Sending bulk emails with Postfix and Haproxy

Scale UP Postfix servers The ever increasing business complexity demands the need of sending bulk emails. Typically the MTA’s available nowadays are not capable of sending emails at rate which a business organization actually needs. There only few exceptions available such as PowerMTA but they will cost you a lot of money. This article will [&hellip

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Block DDOS with Haproxy and Nginx

Layer 4 and Layer 7 attcks Those who experienced DDOS attacks knows how hard it is to mitigate them. Well this tutorial is not going to concentrate on mitigating a DDOS attack completely, but blocking Layer 7 attacks on application layer with upto 100000 simultaneous connections. When you receive a layer 4 attack that counts [&hellip

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DKIM and SPF Setup in Postfix:-

Enabling SPF checks in Postfix:- SPF is an e-mail anti-forgery technology the enables domain owners to list, in the Domain Name Service (DNS), authorized sources of mail from their domains. It enables mail receivers to reject mail that does not come from authorized sources. Package installation:- Install the following package in the server. Integrating with [&hellip

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Top 40 yum commands in linux

YUM Stands for Yellowdog Updater, Modified. In this document we’ll see how to install, remove, upgrade new packages using YUM. In addition to the above, YUM has got many features and lets see them one by one. 1. Install a package To install a package, do ‘yum install packagename’. This will also identify the dependencies [&hellip

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Top 20 rpm commands in Linux

RPM stands for Red Hat Package Manager. RPM keeps the information of all the installed packages under /var/lib/rpm database. In this document lets go through some of the important rpm commands which make our life easier. 1. Get the list of installed packages # rpm -qa where q – Query a – All 2. Query [&hellip

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ASR – Automatic System Recovery

What is ASR – Automatic System Recovery ? ASR (Automatic System Recovery ) is an advances System Recovery Mechanism available in HP servers. Supported Hardware platform includes : ProLiant and Blade Servers. This ASR feature is implemented using a “heartbeat ” timer that continually counts down. The Health Monitor frequently reloads the counter to prevent [&hellip

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Redhat to Cent OS Migration

Convert RHEL to CentOS Some people would love to move on to Cent OS as long as they are not concerned about the Official Redhat Support and the Signed packages from the RHN repository. Today lets review the steps for converting a live Redhat Server into Cent Os with a very short process. The process [&hellip

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Top 10 HPASMCLI Commands

Manage HP Proliant Server with HPASMCLI Utility. HPASM is the management tools package for the HP Proliant server series. It can be used to display the System or Bios setting as well as the hardware status of the Proliant servers. The utility is very useful in the automation jobs as the CLI can be included [&hellip

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