Showing posts with label Computer. Show all posts

Wednesday, April 29, 2009

My Twitter Account

Welcome to my site..

I just wanted to let you know that

I have my twitter account now....

http://twitter.com/NandaLinnAung

i have 1500+ followers and I basically get 100 unique visitors per week, depending on how much URL I announce. But i don't spam much, and always put my personal things, or what i am currently doing... but yes, it's pretty good technique.

If you want to build very fast follower network, just follow my followers, 100 persons a day.. because twitter has a follow limit and you don't want to get banned.

Thursday, September 18, 2008

Wiki how to

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32 SEO Tips to Boost your Website Traffic

Search Engine Optimization (SEO) is the process of improving the volume and quality of traffic to a web site from search engines via “natural” (”organic” or “algorithmic“) search results for targeted keywords. Usually, the earlier a site is presented in the search results or the higher it “ranks”, the more searchers will visit that site. SEO can also target different kinds of searches, including image search, local search, and industry-specific vertical search engines.

By carefully evaluating techniques required to boost website traffic i have come up with the 32 tips for search engine optimization (SEO) of your favourite website. If these tips are followed in correct manner you will see the increase in traffic for sure

1. Make sure your site is not under construction, incomplete, with little or no unique content.

2. When your site is ready, submit it to Google, Yahoo, MSN and ASK.com. Consider also submitting to other search engine but most of them are powered by these four leading search engines. Submit also your site to reputable high PR web directories, open directories, yellow pages and social bookmarking sites such as del.icio.us, furl, etc.

3. Submit your sitemap to Google, Yahoo, MSN and ASK.com (sitemap for search engines usually in XML format)

4. Offer sitemap to your site visitors for easy page navigation. (sitemap for visitors in HTML format)

5. Create unique and rich content sites. Avoid duplicate content. Do not create multiple pages, sub-domains, domains, mirror sites or sites with different domain names but same content.

6. Check your keywords and make sure they are relevant and actually are contained in your site. Avoid keywords stuffing.

7. Use text instead of images in your content, links and important subjects.

8. Make your TITLE and ALT tags descriptive, simple and keyword rich. Avoid irrelevant and repeated keywords.

9. Title tag should be 60-80 characters maximum length.

10. Meta tag description should be 160-180 characters including spaces. (about 25-30 words)

11. Meta Tag keywords must be 15-20 words maximum.

12. Optimize Pages with Headings (H1, H2, H3..) containing your site’s primary keywords.

13. Validate your CSS and HTML. Check for errors and broken links.

14. If your site contains dynamic pages(i.e., the URL contains a “?” character), make sure you use SEO friendly URLs. Search engines’ spiders having difficulty indexing dynamic pages.

15. Maximum links per page must be fewer than 100. Avoid the risk of being flagged as link farm by search engines.

16. Use Lynx as text browser to check your site. (http://lynx.isc.org/)

17. Allow search bots (good ones) to crawl your sites without session IDs or arguments that track their path through the site. Using these techniques may result in incomplete indexing of your site.

18. Check your web server/host if it supports the If-Modified-Since HTTP header. It tells search engines whether your content has changed since last crawled your site. It will save you bandwidth, resources and avoid server overload.

19. Use Robots.txt file to manage and control search engine spiders in indexing your site. You can allow and disallow spiders and choose directories you want to be crawled and indexed. But with bad bots or spam bots you need to modify your HTACCESS file to properly and effectively manage bots or spiders. Visit http://www.robotstxt.org/wc/faq.html to learn more about Robots.txt file.

20. Do not attempt to present different content to search engines than what you show to your site visitors.

21. Avoid dirty tricks and exploiting loop holes to improve search engines ranking.

22. Avoid links to bad neighborhood such as web spammers, link farms, phishing, hacker, crack, gambling, porn and scam sites. Linking to them will greatly affects your search engine rankings.

23. Do not attempt to join in link schemes, excessive reciprocal links or excessive link exchanging and link exchange web rings.

24. Do not use unauthorized programs or online tools to submit your site, check page rankings and other automated queries. Avoid the risk of being flagged as spam.

25. Do not use hidden text and links. Show to search engines what you show to your vistors. It will greatly affect your site’s reputation.

26. Do not attempt to create pages that contains phishing, scam, viruses, trojans, backdoors, spyware, adware and other malicious programs.

27. Make your site useful and informative.

28. Improve your link building. Link to high PR websites. Quality of relevant links are far more important than quantity. Links will greatly improve your site’s visibility, popularity and rankings. Search engines consider links as votes to your site.

29. Check your page link structure. Every page should be reachable by a single static text link.

30. Be extra careful in purchasing SEO services. Some uses illegal and questionable ways to improve rankings.

31. Do not buy or sell links.

32. Do not create sites that contains purely affiliate links and no valuable content that are useful to the users.

source: Edwin Reyes

Hackers claim to break into Palin's Yahoo Mail account

A group of hackers that hit the Church of Scientology's site earlier this year have apparently cracked the Yahoo Mail account belonging to Gov. Sarah Palin, the Republican nominee for vice president, according to documents and screenshots posted on the Web.

A security expert called the practice of using private e-mail accounts "incredibly dangerous" for public officials such as Palin.

The group, which calls itself "Anonymous," announced that it had gained access to Palin's Yahoo account in a message last night to, a site that regularly posts confidential documents. Among the files that WikiLeaks had posted for download were five screenshots from gov.palin@yahoo.com, an address book and two digital photos of Palin's family.

One of the account's screenshots shows a short exchange in July between Palin and Lt. Gov. Sean Parnell, who is running against Democrat Ethan Berkowitz for Alaska's lone congressional seat. In her reply, Palin called Anchorage-based conservative radio host Dan Fagan "inconsistent and purposefully misleading" in his comments about Parnell.

Another screenshot displays the text of a message to Palin from Amy McCorkell, whom Palin appointed to the Governor's Advisory Board on Alcoholism and Drug Abuse in October 2007. According to a press release issued by Palin's office at the time, McCorkell was previously a private legal investigator, an office worker and a fitness instructor and, like Palin, lives in Wasilla, Alaska.

In the message dated Sunday, McCorkell said: "I am reading the paper and have thoughts and prayers going your way ... don't let the negative press wear you down! Pray for me as well. I need strength to 1. keep employment, 2. not have to choose. Lately I just pray may God's will be done."

The day before, The New York Times had published a story critical of Palin's hiring practices as governor. The story did not mention McCorkell but said that Palin had appointed at least five former high school classmates to state positions since she took office.

Palin has come under criticism for using private e-mail accounts to conduct state business, with some alleging that she and others in her administration have used them to skirt message-retention and public records laws. The Bush administration has been accused of doing the same thing.

"Using private accounts for government or business use is incredibly dangerous," said Adam O'Donnell, director of emerging technologies at message security vendor Cloudmark Inc. "There's a reason why you have an official account. It's so that you can apply proper security management to the account."

Earlier this year, the Anonymous group launched several attacks against the Web site of the Church of Scientology, claiming that it wanted to "save people from Scientology by reversing the brainwashing."

The Republican National Committee and the McCain-Palin campaign had no immediate comment.

source: Gregg Keizer

Self-healing storage explained

Ever wonder what the number one cause of drive failures is? Answer: Nothing.

That's right. Nothing. Drive manufacturers report that some 70% of the drives they get returned from makers of disk arrays have nothing wrong with them. Why? Because heat and vibration can cause intermittent errors in storage arrays, and the only remedy that array manufacturers have for these intermittent errors is to fail the drive.

Why does this matter to you, a storage administrator? The drive is under warranty, so why should you care? Here are three reasons why you should.

A drive failure costs you time: packing the drive, arranging for the manufacturer to pick it up, buying more hot spares to replace the ones just consumed, installing them, labeling them, and so on. If there's one thing a busy storage professional does not need, it's more paperwork.
You suffer the performance degradation and time penalty of doing a RAID rebuild (up to tens of hours for deep drives). During this RAID rebuild, you run the risk of a second drive failure (probably also an erroneous false positive) and, as a result, could suffer a complete data loss and a roll-tape event (a system failure where you have to redcover all the data from tape).
Although no one will ever admit that they have done this, you risk the possibility of physically removing the wrong drive (which can also lead to complete data loss and another roll-tape event).

The fundamental role in any storage system -- reading and writing of data -- is performed by disk drives. Any interruption of this basic task has a ripple effect across all aspects of storage management by reducing performance, requiring human intervention and increasing the risk of service outage or data loss.

A storage system that itself could automatically resolve erroneous disk drive failures would save everyone time and money, and eliminate the introduction of unneeded risk into the storage environment. What can be done to make a system self-healing?

Modifying the drive enclosure
The best way to heal a drive is to avoid failure conditions in the first place. Before dealing with any of the software issues, it makes sense to modify the physical enclosure to make sure you are eliminating potential causes of failure. Today's systems can place 12 or more drives (all powered on) in an off-the-shelf 3U chassis. This creates heat and vibration. Reducing heat and vibration are the two biggest steps a supplier can take to improve drive reliability.

Excessive drive vibration is caused by the way today's external arrays are put together. Drives are tightly packed into a single drive bay, then mounted on drive sleds for easy access and removal. This means the drives are all mounted, the disks are all spinning, and the heads are all seeking in the same direction. But all this results in excessive harmonic vibrations, which lead to enough read/write errors to presume a drive failure. These "failed" drives often end up working properly once they are sent back to the drive manufacturer.

Vibration can cause the drive that is vibrating too much to fail. It can also cause neighboring drives to skip on reads or writes, hence the external controller will designate them as failed. This second issue is of real concern because it can cause a double drive failure by first failing a drive in an adjacent slot and then failing itself. Double drive failure on a RAID 5 system requires that data be restored from another source, such as tape. No rebuild is possible at this point.

Drive makers can minimize vibration by rigidly packing the components so there is less movement from the spinning drives as well as designing the individual drive bay or housing so that it has the same rigidity throughout. Often in hot swap systems, the drive bay is looser in the front than the back, which amplifies vibrations for the front half of the drives.

The only way manufacturers can significantly reduce drive vibration is to redesign the way their drive shelves are packed. There are two ways they can do this. First, the drives must counter-rotate (meaning they must be installed front to back), alternating throughout the array shelf. Doing so naturally dampens vibration and reduces or eliminates enclosure torque. Two companies that counter-mount their drives are Xiotech and Copan Systems.

The second step is to build a better drive shelf and drive sled system that provides more consistent rigidity so the drives cannot vibrate. The combination of these two techniques can reduce vibration significantly.

Minimize heat buildup
The second method of precluding a drive failure is to minimize heat buildup. Manufacturers can do this by increasing and improving airflow in the drive enclosure. When you see how tightly packed most drive enclosures are, you may wonder how they get any airflow across the drive surfaces. One solution is to stop putting all the drives side by side in the front of a drive bay. Staggering the placement deeper into the drive bay increases airspace between drives, thereby improving airflow and reducing vibration.

A storage system that itself could automatically resolve erroneous disk drive failures would save everyone time and money, and eliminate the introduction of unneeded risk into the storage environment.

While the physical redesign of the array hardware layout can significantly reduce the amount of failures upfront, other drive failures can be addressed by increasing the intelligence of the array system so it has the ability to heal itself.

The easiest step in creating a self-healing array is to power-cycle the drive (akin to rebooting a desktop workstation), which usually fixes the problem. In the case of a self-healing drive system, the first attempt to repair a drive that is showing signs of failure is to automatically reset or power-cycle the drive in a manner that has little or no impact on normal operations. The key is to have the whole process performed within the application time-out thresholds, using cache to manage I/Os during the recovery. Once the drive comes back on, it is tested to see if it is operating normally. If so, it is returned to service. This can all be made to happen without user intervention.

Most of the time a simple reset or power cycle will fix the problem. While most array systems and controllers cannot do this, companies like Xiotech are leading the charge.

Process of remanufacturing
If the drive reset/power cycle does not clear the problem, a self-healing system should have the ability to go through a complete remanufacturing process. This includes recalibrating the heads, performing a low-level format and rewriting servo (control) tracks. In most cases, the steps of power-cycling the drive and performing the remanufacturing process will bring the drive back online, saving the storage administrator significant time and expense.

A drive enclosure that reduces heat and vibration, combined with drive remanufacturing capabilities, should eliminate most drive failures. But drive failure can still occur in even the most drive-friendly environments. If a drive does eventually fail, the next logical step is to fail smart. The three aspects of failing smart include:

Recovering data at a granular level, such as failing a surface instead of a whole drive if a head fails. This minimizes the amount of data that has to be copied out or rebuilt to reduce the time it takes to recover.
Putting the intelligence for drive and RAID management into the drive enclosure. Rebuilds are highly processor-intensive; putting the horsepower to manage the rebuild at the drive enclosure level distributes the load for the RAID rebuild process and allows I/O destined for other enclosures to proceed unimpaired. This also ensures that unnecessary delay is not placed onto other production workloads.
Improving spare-in-place technology. Having drives that sit idle and are always powered-on wastes capacity and energy. With today's technology, there is no need for a drive to be a hot spare. Spare capacity should be spread across all available drives in the array, allowing for maximum use of that capacity (i.e., use all the drives to handle the workload, not just the non-spare drives), while minimizing further power consumption.

Today's IT environments require a highly reliable foundation of storage where most failures are prevented. . .and if not prevented, then resolved in place. A self-healing array that eliminates up to 70 percent of drive failures and can then cover the remaining legitimate failures will increase system administrator productivity and minimize overall data vulnerability.

About the author: George Crump

Brad Pitt tops list of Internet malware lures

Movie star Brad Pitt has shovedParis Hilton off the top of a list neither wanted to be on. A fan entering Pitt's name in a search engine now has a startling one in five chance of finding a malware-hosting site instead, says security products companyMcAfee Inc.

Pitt is on top of the fake Web site malware league, just ahead of a collection of pop and film stars that reads (in descending order) Beyonce, Justin Timberlake, Heidi Montag, Mariah Carey, Jessica Alba, Lindsay Lohan, Cameron Diaz, George Clooney and Angelina Jolie.

Hilton no longer even makes the fake Web site top 10, but can perhaps take some solace from her continued popularity with spammers.

If you've never heard of some of these people, then it's a fair bet that you are not the intended target of a technique that for some years has been one of the most common ways to infect a PC. But still it persists, driven by an apparently insatiable appetite among some Internet users for computer screensavers, wallpaper and ringtones that feature their favorite stars, at whatever risk to themselves.

"Cybercriminals employ numerous methods, yet one of the simplest but most effective ways is to trick consumers into infecting themselves by capitalizing on Americans' interest in celebrity gossip," said McAfee spokesman Jeff Green. "Tapping into current events, pop culture or commonly browsed sites is an easy way to achieve this."

Reading the latest statistics, it's hard to avoid the conclusion that malware writers think that the celebrity-obsessed are as recklessly naive as they are star-struck. Most malware-infection techniques have shown some evolution over the past two years, but the fake Web site ploy just goes on and on.

In fact, a deeper problem is the way users interact with search engines, as was pointed out by McAfee itself only a year ago. McAfee's motives for publicizing the issue may not be entirely neutral; at least one search engine,Yahoo, recently began using McAfee's SiteAdvisor tool to filter the Web sites it returns in search boxes.

And for those users who visit only Web sites they know are legitimate, there is also bad news. The biggest hack trend of the last year has been compromising perfectly legitimate Web sites to serve malware -- witness this week's large attack on the Web site of BusinessWeek magazine.

For Internet users, there is no easy escape, only the awareness of the growing number of pitfalls.

source: John E. Dunn

Wednesday, September 17, 2008

TechEd: SAP terms on the rise

SAP terms that are "cool" to use

BBD -- Business ByDesign is the formal name for SAP's on-demand product for the "lower midmarket" -- filling the gap between small companies that might run Business One and larger midmarket companies that would probably run All-in-One. When it announced BBD, SAP noted that it would leverage the eSOA (enterprise service-oriented architecture) landscape. The overall success of BBD probably rides on the broader challenges facing the Software as a Service (SaaS) market, which has struggled mightily but does have some recent success stories like the rise of Salesforce.com. It remains to be seen whether SAP can add another chapter to the book of SaaS wins.

Business Process Expert -- Business process expert (BPE) is the term SAP is using to describe the next-generation consultant who will be needed to implement the SAP systems of the future and fulfill the eSOA vision. BPEs will come from both technical and functional SAP backgrounds. Consultants who want to become BPEs will need to integrate their IT and business skills into one skill set, not unlike the way companies are merging IT and business agendas in order to stay competitive. More information on becoming a BPE is available atSAP's Business Process Expert homepage.

eSOA -- Formerly called ESA, Enterprise SOA (service-oriented architecture) is SAP's own customized, business-process-centric version of the standard SOA developed by the TOGAF open standards group. If you've missed the buzz on eSOA, stay tuned -- there will surely be another batch of press releases issued shortly.

NetWeaver Process Integration (PI) -- Formerly called Exchange Infrastructure, NetWeaver 7.1 now features PI, SAP's integration hub and a vital part of SAP's Enterprise SOA. The success of PI depends on whether companies will be willing to switch from whatever messaging systems they are already using. The feeling here is that PI will survive the performance tests and will eventually be a frequently used part of SAP's overall architecture.

NetWeaver CE (Composition Environment)-- This is SAP's new development environment, which is based on the Java EE 5 architecture and includes cutting-edge modeling tools. NetWeaver CE ships with NetWeaver 7.1, but the good news is that NetWeaver CE is now available on theSAP Developer Network, so aspiring CE developers can roll up their sleeves and practice their technique right now. CE is part of SAP's intentional shift into the age of modeling, where manual coding will be de-emphasized in favor of visual modeling and business process modeling. Welcome to the age of "composition and reusability."

SAP Certified Master -- "Certified Master" is the top tier of SAP's new three-tier certification program. According to this new program, you can get an "Associate Certification" (the equivalent of the "classic" SAP certification) or a "Professional Certification" (one tier higher in skills). Sometime in 2008, SAP will also offer the "Certified Master" level.

The launch of the "Certified Master" program has been delayed because this will be the first certification from SAP that is likely to involve more than a sit-down test. Some type of hands-on or field evaluation is slated to be included, and how that will be accomplished has yet to be hammered out. Over time, these advanced certification levels could have an impact on the market. On the positive side, these higher-level certifications could help independent SAP consultants achieve an extra level of perceived credibility when applying for project openings. On the down side, we have heard from consultants who view the new SAP certifications as a "cash grab." Perhaps wait-and-see is the best attitude for now.

SAP OCM Toolkit -- SAP OCM stands for SAP "Organization Change Management." I'm probably the only one who is into this particular term, so be careful tossing "OCM" around if you expect someone else to understand you. The reason I am including it here? First, because I was impressed to learn that SAP's Solution Manager now ships with a complete, step-by-step OCM Toolkit to follow throughout the implementation. This is an incredibly helpful roadmap for addressing the "human side" of an SAP installation at each place where changes in roles and organizational structure may be encountered. I also included this term because Solution Manager itself is becoming a key part of the SAP landscape, and so, by getting a handle on the "SAP OCM Toolkit," we're also getting a firmer grip on Solution Manager -- a product to stay on top of for anyone with a stake in SAP.

Switch Framework -- SAP's term for the new ability customers have, as of ERP 6.0, to turn on the industry solutions they need. All of SAP's 25+ industry solutions ship with ERP 6.0. One of the genuine "Gee whiz -- that is kind of neat" moments at TechEd came with a live demonstration of how to turn on and tweak an industry solution in real time. The average SAP professional won't be encouraged by his company to fool around with the Switch Framework, but it's still pretty nifty. The big deal is that SAP is shipping all the Industry Solutions at once, allowing companies to activate the functionality without having to track different release schedules.

Web 2.0 -- SAP uses this term so much we're all forgiven if we temporarily thought SAP had created it. "Web 2.0" is the ultimate technology cocktail term because everyone knows what it means yet nobody can define it. Be on the lookout for "Enterprise 2.0," a sister term implying the use of Web 2.0 in the corporate enterprise.

Since Web 2.0 has more definitions than any other term in use, we're not going to define it here, except to say that the idea of leveraging the Web for the purposes of building intelligent communities is something that SAP has done a better job of than many of its customers. How many of SAP's own customers have a community with almost a million members obsessing over its every move and providing valuable input, much of it on a volunteer basis?

The critical question is: How does Web 2.0 fit into eSOA? That's a topic for a longer article, and you'll find many different answers. As a general rule, the Web 2.0 concept of "mashups" has definitely had an impact on SAP's own Enterprise Services vision. We can go further and predict that the integration of third-party "best of breed" content services, such as the mashup of external demographic trends with internal customer data, is one of the "killer apps" of the eSOA era. For now, we're safe in using the term "Web 2.0" even if we don't know exactly what we're talking about -- because nobody else does either.

Jon Reed is an independent SAP analyst who writes on SAP consulting trends.

The green data center 2.0: Beyond best practices

For the past three years, green computing has been on the IT agenda, and many companies have implemented best practices to become more energy efficient. Data centers now use hot aisle/cold aisle and install blanking panels to avoid mixing air. IT pros have consolidated workloads with server virtualization and they've boosted server utilization from single-digit percentages.

Nonetheless, as CPU and storage demand outstrip progress, IT energy consumption grows unabated. Incremental improvements in cooling and server efficiency won't be enough to avoid the coming power and carbon crisis. This special report with links to resources helps explain why data center energy use is about to hit the wall and illustrates the next steps for companies to go beyond the basics. Additonal resources on data center power consumption can be foundhere.

TABLE OF CONTENTS
I. Data center energy hits the wall
II. Next steps in data center design:
III. What can IT do about the problem?

I. Data center energy hits the wall
Here are some statistics from a recent McKinsey & Co./Uptime Institute report on data center energy use:

Data center energy use doubled between 2000 and 2006. And by 2012, it's expected to double again.
For many industries, data centers are one of the largest sources of greenhouse gas emissions.
Between now and 2010, U.S. demand for data center energy will require the equivalent of 10 new power plants.

These numbers might not mean much on paper, but these factors will coalesce into a spike in utility prices that will drastically change the patterns of our energy use. For starters, during the next presidential administration, climate change legislation and carbon emission regulation will be a reality in the U.S. Each candidate has pledged to enact global-warming legislation, and the bipartisanAmerica's Climate Security Act of 2007 is currently in Senate committee and it could be voted on as soon as June 2008.

This legislation would impose a cap-and-trade system on utility companies, raising the price of power an estimated 20% across the board. Data center operators already constrained by huge power bills are in for even more sticker shock at the meter in the future. Click here for more on cap and trade's impact on the data center.

While proposed legislation would require utility companies only to track and reduce carbon emissions, some data center managers like Michael Manos at Microsoft expect the Environmental Protection Agency (EPA) to start monitoring the carbon emissions of all U.S. businesses.

"There are massive efforts afoot in government and regulatory agencies," Manos said in an interview at AFCOM. "The CEO of the company will have to start reporting carbon emissions and energy usage, and that [responsibility] is going to be shifted to the IT department that maintains the data centers. Most data center professionals haven't thought about this today. …It's not a question of if, but when, it is coming and what metrics will be required to report on this. It'd be far better for the people who run and operate data centers to come up with metrics that mean something."

And as mentioned, if the McKinsey/Uptime estimates are correct, the U.S. will need to build 10 new power plants over the next two years. The permitting process for these projects won't even be complete by 2010, let alone the power production. According to Andrew Fanara, who heads the Energy Star product team at the EPA, the data center industry could face a power shortage, which would increase energy costs further. Data centers are tethered to the grid -- and as energy issues become more challenging, there is risk for any business that depends on the grid. For more on the topic, listen to this podcast on energy security with Fanara.

II. Next steps in data center design
Faced with the following challenges, an incremental approach to data center energy efficiency isn't going to cut it -- which is why forward-thinking companies now architect radically different data centers from those of just a few years ago.

Beyond blanking panels: Ultra-efficient data center cooling. For years, hot-aisle/cold-aisle, raised-floor cooling has been the standard method of cooling servers. But forced-air cooling is one of the least efficient systems in data center infrastructure, and wasting cold air is the most common mistake in data center management. You can set up hot aisle/cold aisle, install blanking panels, and seal gaps in the floor, but you probably still waste cold air in places you wouldn't expect.

Some experts and data center pros have taken the same thermodynamic principles behind hot-aisle cold aisle to the extreme. One way to address wasted cold air is better containment either at the hot-air return or the cold aisle, using plenum systems to contain hot or cold air in a closed-loop system.

Jeff Lowenberg, the vice president of facilities at the Houston-based hosting company the Planet has taken steps to create a more isolated hot-aisle/cold-aisle design. He extended the return-air plenums on computer room air conditioning (CRAC) units. "Hot air naturally rises, so the CRAC units are sucking air in from the hottest part of the data center," Lowenberg explained. "By extending the plenums higher, it ensures that the CRAC units are not sucking in any cold air from the cold aisles, as it allows for the hottest air to be sucked into the units. In this scenario, the top of the plenums must be at least 2 feet from the ceiling."

While this system is not a closed loop, for the Planet's next data center buildout, Lowenberg plans to extend the plenums through the ceiling, using the area above the ceiling tiles as a return air path. Click here for photos and a full report on the Planet's data center operations.

Economizers gaining traction in data center industry. There are two methods for using outside-air temperatures to remove heat from your data center: air-side economizers, which actually bring cold outside air into the facility, and water-side economizers, which use outside air temperatures to replace chiller systems.

Unfortunately, most data centers don't take advantage of free cooling because they aren't located in a region that stays cold long enough for the system to pay for itself or they lack the automation to manage going on and off the plate-and-frame heat exchanger. Luckily the American Society of Heating Refrigerating and Air-Conditioning Engineers Technical Committee 9.9 has considered expanding the recommended temperature and humidity range for servers, allowing users to benefit from economizers during more days of the year.

Also, more companies are getting on board with economizers and proving they work. Foster City, Calif.-based hosting company Equinix Inc. touted economizersat the 2008 AFCOM Data Center World conference. And Joe Parrino, the data center manager of United Parcel Services of America Inc.'s Windward data centerin Alpharetta, Ga., has also used water-side economizers with huge success.

Lastly, computational fluid dynamics (CFD) tools are becoming more prevalent in data centers and can have a huge impact on cooling efficiency. News writer Mark Fontecchio recently published a special report on CFD tools and current market offerings. SearchDataCenter.com also published a new study from IDC Architectsoutlining how to use CFD analysis on the outside of a building to evaluate whether economizers are a good fit for your data center.

III. What can IT do about the problem?
The IT administrator can have a huge impact on energy consumption, but there have to be incentives for IT to address the problem. So far, the incentives have been weak. In 2006, VMware Inc., partnered with California utility companies to offer rebates for server virtualization projects, but SearchServerVirtualization.com reports that the Northern California utility Pacific Gas & Electric Co. (PG&E) has given out only four rebates so far.

Implementing server virtualization can result in significant savings. Estimates by VMware and PG&E Co. state that direct energy savings for each server removed via server virtualization runs between $300 and $600 per year.

Looking for efficiency at the operating system level. IT pros also look for energy savings at the operating system level by shutting down servers when they're idle or running them more efficiently. Intel has partnered with the Linux community to launch the LessWatts.org site, which offers downloadable power diagnostic tools, white papers, frequently asked questions, and user-contributed tips and ideas. SearchEnterpriseLinux.com recently reported on the initiatives in the open source community on LessWatts.org.

Microsoft recently built new power management features into Windows Server 2008 to allow servers to throttle down when they're not fully utilized.

With all these individual operating system features becoming available, it's only logical that OS providers would begin competing on efficiency, but as news writer Pam Derringer discovered, pinning down energy-efficiency ratings on operating systems is trickier than it seems.

Specifying efficient servers. For the past several years, IT executives have had the idea that it's OK to continue buying cheap hardware. Meanwhile facilities executives face double-digit growth rates of energy-guzzling, poorly utilized servers showing up on raised floors. But now that capacity planners have hit a wall in data centers across the U.S., the paradigm is shifting.

When it comes to buying servers, performance is still king, followed by price. But energy efficiency is gaining ground in the conversation, thanks to new specifications that allow users to quantitatively measure performance per watt.

Just as the EPA has created Energy Star labels for desktop computers and ceiling fans, it is now finalizing a label for servers. Server energy consumption and performance would be measured and tested by third parties, and the top 25% of energy-efficient models would garner the Energy Star label. The determination would enable data center managers to weigh energy efficiency alongside other factors in their purchasing decisions. The EPA recently released its draft of the server specifications for its Energy Star program for servers.

Measurement: The holy grail of data center energy efficiency. What kind of metrics do you need to manage data center energy consumption? It doesn't have to be a 28-point formula. Experts advise data center managers to pick a simple measurement, create a ratio and improve on it.

"Pick something, any metric, and get started," said Pitt Turner, principal, senior project leader and president of Computer Site Engineering Inc. "Even if you pick the wrong metric -- as long as you improve it -- you can drive tremendous changes!"

There are a lot of potential variables to measure, which is where many data center managers get bogged down. But you don't need to swallow the ocean in your first attempt to gauge your data center's efficiency. You can take a simple approach to measure how much of your data center's power actually goes to IT equipment (i.e., servers, storage and network gear) and how much is sucked up by air conditioners and lost in AC/DC (alternating current/direct current) conversions at power equipment.

This measurement is expressed as a ratio and is most commonly known as power usage effectiveness (PUE) and has been accepted by vendor consortiums like the Green Grid, the EPA and ASHRAE as a useful figure to measure data center efficiency. PUE is determined by taking the power "in" to the data center (measured at the utility electric meter), divided by power "out" used to run the IT equipment for computing. The equation looks like this:

PUE = total facility power ÷ IT equipment power

For a complete rundown on how to start measuring your data center energy efficiency, check out Turner's webcast "Implementing energy-efficiency metrics in data centers."

Be a green hero. Once you've become a pro at managing IT energy use, you can sign up to help the EPA get a handle on data center energy consumption nationally. Check out the EPA's National Data Center Energy Efficiency Information Program.

Matt Stansberry is SearchDataCenter.com's senior site editor.

SELinux in RHEL 5: More enhanced, more security

Security Enhanced Linux (SELinux), an open source project sponsored by the National Security Agency to help implement mandatory access controls (MAC), was first introduced in Red Hat's distribution with Red Hat Enterprise Linux 4 (RHEL 4). In our review of RHEL 4 and SELinux in 2005, we were excited about the possibilities and the GUI interface that came with SELinux, but we were cautious about the software package's ability to capture the market. Despite the user-friendly GUI, SELinux was difficult to configure and hard to understand. The documentation wasn't much help either. Most administrators were just turning off SELinux.

Red Hat clearly understood that some changes were necessary. They were either intimidated by its complexity or feared the possible damage that a poorly configured system could do to their applications. On RHEL 4, there was no easy way to determine why, if an application stopped working, whether or not the problem was due to SELinux.

Red Hat hopes to change this with several new features and enhancements in RHEL 5. New monitoring tools, multilevel security integration, policy modules and utilities will provide RHEL 5 users the added security of SELinux with less difficulty.

SELinux Troubleshooter
One of these enhancements is the new SELinux Troubleshooter. Written in Python, setroubleshoot is a tool that watches the audit log files for access vector cache (AVC) messages and sends reports when things go bump in the night. The daemon continuously watches audit logs for errors and then translates them into laymen's terms for you. SELinux denials were one of the most common problems that administrators reported, which is why most decided to deactivate SELinux. Another daemon, setroubleshootd, receives connections which examine the data and alerts listeners. This tool maintains its own log file, under /var/log/setroubleshoot, and includes the use of the sealert command. This is a GUI desktop notification function, which contacts setroubleshootd, the local server daemon, and essentially registers itself as an alert listener.

To begin, start the browser:
# sealtert –b

This system is made up of three components, including the alert feature, setroublesoot and the audit subsystem. The audit subsystem reports the actual AVC messages. When the kernel sends a message that SELinux denies authorization for something, it creates this AVC message. Each message is tagged into a denial event, which setroubleshoot can assemble into complete events. The tool merges all these independent messages into single denial events.

New domains, policy modules
The extent that SELinux monitors the operations of services in RHEL 5 has significantly increased since the last version. In RHEL 4, only 15 services had domains defined, while in RHEL 5 more than 200 target services are governed by the SELinux system. It is recommended that every program shipped by Red Hat and started on boot should have a domain defined. The benefit here is that it is much less likely for processes governed under SELinux running on RHEL5 to be compromised, increasing the comfort of security administrators. Another benefit is the introduction of policy modules, which make the process of modifying SELinux policies much easier. In RHEL 4, one had to go through many steps (downloading source, editing code, using make) to rebuild the policy tools. With policy modules, these setups are not necessary. The audit2allow utility gives you the ability now to generate policy modules (allow rules) directly from audit.log messages. One can also configure these polices using the system-config-selinux utility. This much improved GUI lets you modify the policy you need changed from a set of pre-defined parameters. Also, it is very easy to change system policies. You no longer need to edit configuration files, you only need to check or uncheck boxes. This is available out of the box and is fully integrated with RHEL5.

You can also use the semanage utility to configure elements of these polices without any recompilation of policy sources. The semodule command is another useful one. For example, this command lists out the policies:

[root ((Content component not found.)) _29_137_21 selinux]# semodule -l amavis 1.1.0 ccs 1.0.0 clamav 1.1.0 dcc 1.1.0 evolution 1.1.0 iscsid 1.0.0 mozilla 1.1.0 mplayer 1.1.0 nagios 1.1.0 oddjob 1.0.1 pcscd 1.0.0 pyzor 1.1.0 razor 1.1.0 ricci 1.0.0 smartmon 1.1.0

Multi-level security integration
Another important enhancement is the multi-level security (MLS) integration into RHEL5. This model allows RHEL5 to get EAL4+ LSLPP certifications, which means that RHEL5 is now considered a trusted OS and can be sold to Government agencies which require the tightest security polices. MLS allows users to label files with categories. To turn the system into a trusted system in RHEL 5, install the policy (using the selinux-policy-mls utility) and make changes to the selinux config files to reference MLS. Prior to MLS, there was Type enforcement (TE), which is the primary mechanism and role based access control (RBAC). I'm still not thrilled about the fact that Red Hat still does not have a special SELinux guide for RHEL5. If Red Hat is really going to make SELinux an important part of its distribution, it needs to provide strong documentation so users do not have to fumble through the web looking for pieces of information. While there have been major improvements and tighter integration between RHEL5 and SELinux, Red Hat still has a way to go before it is user friendly enough for most IT departments. Better documentation will help in their efforts. The small chapter in the RHEL deployment guide (Chapter 43, Security and SELinux) isn't enough.

Deploying SELinux
Let's look at the Z parameter. Many utilities such as ps, lsof and netstat are optimized for SELinux, using the Z parameter.

[root ((Content component not found.)) _29_137_21 selinux]# ps -aeZ | more LABEL PID TTY TIME CMD system_u:system_r:init_t 1 ? 00:00:01 init system_u:system_r:kernel_t 2 ? 00:00:00 migration/0 system_u:system_r:kernel_t 3 ? 00:00:00 ksoftirqd/0 system_u:system_r:kernel_t 4 ? 00:00:00 watchdog/0 system_u:system_r:kernel_t 5 ? 00:00:00 migration/1 system_u:system_r:kernel_t 6 ? 00:00:00 ksoftirqd/1

Where SELinux is not installed, this is what you will see:

[root ((Content component not found.)) _29_137_21 selinux]# netstat -Z SELinux is not enabled on this machine.

We can also run the sestatus and genforce commands for further information on the status of SELinux on our system.

[root ((Content component not found.)) [root ((Content component not found.)) _29_137_21 selinux]# sestatus SELinux status: disabled [root ((Content component not found.)) _29_137_21 selinux]#72_29_137_21 selinux]# [root ((Content component not found.)) _29_137_21 selinux]# getenforce Disabled [root ((Content component not found.)) _29_137_21 selinux]#

How can we turn on SELinux when it is disabled? The simplest way is to edit the selinux config file and change the SELINUX parameter, which can take three values: enforcing, permissive and disabled. In our case, we made it permissive. This is the option where alerts will be sent, though polices will not yet be strictly enforced. I recommend this as a good first step towards SELinux deployment.

# This file controls the state of SELinux on the system. # SELINUX= can take one of these three values: # enforcing - SELinux security policy is enforced. # permissive - SELinux prints warnings instead of enforcing. # disabled - SELinux is fully disabled. SELINUX=permissive # SELINUXTYPE= type of policy in use. Possible values are: # targeted - Only targeted network daemons are protected. # strict - Full SELinux protection. SELINUXTYPE=targeted

After editing this file you must reboot your system in order for the change to take effect. Let's look at the status now, after the reboot.

[root ((Content component not found.)) _29_137_21 ~]# sestatus SELinux status: enabled SELinuxfs mount: /selinux Current mode: permissive Mode from config file: permissive Policy version: 21 Policy from config file: targeted

Perhaps the best new utility available is the system-config-selinux utility. Almost everything can be displayed or configured from here. If you are using X, make sure that you turn on x11 forwarding on your ssh client.

************************************************************* [root ((Content component not found.)) _29_137_21 ~]# system-config-selinux /usr/share/system-config-selinux/system-config-selinux.py:68: Warning: IA__g_object_get_valist: object class `GnomeProgram' has no property named `default-icon' xml = gtk.glade.XML ("/usr/share/system-config-selinux/system-config-selinux.glade", domain=PROGNAME)

SELinux and RHEL5 are a better marriage than SELinux and RHEL 4 ever were. The utilities are more focused, more user-friendly and more powerful. Setting up policies and administering the systems are easy and MLS, allowing this Linux distribution to be certified as a trusted system, is icing on the cake. Red Hat should publish more detailed documentation on SELinux and RHEL5: until that happens, I fear that administrators will continue to shun SELinux.

About the author: Ken Milberg is a systems consultant with two decades of experience working with Unix and Linux systems.