How to install and configure Nagios on Linux. Nagios is one of the most powerful network monitoring systems, which is widely used in the industry. It can actively monitor any network, and generate audioemail warnings and alerts when any problem is detected. The check types and alert timers are fully customizable. Another incredible capability of Nagios is that it can monitor both hosts and services e. IP addresses and TCPUDP port numbers. To explain a little, let us assume that there is a web server that we want to monitor. How To Install Zimbra Mail Server On Centos Linux 32bitIn this article, we will cover how to install and configure Alfresco Community Edition on Linux systems with Nginx as a frontend web server for the application. Step by step guide to install Zimbra Mail Server ZCS 8. CentOS 7 latest version. The mail server setting can be done during Nagios installation. It can also be configured later when needed. Note A valid SMTP configuration is needed for Nagios to. The site for people who want to establish the Network Server with CentOS, Ubuntu, Fedora, Debian. TqAdt2l1aDc/0.jpg' alt='How To Install Zimbra Mail Server On Centos Linux' title='How To Install Zimbra Mail Server On Centos Linux' />Nagios can check whether the server is online by running ping on the IPname of the server as well as it can be set up to provide warnings in case the round trip time RTT to the server increases. Further, Nagios can also check whether TCP port 8. ApacheIIS is not responding. There are also 3rd party monitoring tools that are based on Nagios, such as Centreon, FAN, op. Monitor, which supplement standalone Nagios engine in terms of interface, automation, and technical support. This tutorial explains how to install and configure Nagios on Linux. Install Nagios on Debian or Ubuntu. On a Debian based system, the installation in itself is a very simple process thanks to apt get. The mail server setting can be done during Nagios installation. It can also be configured later when needed. Note A valid SMTP configuration is needed for Nagios to be able send email notifications. As it can be seen, Nagios supports multiple options for email delivery. The most common options would be Internet Site where the server sends email directly to the recipient. Another widely used option is using smarthost or relay server, in which the server sends the email to an intermediary mail server which in turn is responsible for delivering the mail to the recipient. Next, the domain name of the server has to be included in the next step. Finally, the password for the Nagios admin user nagiosadmin is set. This value can also be changed later. Install Nagios on Cent. OS or RHELyum is used for installation. Linux FAQ resource and tutorials. This blog features Linux FAQs, handson tips and detailed tutorials on Linux software, Linux networking, security, virtualization. CentOs.jpeg' alt='How To Install Zimbra Mail Server On Centos Linux' title='How To Install Zimbra Mail Server On Centos Linux' />After setting up the repoforge repository, run yum as follows. Requirements for Monitoring. How To Install Zimbra Mail Server On Centos Linux Operating' title='How To Install Zimbra Mail Server On Centos Linux Operating' />In this tutorial, we want to monitor the following. All Linux server will be checked every 3 minutes. Multiple Serial Ports Python Programming. All Cisco Routers will be checked every 3 minutes. All email alerts should go to the address sentinelexample. Nagios will verify 3 times before sending out any alerts just to be sure that the problem is real. If the RTT to any device exceeds 1. The rest of the tutorial will guide you to configure Nagios on Linux. Nagios Configuration on Ubuntu. ZWpNtAQbIY0/WL7ER6CG9MI/AAAAAAAAAb8/kNSkeEOxZ_84e87-zMWs4-VwQJASirZ2ACLcB/s1600/How%2Bto%2Binstall%2Bowncloud%2B9%2Bcentos%2B7.png' alt='How To Install Zimbra Mail Server On Centos Linux Server' title='How To Install Zimbra Mail Server On Centos Linux Server' />How To Install Zimbra Mail Server On Centos Linux IsoIt is important to know where Nagios configuration files are located. The following table shows the location of Nagios configuration files on Debian based systems. Customizable scripts used for monitoringetcnagios. Configuration files to add hosts, services, define checks and timersusrlibnagiosplugins. Executable files used for monitoring. The following steps are inter related. Hosts, groups for hosts and adding services to host groups are defined. Adding Host Template. The templates defining what to do with a type host is defined. We use the files provided with the installation as sample. First, define a host template for Linux devices. Edit linux server. The parts with bold font are modified. Next, define a host template for Cisco devices. Modify cisco device. The bold font parts are modified. The highlighted parts are modified. Adding Host. Now that the host template is defined, the actual host to be monitored is added. Again, the files provided by default are used as sample. Name of host template to use. The hostname to be used by nagios. The IP address of the host. Name of host template to use. The hostname to be used by nagios. The IP address of the host. Host Group Definition. For ease of management when there are multiple hosts, it is advisable that hosts of similar types are grouped together. Linux Servers. membersour server comma separated list of members. Cisco Devices. membersour server comma separated list of members. Service Definition. First, the command example host check is defined with warning value of 1. Critical values are 5. One IPv. 4 ping request is transmitted. H HOSTADDRESS w 1. Then, the command is associated with host groups. Linux Servers. checkcommand example host check. Cisco Devices. checkcommand example host check. Contact Definition. The required address for sending email added to Nagios. Root. servicenotificationperiod 2. Finally, a dry run is initiated to check whether there are any configuration errors. If there are no errors, Nagios can be restarted safely. Nagios Configuration on Cent. OSRHELThe following shows the locations of Nagios configuration files on Redhat based systems. Configuration files to add hosts, services, define checks and timersusrlibnagiosplugins. Executable files used for monitoring. Adding Host Template. A template is created to define what needs to be done for a specific type of host. The files provided with the installation is modified. Adding Hosts and Host Groups. The configuration file provided with by default is used as a sample. The hosts and host groups are added in the same file. Adding Linux server. Adding Cisco Router. HOST GROUP DEFINITION. Linux Servers. members our server. Service Definition. A service called example host check is defined with warning values of 1. The critical values are 5. Only one IPv. 4 ping request will be transmitted. USER1checkping H HOSTADDRESS w 1. Contact Definition. The email address where alerts will be sent is added into Nagios. Nagios Admin. emailnagioslocalhost, sentinelexample. Finally, we are ready to start the Nagios service. A dry run is recommended to find out errors in configuration. Access Nagios after Configuration. Now you are ready to use Nagios. Nagios can be accessed by opening the URL http IPnagios. The Drums M4a. UbuntuDebian or http IPnagios in case of Cent. OSRHEL e. g. http 1. The user nagiosadmin needs to be authenticated to access the page. Troubleshooting Nagios. When Nagios is not running the way it is supposed to, the first thing to do would be to initiate a dry run. On Debian or Ubuntu. On Cent. OS or RHEL. The log file may also shed some important clue. The path to the log file is located at varlognagiosnagios. How to Install Lets Encrypt SSL Certificate to Secure Apache on RHELCent. OS 76. Extending the last Lets Encrypt tutorial regarding SSLTLS free certificates, in this article we are going to demonstrate how to obtain and install free SSLTLS certificates issued by Lets Encrypt Certificate Authority for Apache web server on Cent. OSRHEL 76 and Fedora distributions too. If youre looking to install Lets Encrypt for Apache on Debian and Ubuntu, follow this guide below Setup Lets Encrypt to Secure Apache on Debian and Ubuntu. Testing Sample Environment. Install Lets Encrypt for Apache on Cent. OS and RHELRequirements. A registered domain name with valid A records to point back to your server public IP Address. Apache server installed with SSL module enabled and Virtual Hosting enabled in case youre hosting multiple domains or subdomains. Step 1 Install Apache Web Server. If not already installed, httpd daemon can be installed by issuing the below command yum install httpd. In order for Lets encrypt software to work with Apache, assure that the SSLTLS module is installed by issuing the command below yum y install modssl. Finally, start Apache server with the following command systemctl start httpd. On RHELCent. OS 7. On RHELCent. OS 6. Step 2 Install Lets Encrypt SSL Certificate. The simplest method of installing Lets Encrypt client is by cloning github repository in your filesystem. To install git on your system you must enable Epel repositories with the following command. Once Epel repos are added in your system, go ahead and install git client by running the command below yum install git. Now, once you have installed all the required dependencies in order to deal with Lets Encrypt, go to usrlocal directory and start pulling the Lets Encrypt client form its official github repository with the following command cd usrlocal. Step 3 Obtain a Free Lets Encrypt SSL Certificate for Apache. The process of obtaining a free Lets Encrypt Certificate for Apache is automated for Cent. OSRHEL thanks to the apache plugin. Lets run Lets Encrypt script command in order to obtain a SSL Certificate. Go to Lets Encrypt installation directory from usrlocalletsencrypt and run the letsencrypt auto command by providing apache option and the d flag for every subdomain you need a certificate. Create Lets Encrypt SSL Certificate for Apache. Supply the email address that will be used by Lets Encrypt to recover your lost key or for urgent notices and press Enter to continue. Add Email Address for Lets Encrypt. Agree the terms of the license by hitting Enter key. Agree Lets Encrypt License. On Cent. OSRHEL, by default, Apache server does not use the concept of separating directories for enabled hosts from available inactive hosts as Debian based distribution do. Also, virtual hosting is disabled by default. The Apache statement which specifies the name of the server Server. Name its not present on SSL configuration file. To activate this directive, Lets Encrypt will prompt you to select a virtual host. Because it does not find any Vhost available, select the ssl. Lets Encrypt client and press Enter to continue. Active Virtual. Host Directive and Select ModSSL1. Next, choose the Easy method for HTTP requests and press Enter to move forward. Allow Easy HTTP Requests. Finally, if everything went smooth, a congratulation message should be displayed on the screen. Press Enter to release the prompt. Lets Encrypt Enabled on Domain. Thats it You have successfully issued a SSLTLS certificate for your domain. Now you can start browsing your website using HTTPS protocol. Step 4 Test Free Lets Encrypt Encryption on Domain. In order to test the straightness of your domain SSLTLS handshake visit the below link and test your certificate on your domain. Verify Lets Encrypt Certificate on Domain. If you receive a series of reports concerning your domain vulnerability in the conducted tests, then you need to fix those security holes urgently. An overall rating of C class makes your domain very insecure. To fix these security problems, open Apache SSL configuration file and make the following changes vi etchttpdconf. Search for line with SSLProtocol statement and add SSLv. Fix Apache SSL Configuration. Go deeper in the file, search and comment the line with SSLCipher. Suite by placing a in front of it and add the following content under this line SSLCipher. Suite ECDHE RSA AES1. GCM SHA2. 56 ECDHE ECDSA AES1. GCM SHA2. 56 ECDHE RSA AES2. GCM SHA3. 84 ECDHE ECDSA AES2. GCM SHA3. 84 DHE RSA AES1. GCM SHA2. 56 DHE DSS AES1. GCM SHA2. 56 k. EDHAESGCM ECDHE RSA AES1. SHA2. 56 ECDHE ECDSA AES1. SHA2. 56 ECDHE RSA AES1. SHA ECDHE ECDSA AES1. SHA ECDHE RSA AES2. SHA3. 84 ECDHE ECDSA AES2. SHA3. 84 ECDHE RSA AES2. SHA ECDHE ECDSA AES2. SHA DHE RSA AES1. SHA2. 56 DHE RSA AES1. SHA DHE DSS AES1. SHA2. 56 DHE RSA AES2. SHA2. 56 DHE DSS AES2. SHA DHE RSA AES2. SHA AES1. 28 GCM SHA2. AES2. 56 GCM SHA3. AES1. 28 SHA2. 56 AES2. SHA2. 56 AES1. 28 SHA AES2. SHA AES CAMELLIA DES CBC3 SHA NULL e. NULL EXPORT DES RC4 MD5 PSK a. ECDH EDH DSS DES CBC3 SHA EDH RSA DES CBC3 SHA KRB5 DES CBC3 SHA. SSLHonor. Cipher. Order on. SSLOptions Strict. Require. Configure SSL Configuration. After youve made all the above changes, save and close the file, then restart Apache daemon to apply changes. On RHELCent. OS 7. On RHELCent. OS 6. Now, tests the status of your domain encryption again, by visiting the same link as above. To perform retests hit the Clear cache link from the website. Test Lets Encrypt SSL Certificate on Website. Now you should get a class A overall rating, which means your domain is highly secured. Step 4 Auto Renew Lets Encrypt Certificates on Apache. This beta version of Lets Encrypt software releases certificates with expiration date after 9. So, in order to renew the SSL certificate, you must execute the letsencrypt auto command again before expiration date, with the same options and flags used to obtain the initial certificate. An example on how to manually renew the certificate is presented below. To automate this process, create the following bash script provided by github erikaheidi, in usrlocalbin directory with the following content. Add the following content to le renew centos file binbash. ERROR The config file for the certificate certdomain was not found. ERROR you must provide the domain name for the certificate renewal. ERROR certificate file not found for domain domain. Not Aftercut c 2. Checking expiration date for domain. The certificate is up to date, no need for renewal daysexp days left. The certificate for domain is about to expire soon. Starting renewal request. Restarting Apache. Renewal process finished for domain domain. Grant execution permissions for the script, install bc package and run the script in order to test it. Use your domain name as a positional parameter for the script. Issue the below commands to accomplish this step yum install bc. Finally, using Linux scheduling, add a new cron job in order to run the script every two months, assuring that your certificate will be updated before expiration date. Add the following line at the bottom of the file. Thats it Your Apache server running on top of Cent. Able2extract 7.0 Crack.