Posts Tagged “rhel”

knife Quick Reference

This is a quick reference for few of the commands which I use often.

Written on August 26, 2016
centos rhel nagios opensource monitoring


Migrating Nagios XI to a New Server on Centos6.6

Migrating an old Nagios backup to a new nagiosxi server. Migration is simple in Nagios XI, you a backup and restore it. Once that is done we need to update/add the clients with IP of the new server, so that both Nagios get alerts. After a while once we are comfortable with the new server we can decommission the old one.

Written on August 18, 2016
centos rhel nagiosxi nagios opensource monitoring


Setup/Configuration Nagios XI on Centos6.6

Nagios monitors your entire IT infrastructure to ensure systems, applications, services, and business processes are functioning properly. In the event of a failure, Nagios can alert technical staff of the problem, allowing them to begin remediation processes before outages affect business processes, end-users, or customers.

Written on August 12, 2016
centos rhel nagios nagiosxi monitoring


RPM Command Cheat Sheet

RPM (Redhat Package Manager) is the most popular package utility and is used mostly on RHEL, Centos and Fedora. RPM helps user/admins to build, install, query, verify, update, and remove/erase individual software packages.

Written on August 11, 2016
centos rhel rpms


YUM Repository Creation on HTTPD Web Server.

Setting up yum repos on RHEL using httpd. We will be setting up httpd and yum repo on top of it. So that we can access yum over http.

Written on November 3, 2015
linux hadoop webserver http httpd yum rhel centos


Access Filter Setup with SSSD

If using access_provider = ldap, this option is mandatory. It specifies an LDAP search filter criteria that must be met for the user to be granted access on this host. If access_provider = ldap and this option is not set, it will result in all users being denied access. Use access_provider = allow to change this default behaviour.

Written on October 23, 2015
linux hadoop sssd access-filter rhel centos security


Redhat Intergration with Active Directory using SSSD.

There are inherent structural differences between how Windows and Linux handle system users. The user schemas used in Active Directory and standard LDAPv3 directory services also differ significantly. When using an Active Directory identity provider with SSSD to manage system users, it is necessary to reconcile Active Directory-style users to the new SSSD users. There are two ways to achieve it:

Written on October 6, 2015
linux hadoop sssd active-directory ad ldap rhel centos security


Simple Steps to Intergrate RHEL with Active Directory using SSSD.

There are inherent structural differences between how Windows and Linux handle system users. The user schemas used in Active Directory and standard LDAPv3 directory services also differ significantly. When using an Active Directory identity provider with SSSD to manage system users, it is necessary to reconcile Active Directory-style users to the new SSSD users. There are two ways to achieve it:

Written on October 6, 2015
linux hadoop sssd ad active-directory rhel centos security


Installing `ansible` on RHEL 6.6.

Ansible is a radically simple IT automation engine that automates cloud provisioning, configuration management, application deployment, intra-service orchestration, and many other IT needs. For more detail, hop over to docs.ansible.com.

Written on October 6, 2015
linux ansible hadoop rhel centos


Creating a passwordless entry on Centos 6.5.

You can enter a linux system without entring a password using below steps. We will be creating a ssh jey which will be share between the servers, which will be used to authenticate. This is also a secure way of connecting to server, as the private key is inside the user home directory and can only be accessed by the user.

Written on March 19, 2015
linux centos rhel


Creating a Multi-node Cassandra Cluster on Centos 6.5.

The Apache Cassandra database is the right choice when you need scalability and high availability without compromising performance. Linear scalability and proven fault-tolerance on commodity hardware or cloud infrastructure make it the perfect platform for mission-critical data. Cassandra’s support for replicating across multiple datacenters is best-in-class, providing lower latency for your users and the peace of mind of knowing that you can survive regional outages.

Written on March 19, 2015
hadoop linux cassandra centos rhel


KVM Installation on CentOS 6.x.

KVM is a kernel-based Virutal Machine which grows quickly in maturity and popularity in the Linux server market. Red Hat officially dropped Xen in favor of KVM since RHEL 6. With KVM being officially supported by Red Hat, installing KVM on RedHat-based systems should be a breeze.

Written on February 18, 2015
linux kvm centos rhel virtual-machine vmware


Installing `zabbix-java-gateway` on Centos 6.5

Zabbix 2.0 adds native support for monitoring JMX applications by introducing a new Zabbix daemon called Zabbix Java gateway. Zabbix Java gateway is a daemon written in Java. When Zabbix server wants to know the value of a particular JMX counter on a host, it asks Zabbix Java gateway, which uses the JMX management API to query the application of interest remotely. The application does not need any additional software installed, it just has to be started with -Dcom.sun.management.jmxremote option on the command line.

Written on February 9, 2015
zabbix linux java zabbix-java-gateway centos rhel nagios monitoring


Installing NodeJS on Centos 6.6.

Node.js is an open-source, cross-platform runtime environment for developing server-side web applications. Node.js applications are written in JavaScript and can be run within the Node.js runtime on OS X, Microsoft Windows, Linux, FreeBSD, IBM AIX, IBM System z and IBM i.

Written on February 6, 2015
linux webserver nodejs centos rhel


Simple Script to create a user on centos 6.5

Default passwd is set as username@123 As we are setting the chage, user needs to change the passwd on first login.

Written on January 27, 2015
linux create user centos rhel