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Postfix Basic Configuration Introduction Postfix has several hundred configuration parameters that are controlled via the main.cf file. Fortunately, all parameters have sensible default values. In many cases, you need to configure only two or three parameters before you can start to play with the mail system. Here's a quick introduction to the syntax: Postfix configuration files The text below assumes that you already have Postfix installed on the system, either by compiling the source code yourself (as described in the INSTALL file) or by installing an already compiled version. This document covers basic Postfix configuration. Information about how to configure Postfix for specific applications such as mailhub, firewall or dial-up client can be found in the STANDARD_CONFIGURATION_README file. But don't go there until you already have covered the material presented below. The first parameters of interest specify the machine's identity and role...

Installing, removing, and updating packages is a typical activity on Linux. Most of the Linux distributions provides some kind of package manager utility. For example, apt-get, dpkg, rpm, yum, etc. On some Linux distributions, yum is the default package manager. Yum stands for Yellowdog Updater Modified. This article explains 15 most frequently used yum commands with examples. 1. Install a package using yum install To install a package, do ‘yum install packagename’. This will also identify the dependencies automatically and install them. The following example installs postgresql package. # yum install postgresql.x86_64 Resolving Dependencies Install 2 Package(s) Is this ok [y/N]: y Package(s) data still to download: 3.0 M (1/2): postgresql-9.0.4-5.fc15.x86_64.rpm | 2.8 MB 00:11 (2/2): postgresql-libs-9.0.4-5.fc15.x86_64.rpm | 203 kB 00:00 ------------------------------------------------------------------ Total ...

To find information about your devices and current partitions run: # dmesg | less # dmesg | egrep -i 'cd|dvd' # fdisk -l Use the first command to identify the USB device name. Mount CD/DVD ISO or DVD ITSELF Type the following command to mount Fedora 12 iso image: # mount Fedora-12-x86_64-netinst.iso -o loop /media/cdrom0/ # DVD=/media/cdrom0 # ls -l $DVD Sample outputs: total 6 dr-xr-xr-x 3 root root 2048 2009-11-09 05:37 EFI drwxr-sr-x 3 root 499 2048 2009-11-09 05:37 images drwxr-sr-x 2 root 499 2048 2009-11-09 05:36 isolinux You need to use files stored in isolinux directory to create a bootable usb pen. Format Usb Create the fdisk partition : # fdisk /dev/sdb You need to create only 1 partition. Next format the partition: # USB=/media/usb # mkdosfs /dev/sdb1 Finally mount the partition: # mkdir -p /media/usb # mount /dev/sdb1 /media/usb # USB=/media/usb Copy Required Files Type the following commands: # cp -av $DVD/isolinux/* $USB # cd...

Installing an SSL Certificate in Windows Server 2008 (IIS 7.0) Microsoft's new server platform, Windows Server 2008 uses Internet Information Services (IIS) 7.0 . This new version makes big changes in the way that SSL certificates are generated, primarily making it much easier than previous versions of IIS. In addition to the new method of requesting and installing SSL certificates, IIS 7 includes the ability to: Request more than one SSL certificate at a time Import, export, and renew SSL certificates easily in IIS Quickly create a self-signed certificate for testing This article will walk you through the process of ordering an SSL certificate from a commercial certificate authority and installing it on an IIS 7 Windows Server 2008 machine. Create the Certificate Signing Request The first step in ordering an SSL certificate is generating a Certificate Signing Request . This is very easy to do in IIS7 using the following instructions. Click here to hide or show the ima...

Active Directory Data Store (Directory) The Active Directory data store is the database that holds all the directory information such as information on users, computer, groups, other objects, and information on the objects which users can access. It also includes other network components. Another name used to refer to the Active Directory data store is the directory. The Active Directory data store or directory is stored on the hard disk of the server by means of the Ntds.dit file. The file has to be stored on a drive that is formatted with the NTFS file system. The Ntds.dit file is placed in the Ntds folder in the systemroot. When changes are made to the directory, these changes are saved to the Ntds.dit file. Because all the data in Active Directory is stored in one distributed data store, the availability of data is improved. A centralized data store means less duplication, and also needs less administration. Because domain controllers are utilized to manage domains, each domai...

What are trust relationships In the Windows NT domain model, domains had to be bound together through trust relationships, simply because the SAM databases used in those domains could not be joined. What this meant was that where a domain trusted another Windows NT domain, the members of the domain could access network resources located in the other domain. Defining trust relationships between domains eliminates the need for an Administrator to configure user accounts in multiple domains. In a trust relationship, the two domains are referred to as the trusting domain and the trusted domain. The trusted domain is the domain where the trust relationship is created. The trusting domain is the other domain specified in the trust, that is, the one wherein network resources can to be accessed. The trusting domain in this case recognizes the logon authentications of the trusted domain. The logon trust relationship is supported by the NT LanMan Challenge Response. This allows pass-through au...