full path to it in the check_command. Service or Daemon checks are system processes that run in the background, usually configured to start when the system boots. 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. Be aware that the service module is cAsE SeNsative, you can overcome this with the match= argument. Check whether Apache HTTP is running on a remote server using check_http. It allows to configure alerts and has different states for them. 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. Services are those which are used by Nagios to check something about a host. Contribute to vishalsingh17/GitiPedia development by creating an account on GitHub. Here is how it can be done. Nagios: Disable notifications from command line on Windows/Linux. 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. # Sample object config file for Nagios : 3 # 4 # Read the documentation for more information on this configuration file. It says Unknown option specified in config file , check_http -I 10.0.0.76 -p 8192 url=/MYServiceBus/ post= eregi=.Status_Code.0./Status_Code. Active checks are most common in the Nagios world. A good example would be a server that is a part of an application, processing job queues using a database. The next time Nagios reads the external command file it will place the results of all passive checks into a queue for later processing. The following line is commented out to make MySQL listens on all interfaces. An external application checks the status on hosts/services and writes the result to External Command File. This is how your host definitions look currently . Note: Certain nodes in the above example have combined check results, such as memory/virtual, memory/swap, and processes. 28. $ 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. No software installation. 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. Examples include server load, number of concurrent processes, number of logged in users via NRPE extension. More information on how this works can be found here. Services are those which are used by Nagios to check something about a host. What you are doing down is sending a Passive check result for the service SNMP Traps - Users for the host CentOS. If you are new to the Nagios network monitoring system, see the resources at the Nagios website. Nagios' check_ssh (of course) keeps marking the process as critical since it can't connect on that port. Test Server 1: custom application (TCP Port. There are many more services in Nagios which can be used to monitor pretty much anything on the running host. In such a case, checks are done by other programs, and their results are sent to Nagios. Note: Passive host checks are normally treated as HARD states, unless the passive_host_checks_are_soft option is enabled. It will give you all the available options: :), I will also menton for new users that using, The debug_levels are binary - 2048 only turns on messages from macros. check_command check_http -H MYIP -u http://MYIP/test.php However, applications on remote hosts can't do this so easily. Default is HTTP/1. In order to allow remote hosts to send passive check results to the monitoring host, I've developed the NSCA addon. Follow Up: struct sockaddr storage initialization by network format-string, Identify those arcade games from a 1983 Brazilian music video. (In this example, the script will print All ok and it will exit with 0, the OK . Save my name, email, and website in this browser for the next time I comment. The plugin returns a CRITICAL state if the service is not started. Nagios also offers another way to work with the statuses of hosts and services. can nagios adjust its check time based on the status info? Use Puppet environments. Some of the scripts provided with Nagios are restricted to the local server only. Allow Nagios server to run commands on the client by adding it to the allowed_hosts entry in /etc/nagios/nrpe.cfg. Please refer tohttp://tldp.org/LDP/abs/html/untyped.html, hi! There are no attachments for this article. I wouldn't leave this setting on normally though, it is very verbose and fills your log file at a rapid rate. 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. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Note that there are possible security implications of this change, so it's worth mentioning a few words: The following tuning should do the trick. By using this website, you agree with our Cookies Policy. It is generally recommended to run the Nagios service check scripts in CLI before adding them to Nagios. 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. 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 has several benefits over NSCA, including: Nagios stores the status of the hosts and services it is monitoring to determine if they are working properly or not. /usr/nagios/libexec/check_http .. Always remember, prior to reloading Nagios, check that there are no errors in the configuration. To do this: Navigate to Configuration > Command > New. These checks can provide useful insight on what is going on within the Nagios server. 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 . What is check_http? Even the location of the plugins directory is in there. Get your subscription here. Far better then Nagios documentation. It is possible to configure Nagios so that it will receive status information sent over a command pipe. debug_level=2048 With nagios in debug mode I simply tail the debug_log file debug_file=/var/log/nagios3/nagios.debug. The check_ncpa.py plugin enables Nagios to monitor the installed NCPAs on the hosts. This task is really easy as Nagios has a built-in command for this. Does ZnSO4 + H2 at high pressure reverses to Zn + H2SO4? This command accepts the host name, status code, and the textual output from a check. Check whether a document is older than x seconds. This tutorial will cover the process of using some of these scripts for checking common services, such as MySQL, Apache web server, DNS, etc. In many cases, the time taken is not enough, as some checks need to be performed over a longer period of time to have satisfactory results. Nagios's primary mode of "service checking" is called an active check. 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. 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. I've provided some comments here, but things may not be so # clear without further explanation. The Nagios server is running on Ubuntu. Establish a terminal session to your Nagios XI server and execute the following command: 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. NSClient++ includes a service module that can check if a service is running. 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. command line output while running with -S is check_http: Invalid option SSL is not available, Next post: UNIX / Linux whatis Command Examples, Previous post: UNIX / Linux split Command Examples, Home | Linux 101 Hacks Table of Contents | Contact | Email | RSS | Copyright 20092022 Ramesh Natarajan All rights reserved | Terms of Service, host name of the server where HTTP (or HTTPS) daemon is running, Port number where HTTP server runs. Thanks for contributing an answer to Server Fault! Active checks can be used to "poll" a device or service for status information every so often. The output indicates that it expires in 300 days. All of the scripts are located at /etc/nagios-plugins/config/ with the executable files stored at /usr/lib/nagios/plugins/. See Also: Active Checks, Service Checks, Host Checks. When a URL is redirected, use this to either follow the URL, or send ok, warning, or critical notification, Specify the minimum and maximum page size expected in bytes. Nagios check service frequency based on service status, how can execute nagios commands from command line in linux. ##### # Sample object config file for Nagios # # Read the documentation for more information on this configuration file. 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 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 can be used to send results from one Nagios instance to another. The figure shown below shows an active check . I am gettinr this error in nagios3. On-demand checks are performed as part of the predictive service dependency check logic. 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. So in the server set the files: /usr/local/nagios/etc/objects/commands.cfg: /usr/local/nagios/etc/objects/nrpeclient.cfg: Note that the ! The provided scripts contain help on the syntax. The NRDP addon allows administrators to migrate from using NSCA to NRDP fairly easily. I've # provided some comments here, but things may not be so clear without further # explanation, so make sure to read the HTML documentation! 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. you have the flexibility of sending the passive check to Nagios with a different hostname. This should enable MySQL to listen on all interfaces, as well as accept incoming connections from user nagios at any host. The figure shown below shows a passive check . this is THE MOST comprehensive and straight forward turorial I've seen. This can be done to gather all critical errors to a single, central place. After defining the command you can associate that command to a service, and then to a host. 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. # These are some example service check commands. Please note that this article is published by Xmodulo.com under a Creative Commons Attribution-ShareAlike 3.0 Unported License. Go to the Nagios interface via a web browser and log in as the nagiosadmin user. All other servicemarks and trademarks are the property of their respective owner. Stats Graphs - Live data graphs of CPU, memory, interface bandwidth, and disk usage. Check HTTPS Check whether Apache HTTPS is running on a remote server using check_http. Add additional tags that should be sent in the HTTP header. These types of checks are called Active Checks. Another difference is that active checks require much less effort to be set up when compared to passive checks. 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. Nagios Plugins does not include a service plugin however the linux-nrpe-agent does provide check_init_service. i.e: This is a plugin for Nagios wich you can use to check if a linux service is running. These types of checks are called Passive Checks. On the client host that you want to use to connect to remote Docker daemon, generate SSH keys from your user account; ssh-keygen.