2. LVS: What is an LVS? Can I use an LVS?

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A Linux Virtual Server (LVS) is a cluster of servers which appears to be one server to an outside client. This apparent single server is called here a “virtual server”. The individual servers (realservers) are under the control of a director (or load balancer), which runs a Linux kernel patched to include the ipvs code. The ipvs code running on the director is the essential feature of LVS. Other user level code is used to manage the LVS (set rules for services handled, handle failover). The director is basically a layer 4 router with a modified set of routing rules (i.e. connections do not originate or terminate on the director, it doesn’t send ACKs etc, it’s just a router).

via 2. LVS: What is an LVS? Can I use an LVS?.

The director uses 3 different methods of forwarding.

  • LVS-NAT based on network address translation (NAT)
  • LVS-DR (direct routing) where the MAC addresses on the packet are changed and the packet forwarded to the realserver
  • LVS-Tun (tunnelling) where the packet is IPIP encapsulated and forwarded to the realserver.

AdditionalResources/Repositories/RPMForge

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The default RPMforge repository does not replace any CentOS base packages. In the past it used to, but those packages are now in a separate repository (rpmforge-extras) which is disabled by default.

You can find a complete listing of the RPMforge package packages at http://packages.sw.be/

via AdditionalResources/Repositories/RPMForge – CentOS Wiki.

The rpm at this link allows for yum to see the additional packages — such as alpine and perhaps others that were missing in the base.

H.P.’s TouchPad, Some Say, Was Built on Flawed Software

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From concept to creation, WebOS was developed in about nine months, this person said, and the company took some shortcuts. With a project like this, programmers typically start by creating the equivalent of building blocks that can be reused and combined to create different applications. But with WebOS, Palm employees initially constructed each app from scratch. Later, they made such blocks, but they were overhauled once by Palm and then again by H.P., forcing programmers to relearn how to build WebOS apps.

via H.P.’s TouchPad, Some Say, Was Built on Flawed Software – NYTimes.com.

How NASA’s GRAIL Probes Will Map the Moon’s Gravity

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How NASA’s GRAIL Probes Will Map the Moon’s Gravity Infographic | Moon Gravity, Phases & Facts | Moon Exploration & NASA Moon Missions, GRAIL Spacecraft | Space.com.

NASA’s twin Grail probes are designed to map the moon’s gravity field like no other spacecraft before. The $496 million mission will use the ultra-precise moon gravity maps to help scientists better understand the moon’s composition and structure, as well as how the moon evolved during its formation. Learn how the Grail mission works in the SPACE.com infographic above.

Facebook Leading, Microblogging Growing, World Connecting

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1 in every 5 minutes of time online is now being spent on social networking sites, up from a mere 6% in early 2007. The sites, led by Facebook, now reach 82% of the world’s internet-using population — about 1.2 billion people in total. This growth is happening across countries, with 41 of the 43 countries that the web measurement firm tracks showing penetration of 85% or more.

via ComScore’s 2011 Social Report: Facebook Leading, Microblogging Growing, World Connecting | TechCrunch.

How Samsung Just Screwed Over About 10 Million Of Its Android Phone Customers

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That means ~10 million people who bought the phone are going to be stuck on the outdated version 2.3 Gingerbread (or 2.2 Froyo in many cases) until they decide to drop more cash on a new phone.

via How Samsung Just Screwed Over About 10 Million Of Its Android Phone Customers – Business Insider.

It’s pointless to support old hardware on phones.  I wonder why this is even an issue?

This is an interesting point I didn’t know and relates to computer architecture.

It also demonstrates the inherent problem in Android phone manufacturers customizing the OS to the point where you can barely recognize Google’s original intentions for design and functionality. Those skins are such a tax on a phone’s hardware that it cripples functionality and makes it so all but the newest phones miss out on updates. So far, Samsung only guarantees Ice Cream Sandwich for its Galaxy S II phones. The Nexus S, which is also made by Samsung and shares similar hardware specs as many Galaxy S phones, will get the Ice Cream Sandwich update, but only because it uses a pure version of Android without the TouchWiz skin. Motorola only guarantees it for its latest Droid Razr. And HTC will issue Ice Cream Sandwich for the Rezoundsome time next year.