nixCraft » Windows server

BIND 9 Dynamic Update DoS Security Update

Vivek Gite — Wed, 29 Jul 2009 15:47:12 +0000

BIND 9 is an implementation of the Domain Name System (DNS) protocols. named daemon is an Internet Domain Name Server for UNIX like operating systems. Dynamic update messages may be used to update records in a master zone on a nameserver. When named receives a specially crafted dynamic update message an internal assertion check is triggered which causes named to exit. An attacker which can send DNS requests to a nameserver can cause it to exit, thus creating a Denial of Service situation. configuring named to ignore dynamic updates is NOT sufficient to protect it from this vulnerability. This exploit is public. Please upgrade immediately.

Software Vs Hardware RAID

Vivek Gite — Tue, 07 Jul 2009 16:01:56 +0000

A redundant array of inexpensive disks (RAID) allows high levels of storage reliability. RAID is not a backup solution. It is used to improve disk I/O (performance) and reliability of your server or workstation. A RAID can be deployed using both software and hardware. But the real question is whether you should use a hardware RAID solution or a software RAID solution.

Slowloris DoS Tool: It Can Bring Down Apache 1.x/2.x

Vivek Gite — Fri, 19 Jun 2009 14:50:39 +0000

Apache Security Update - a flaw In Apache can be used to carry out DoS. Slowloris is a new Apache DoS tool which can use slow Internet links to bring down Apache servers, rather than flooding networks. Most D/DoS tool requires faster net connections but this tool works with minimal bandwidth. This tool can lead to a DoS attack on Apache 1.x, 2.x, dhttpd, GoAhead WebServer, and Squid, while MS IIS6.0, IIS7.0, and lighttpd are confirmed not vulnerable to this attack.

How A Microsoft Veteran Learned To Love Linux And Why It Matters

Vivek Gite — Thu, 18 Jun 2009 22:50:37 +0000

Great article.

"After The Software Wars", is a new book in which former Microsoft employee Keith Curtis explores the worlds of proprietary and free software. Quoting from the article:

While I came to not be all that thrilled with Fedora itself, I was floored merely by the installation process. It contained a graphical installer that ran all the way to completion, it resized my NTFS partition -- which I considered a minor miracle, setup dual boot, and actually did boot, and let me surf the Web. I didn't have a clue what to do next, but the mere fact that this all worked told me more about the potential of Linux than anything I had read so far. You cannot, by accident, build an airplane that actually flies.

=> How a Microsoft veteran learned to love Linux, and why it matters

Missing Memory

Vivek Gite — Fri, 13 Mar 2009 18:53:20 +0000

Today, I've upgraded total 8 servers from 4GiB to 8GiB to improve performance of system by inserting additional memory modules. We started each server and checked for memory count at console. All severs booted normally after the upgrade and services such as SMTP, NFS, CIFS, HTTP started as expected. Shortly, afterwords I got a call from help desk about pop3 server for slow performance.

Uninstall IE8 Under Windows 7

Vivek Gite — Thu, 05 Mar 2009 02:07:39 +0000

IE (Internet explore) was first released as part of the add-on package Plus! for Windows 95 in 1995. IE is fully integrated into MS operating system. IE has been subjected to many security vulnerabilities such as spyware, adware, and computer viruses. Removing Internet Explorer does have a number of consequences. Applications that depend on libraries installed by IE will fail to function, or have unexpected behaviors. A just-leaked build of Windows 7 lets users remove Internet Explorer (IE), the first time that Microsoft has offered the option since it integrated the browser with Windows in 1997.

Why Did You Switch From IE ( Internet Explorer ) ?

Vivek Gite — Wed, 11 Feb 2009 20:17:26 +0000

I was going though my server logs / Google Analytics settings and found that over 60% users are on MS-Windows. However, each and every month visitors are switching to Firefox or Google browser and so on. So I would like to know your reasons for making switch from IE to another browser. Why did you switch and which browser did you switch to?

Samba 4: Linux Active Directory Server

Vivek Gite — Tue, 20 Jan 2009 18:08:45 +0000

Linux does have directory server called OpenLDAP, but it requires good understanding and admin skills. Enterprise networks now have an alternative choice to Microsoft Active Directory (AD) servers, with the open source Samba project aiming for feature parity with the forthcoming release of version 4.

Leap Second To Be Added End Of 2008 And Its Impact On Clustered Computers / Network

Vivek Gite — Wed, 31 Dec 2008 20:28:25 +0000

Get ready for a minute with 61 seconds. Scientists are delaying the start of 2009 by the first 'leap second' a timing tweak meant to make up for changes in the Earth's rotation.

The aged Earth is slowing down in its daily rotation, at least in the current epoch. So a leap second is added (a one-second adjustment added) to our time. This year will be exactly one second longer.

Precise time measurements are needed for high-speed communications systems among other modern technologies such as clusters, GPS, networks. You need to make sure that you are running updated version of ntpd that support leap second for UNIX and Windows computers.

Top 10 Linux Virtualization Software

Vivek Gite — Wed, 31 Dec 2008 15:00:59 +0000

Virtualization is the latest buzz word. You may wonder computers are getting cheaper every day, why should I care and why should I use virtualization? Virtualization is a broad term that refers to the abstraction of computer resources such as:

Platform Virtualization
Resource Virtualization
Storage Virtualization
Network Virtualization
Desktop Virtualization

This article describes why you need virtualization and list commonly used FOSS and proprietary Linux virtualization software.

Download of the day: WordPress 2.7

Vivek Gite — Thu, 11 Dec 2008 04:32:57 +0000

Wordpress version 2.7 has been released and available for download. From the announcement page:

The first thing you'll notice about 2.7 is its new interface. From the top down, we've listened to your feedback and thought deeply about the design and the result is a WordPress that's just plain faster. Nearly every task you do on your blog will take fewer clicks and be faster in 2.7 than it did in a previous version.

What is new in Wordpress 2.7

For a visual introduction to what 2.7 is, check out this video (available in HD, and full screen):

Download the latest release of WordPress version 2.7, released on 10 December 2008.

HowTo: Authenticate Linux Clients with Microsoft Active Directory

Vivek Gite — Tue, 18 Nov 2008 08:22:16 +0000

Every IT shop has a mix of Windows and Linux system. Sometime you need to authenticate your Linux desktop system against Microsoft Active Directory service. You can save time, effort and IT infrastructure by sharing authentication server. This article explains how to setup the Linux desktop computers with Active Directory using Samba and winbind.

Linux VMWare Server 2: Start / Stop VMs From a Shell Prompt

Vivek Gite — Wed, 29 Oct 2008 07:02:41 +0000

You can easily start / stop / pause or take a snapshot from a shell prompt under a Linux / Windows host using vmrun command. This is useful if you do not want to run web interface for starting and/or stopping VMs.

RAID 5 vs RAID 10: Recommended RAID For Safety and Performance

Vivek Gite — Wed, 22 Oct 2008 12:48:43 +0000

A Redundant Array of Independent Drives (or Disks), also known as Redundant Array of Inexpensive Drives (or Disks) (RAID) is an term for data storage schemes that divide and/or replicate data among multiple hard drives. RAID can be designed to provide increased data reliability or increased I/O performance, though one goal may compromise the other. There are 10 RAID level. But which one is recommended for data safety and performance considering that hard drives are commodity priced?

Nagios: System and Network Monitoring Book

Vivek Gite — Sat, 18 Oct 2008 13:59:12 +0000

The convenience and reliability that monitoring programs offer system administrators is astounding. Whether at home, commuting, or on vacation, admins can continuously monitor their networks, learning of issues long before they become catastrophes.
Nagios, the most popular open source solution for system and network monitoring, is extremely robust, but it's also intensely complex.

Power Off Server Once In a While?

Vivek Gite — Sat, 11 Oct 2008 16:55:32 +0000

From my mailbag:

I turn off the PC at home or the office once in a while. Now, I've server at colocation center. Do we need to run server 24/7? I do reboot the server once a month. Is it advisable to completely power off a server once in a while instead of 24/7 running?

MySQL vs PostgreSQL

Vivek Gite — Thu, 09 Oct 2008 13:02:16 +0000

Useful comparison of MySQL and PostgreSQL open source database software. MySQL vs PostgreSQL is a decision many must make when approaching open-source relational databases management systems. Both are time-proven solutions that compete strongly with propriety database software.

The Google Way: Saving Electricity For Data Center

Vivek Gite — Wed, 01 Oct 2008 20:05:07 +0000

Learn from Google how to save electricity while serving millions of request across a globe. Google come up with 5-step approach to build efficient data centers.

How to Transfer PuTTY Sessions To Another Windows Machine

Vivek Gite — Tue, 09 Sep 2008 11:11:20 +0000

PuTTY is a terminal emulator application which can act as a client for the SSH, Telnet, rlogin, and raw TCP computing protocols. You can use putty for remote login or to control your router connected via serial devices.
By default PuTTY stores the session information in the registry on Windows machine. If you have several PuTTY sessions stored in one laptop and would like to transfer those sessions to another laptop, you need to transfer HKEY_CURRENT_USER\Software\SimonTatham registry key and value as explained below.

Midori OS: Microsoft Sees End of Windows Era

Vivek Gite — Mon, 04 Aug 2008 18:18:24 +0000

Midori operating system is the code name for a microkernel-based operating system written as managed code, being developed at Microsoft, mooted as a possible successor to Microsoft Windows by many. Midori will use the Internet to operate and data will be stored on central Microsoft server. It will remove the role of a single PC.