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Showing posts from June, 2017

LDAP Server & Client : How to Setup OpenLDAP Server and Authenticate Client Workstation

How to Setup OpenLDAP Server and Authenticate Client Workstation LDAP or lightweight directory access protocol allows anyone to locate and connect to organizations, peoples and other resources like files and devices in a network (public/private). LDAP follows X.500 standard, a standard for directory service in a network that typically uses usual client/server paradigm. LDAP is lighter because in its initial version it did not include security features. The primary use of directory services is storing users and object data in a central system and make this data available to other applications mainly for authentication or as an address book and we can accomplish this using an OpenLDAP Server. This articles covers how to Setup OpenLDAP server and authenticate client workstation using Lightweight directory access protocol in Ubuntu 16.04 This articles covers how to Setup OpenLDAP server and authenticate client workstation using Lightweight directory access protocol in Ubu

Network Monitoring - How to Setup Naemon Networking Monitoring Tool in Linux

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How to Setup Naemon Networking Monitoring Tool in Linux Naemon is an Open Source system and network monitoring application which watches hosts and other services that you specify, alerts you when things go bad and notifies you when they get better. Naemon is based on Nagios 4.0.2 and aims to be a drop in replacement for Nagios. Naemon Suite is currently roughly equivalent to Nagios Core, which makes Naemon Core the equivalent of "Nagios Core Core". Naemon is the general term of the entire "Naemon Suite" that consists of two different parts, Naemon Core and the Thruk Monitoring web interface. We will generally refer to naemon Suite as just Naemon. In this article, we will install naemon in centos 7 and ubuntu 16.04 and explore its usage in Centos via NPRE. Features of Naemon → Monitoring of network services  like SMTP, POP3, HTTP, NNTP, PING, FTP etc.) → Monitoring of host resources (processor load, disk usage, memory usage etc.) → Simple plugin

Network Monitoring : Linux ntopng - Network Monitoring Tool Installation (Screenshots)

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Linux ntopng - Network Monitoring Tool Installation (Screenshots) Nowdays computers are connected between each other. From the small area such as your home Local Area Network (LAN) until the the biggest one which we call - Internet. When you are managing a network computer, you are managing one of the most critical component. Since most of developed application is web based application, the network between critical. There is why we need a network monitoring tool. One of the best network monitoring tool is called ntop. From Wikipedia “ ntop is a network probe that shows network usage in a way similar to what top does for processes. In interactive mode, it displays the networkstatus on the user's terminal. In Web mode, it acts as a web server, creating a HTML dump of the network status. It supports a NetFlow/sFlowemitter/collector, a HTTP-based client interface for creating ntop-centric monitoring applications, and RRD for persistently storing traffic statistics ”

File Size ??? 6 Ways to Find Largest Top Files and Directory in Linux

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File Size --:????????????????? 6 Ways to Find Largest Top Files and Directory in Linux Finding the size of large file and directories in Linux servers is one of the most important tasks that every system administrator came across in his daily tasks. So, every system administrator must know about multiple ways to find out the size of larger disks and files consuming the hard disks. Sometimes, it becomes more important, when your system's disk are getting filled so rapidly and you have to discover which files or directories are are ingesting up, all of your disk area on a Linux. In this case, we should be able to find a particular directory location where the data is being filled up. As there is no such shortcut command which is available to discover the largest documents or directories on a Linux or UNIX file system but there is some possibility by using some command line utilities that can help us reaching to the source location. So, this article will help you to

Gateway to Gateway - Intro to Configure IPsec VPN (Gateway-to-Gateway ) using Strongswan

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Intro to Configure IPsec VPN (Gateway-to-Gateway ) using Strongswan Strongswan supports Gateway-to-Gateway (site-to-site) and Road warrior  types of VPN. In first type, network traffic is encrypted/decrypted on the gateway (entrance/exit) of an organization. However in Road warrior case, traffic encrypted from the end client (machine) to remote end gateway. In this article, we will explain creation of  tunnel between two sites of an organization to secure the communication. Strongswan based VPN server/gateway placement is shown in the following figure. We want to secure communication between 10.1.0.0/16 and 11.1.0.0/16 networks of organization. As shown in the above figure, we are interested to secure the communication from A to B and vice versa. It is important to make sure the routing of Strongswan based VPN Gateways in the organization network. We assume that machine from  office A can ping a machine in the network of B office . This will ensure the connectivity