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.
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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.
In this post I will document my experience with both software and hardware RAID.
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Web server that use threaded processes such as Apache and others can be targeted using interesting HTTP DoS tool that has been released in wild. Tool can eat up all resources while it holds the connection open to server and keep sending incomplete HTTP requests. End result Apache run out of memory and comes under DoS attack.
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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
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.
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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.
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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?
=> Which browser did you switch to?
Linux does have directory server called OpenLDAP, but it requires good understanding and admin skills. MS-Ad has reputation for ease of use. Samba is a free software re-implementation of SMB/CIFS networking protocol mainly used by Microsoft. One of the goals of Samba version 4 is to implement an Active Directory compatible Domain Controller. Major features for Samba 4 already include:
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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.
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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.
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