nagios service check example
Each server runs one or more common services. 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! Note that all the configuration in this section is done on the client to be checked, not in the nagios server. By default you do not need to change any of the lines in this file and . On a finishing note, Nagios can monitor many other sectors of a network. Passive checks are also used when configuring distributed or redundant monitoring installations. Even the location of the plugins directory is in there. 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. These are executed on regular intervals, as defined by check_interval and retry_interval. Start the Nagios again. Examples: CPU load, RAID status An snmp system is generally considered to have 3 components: Agents Agents expose management information on a device. Or you can create a custom variable to store the port number , with your example: It essentially does the same thing as a debug level of 2048, but can be used on a per-plugin basis. Define the checks on /etc/nagios/nrpe_local.cfg. Test Server 1: custom application (TCP Port. The following line is commented out to make MySQL listens on all interfaces. The check_ncpa.py plugin enables Nagios to monitor the installed NCPAs on the hosts. Why is there a voltage on my HDMI and coaxial cables? 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. You'll see the following line inside the /etc/rc.d/init.d/nagios script for the Nagios startup: $NagiosBin -d $NagiosCfgFile 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. The figure shown below shows an active check . It only takes a minute to sign up. When you restart the Nagios, this host will start getting monitored by Nagios and the specified services will run. All other servicemarks and trademarks are the property of their respective owner. 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. 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. The script should then post results to the Nagios daemon. External applications can submit passive host check results to Nagios by writing a PROCESS_HOST_CHECK_RESULT external command to the external command file. The same queue that is used for storing results from active checks is also used to store the results from passive checks. Another example is where an application already processes information such as network bandwidth utilization. How to install and configure Nagios Core. To turn on everything you want to set debug_level=4095. They have a lot of advantages and some disadvantages. We make use of First and third party cookies to improve our user experience. In such a case, checks are done by other programs, and their results are sent to Nagios. You know the basics on Nagios administration. 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. The following file can be modified to do the job. The processing of active and passive check results is essentially identical. 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. The object file localhost.cfg allows for parameters to be passed to check_ssh. Go to the Nagios interface via a web browser and log in as the nagiosadmin user. Consider that you have put your host definitions inside host1.cfg file in /usr/local/nagios/etc/objects directory. 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 can be used to send results from one Nagios instance to another. The default FQDN used for testing is www.google.com, but it can be changed as needed. This way, the other applications on your Nagios server can report the status of the hosts. Cached checks will only provide a performance increase if you are making use of service dependencies. 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. 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). Contribute to vishalsingh17/GitiPedia development by creating an account on GitHub. How to use it? 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. 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. can nagios adjust its check time based on the status info? The following is an example of the required configuration for a host that accepts passive checks and has active checks disabled: Configuring services is exactly the same as with hosts. 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 general, if a check can be done quickly and does not require long running processes, it should definitely be done as an active service. This task is really easy as Nagios has a built-in command for this. . Add the file to the standard Nagios Core location, /usr/local/nagios/libexec. Select check_cluster from the plugin pop-up menu. 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. 5 check_http examples Otherwise we must rely on parsing the # output from the service management tool. 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. Establish a terminal session to your Nagios XI server and execute the following command: I've deployed a new instance of Nagios on a fresh install of CentOS 7 via the EPEL repository. This file location depends on the configuration you've done, in my case it is in /usr/local/nagios/etc/objects/commands.cfg. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Base your decision on 2 verified in-depth peer reviews and ratings, pros & cons, pricing, support and more. However, applications on remote hosts can't do this so easily. 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. I will use a simple example. This tutorial will cover the process of using some of these scripts for checking common services, such as MySQL, Apache web server, DNS, etc. The sections below provide examples of how to perform these checks using different methods. Nagios also offers a tool for sending passive check results for hosts and services over a network. If you preorder a special airline meal (e.g. 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. By using this website, you agree with our Cookies Policy. 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. Nagios executes event handlers to handle hard states. On the next screen: Enter a unique name in the Command Name field (suggest one is check_host_cluster and the other check_service_cluster) Append --host to the Command Line section for host . Now let us add check_interval directive. $ 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. First, the servers are defined in Nagios. It is generally recommended to run the Nagios service check scripts in CLI before adding them to Nagios. The external application writes the results of the check to the. Line 1 ##### 2 # Sample object config file for Nagios : 3 # 4 # Read the documentation for more information on this configuration file. 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. How can I make Status Information for Nagios services easier to read? 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. In Nagios, 2 types of checks are performed on hosts and services . Scheduled service checks are run in parallel. 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. Nagios understands the following exit codes: 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. # 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) . Can i specify what a valid response is, i.e. 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. Affordable solution to train a team and make them project ready. >Mainly Focus on Kafka and Cloudera services, Cluster . Service or Daemon checks are system processes that run in the background, usually configured to start when the system boots. The key features of passive checks are as follows: The major difference between active and passive checks is that active checks are initiated and performed by Nagios, while passive checks are performed by external applications. 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. This should enable MySQL to listen on all interfaces, as well as accept incoming connections from user nagios at any host. 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. I wouldn't leave this setting on normally though, it is very verbose and fills your log file at a rapid rate. For example, a plugin which returns a WARNING state will cause a service to have a WARNING state. This increases the security of the database. Thanks for contributing an answer to Server Fault! hello.. 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 . 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.
