How to configure NIS server in Linux

Last Updated on Sunday, 4 September 2011 08:07 Written by A.Jesin Sunday, 4 September 2011 08:07

This article explains how to configure Linux as a NIS (Network Information Service) server. Both server side and client side commands are listed in this tutorial. NIS is a directory service which centralizes user administration. The instructions I outline here will work for Red Hat variant operating systems like CentOS, Fedora etc. NIS was originally called Yellow Pages or YP, but due to copyright issues it was renamed to Network Information Services (NIS). But still packages and services required for NIS start with yp. This tutorial will also explain the usage of autofs for mounting the home directories of users created on the NIS server. Read More…

How to make undeletable files and directories in Linux

Last Updated on Monday, 15 August 2011 07:30 Written by A.Jesin Tuesday, 12 July 2011 04:56

A very useful Linux tip on how to make files and directories undeletable even by the root user. You can apply this tip on all important configuration files so that no one accidentally or intentionally deletes it. To achieve this the chattr (Change Attribute) command is used it Linux. The chattr command “immunizes” the file not only from deletion but also modification. The chattr command does care about chmod values, even if a file has 777 permissions immunizing the file will prevent it from being deleted or modified. Read More…

Configure BIND DNS Split View

Last Updated on Monday, 13 June 2011 11:09 Written by A.Jesin Monday, 13 June 2011 11:09

Configure BIND DNS Views and Split to respond to different DNS clients with different answers based on their IP address. If you have many computers connected via LAN among which one is a web server, within the local network you may want domain names to resolve to private IP addresses and from the internet it should resolve to the public IP address. This can be done with BIND’s split-horizon feature. Based on a list of IP addresses of clients the DNS server replies with the appropriate answer. Take note that if you decide to configure split view all zones should come under a view. Read More…

Mount an ISO file in Linux

Last Updated on Thursday, 9 June 2011 02:03 Written by A.Jesin Thursday, 9 June 2011 02:03

This tutorial shows how to mount an ISO file in Linux. In Windows third party tools are required to mount ISO images, but in Linux a simple command is enough to mount ISO images. Before editing the /etc/fstab file please take a backup by following the given instructions. To mount an ISO image use the following command

mount -o loop /location/of/file.iso /mnt/file

Replace /location/of/file.iso with the actual location. The “file” directory inside /mnt must exist. This will mount the iso file for that session. If you want to permanently mount the ISO file modify the /etc/fstab file. Before doing this please backup the fstab file.

cp /etc/fstab{,.bak}

Now edit the /etc/fstab file and add the following line

/location/of/file.iso /mnt/file iso9660 loop 0 0

Save the file and execute the following command to remount all enteries in /etc/fstab

mount -a

This way you can mount as many ISO images you want.

Setup Linux DNS Server for Windows Active Directory

Last Updated on Wednesday, 1 June 2011 05:59 Written by A.Jesin Wednesday, 1 June 2011 05:59

Setup Linux BIND DNS server to work with Windows Active Directory. All you need to do is to allow updates from the active directory domain subnet and you’re good to go. Since this article involves more of Linux than Windows I’ve placed this article in the category Linux. First install a Windows Server OS and a Linux distribution, any Linux flavour will do. Install BIND DNS on the Linux server and do the necessary basic configurations. Read More…

Setup Secondary (Slave) DNS Servers Free

Last Updated on Saturday, 21 May 2011 12:31 Written by A.Jesin Saturday, 21 May 2011 12:31

Yes you read that right you can setup backup DNS servers for your domain without spending a penny. This tutorial will tell you how to do this. The primary (master) DNS server runs BIND in Linux OS, this process makes use of the free DNS hosting service provided by freedns.afraid.org, so you’ll have t0 setup the primary DNS server for your domain and allow the transfer of the domain’s zone records to ns2.afraid.org’s IP address. I assume you know how to setup a primary (master) DNS server in BIND, so I’ll show you how to edit the configuration files to allow zone transfers and to add a backup DNS server. Read More…