posted Jan 27, 2012 8:03 PM by Paul Valentino
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updated Jan 27, 2012 8:33 PM
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So far, this has been a year dedicated to a rewarding career transition, continuing to build up the vCommunity Trust and updating my certifications rather than maintaining my blog. I have achieved my EACOE Enterprise Architecture Certification, my first EMC Proven Professional
EMCCIS Certification and have three more exams scheduled between now and Feb. 24th ( plus on-site intructor led Vblock training the week of the 14th ). It's safe to assume that the #vTrust site as well as this one will be neglected for a short while. Therefore, your contributions of training materials and lab guides are wanted now more than ever (See http://www.vcommunitytrust.org ). My goals for after the exam on Feb. 24 are to resume building some lab guides for more VCP 5 related material plus real world use cases for AppSense Management Center & Enterprise Manager, VMware View & ThinApp; Citrix Netscaler, Branch Repeater, XenDesktop, XenApp, and Provisioning Servers/Appliances. It would also be nice to get some guides from the community for any of the topics mentioned on the vProfessional Training materials page on the #vTrust site. You are welcome to submit materials that are not mentioned on that page as well keeping in mind that the goal is infrastructure training in general - not vendor or technology specific. Additionally, at some point in the near future we hope to have the remainder of requirements for the hands-on lab environment ( FC Switch/es as well as disks and trays compatible with FAS 3020 or another storage solution ), so we'll be installing that into ipHouse ( Thanks to Mike Howarth! @geekandi ) once we have everything we need.
Hopefully I pass all my exams on the first attempt and don't incur any more delays which will impact generating #vTrust content. Wish me luck :)
And keep your eyes open on Feb. 6th around 12PM CST - I should be providing another update then.
Also, if your register for your EMCISA and get your Starter Kit using my Advocate information all proceeds will be donated to vCommunity Trust. See the PDF attached below. My Advocate Information: Paul Valentino pvalentino@vcommunitytrust.org CertTracker EMC ID: EMC326927 |
posted Jan 3, 2012 10:13 AM by Paul Valentino
posted Dec 22, 2011 6:37 PM by Paul Valentino
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updated Dec 22, 2011 6:37 PM
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Many students and community members around the world that are eager to gain experience with infrastructure technologies including virtualization, compute, network and storage are currently lacking key resources including access to hands-on lab resources and affordable training materials.
While we’ve managed to maintain 0% administrative costs and overhead, made possible by Google Apps for Nonprofits and contributions from vCommunity Trust volunteers, there is still a critical gap to be filled for providing lab resources. Not only will the completion of the lab environment provide hands-on access for students and community members, but it will also provide the resources to develop essential training materials and valuable lab guides. To that end, we already have the datacenter hosting, compute and virtualization resources required for a lab which will support approximately 25 students concurrently; however, we still are lacking the storage and networking components required to make this initial lab a reality. Will you kindly help us to meet our goal of providing hands-on lab resources for 25 concurrent users as well as the foundation for providing additional training materials to the general public free of charge?
There are many ways you may contribute to this cause and we greatly appreciate your support. We will honor your gift by including your name or logo within our training materials and on our website so that our students and visitors to our site will know you’ve invested in the global community’s technical education. Contributions are welcome in the form of cash donations by mail or through our site at http://www.vcommunitytrust.org/donations, equipment donations mailed to 30883 Montclair Dr, Lindstrom, MN 55045, and/or transferring the rights of technical training materials created by you to vCommunity Trust Inc.
Your gift will have a significant impact for increasing interest, awareness and knowledge of new technologies and enable individuals from all walks of life to embark on a successful career in technology. The ability to have hands-on experience with advanced technologies, we feel, is the best way to prepare individuals for the workplace and we thank you for partnering with us and our students to make this a reality.
Sincerely, 
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posted Nov 4, 2011 7:16 PM by Paul Valentino
posted Aug 6, 2011 8:36 AM by Paul Valentino
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updated Dec 21, 2011 10:45 PM
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Even though we knew very little about nonprofit organizations, we were confident that we would be able to figure things out with the help of the community. We were right; individuals like @clinek, @SirStan and others came forward to help review our 1023 Application and other business documentation. As a result, we were able to avoid many common pitfalls that companies face when starting a nonprofit organization. Also, the majority of our efforts were coordinated through social media outlets such as twitter and facebook. We have board meetings using Skype due to the distributed nature of our team; we use twitter, facebook, blogging and google apps extensively for providing updates, collaborating on documentation or disseminating information. We've had the great pleasure of participating in a podcast with our good friend @Niketown588 and with the crew over at vSoup.net. The vCommunity Trust would not and could not exist in its current form without all of these resources and contributions from the community.
The Office of the Secretary of State and MN Council of Nonprofits websites proved to be key resources for helping us to determine the requirements for establishing a nonprofit 317A corporation in the State of Minnesota. The IRS web site proved invaluable for information regarding establishing a 501(c)(3) nonprofit organization in the US. Furthermore, one of the greatest forms of assistance came from reviewing examples of other nonprofit 1023 applications, Articles of Organization and Bylaws. Many examples of these documents were found on the web and through friends who are members of nonprofit organizations. Of course, we needed to apply our own business plan and mission when drafting our business documents but the examples provided a wealth of direction for satisfying all of the required elements, especially in the case of the attachments to the 1023 Application.
After choosing our name we needed to confirm that it was available; although it was only required that the name be available in MN, we did a more extensive search to ensure that we wouldn't have any conflicts with naming for companies in other areas of the world. We also had to make sure that we wouldn't have any problems registering our domain name. To confirm availability in MN we used the Name Availability tool on the Secretary of State website. Once we completed the global name search and felt comfortable that we wanted to move forward with the name, we filed a name reservation form online with the required fee of $45.00 (rate as of September 20, 2010). We also filed for our EIN online with the IRS taking extra care to follow the instructions provided that are specific to nonprofit organizations seeking a 501(c)(3) designation.
We spent a few days researching the requirements and reviewing examples of nonprofit organizations Articles of Organization and Bylaws keeping in mind that we intended to apply for 501(c)(3) tax exempt status with the IRS. Amazingly, we had a fully drafted and reviewed set of documents which we submitted on September 23, 2010 along with the required $80.00 fee. On September 24th, 2010 we obtained our Certificate of Incorporation as a Minnesota nonprofit formed under section 317A. The key thing to remember with your business filing is that it must be renewed every year to maintain a nonprofit status; in our case we must go to the Minnesota Office of the Secretary of State site Online Annual Renewal Filing page to stay current with our filing. No renewal fee is required unless a name change, address change, or registered agent change dictates an Amendment to the Articles which will result in a $45 fee. Similarly, we must file form 990 annually with the IRS and may be eligible to file e-postcard 990-N if donations continue to remain below $25,000 per year.
Soon after obtaining our 317A the fun really began. We spent the next three months completing the 1023 Application for 501(c)(3) with all of the required attachments. When you view the document links below it will be fairly obvious why three months rather than three days were required. With business plan in hand and all the relevant examples we could find, we plugged away and were able to submit our 1023 files on January 11, 2011 with the required $400 fee (fee could be larger for company expecting greater income). Then the waiting game began; the IRS processes 1023 Applications on a first come first serve basis so the time to wait will vary based upon volume of applications.
Now it is worth noting that even if you file the appropriate change of address forms with the IRS, the department processing your 1023 application wont get that update and inevitably continue sending notifications to your old address, so be sure to send a copy of any change of address forms to the address you sent the 1023 Application to, or if you've already been assigned an agent you may send them a fax with the information (Can you tell that we don't know this from our personal experience :-). Once our agent was assigned, the process was rather painless as she proved to be very helpful. We simply needed to file one Amendment for Article IV (If you copy the verbiage from this Amendment rather than using what we submitted in original Articles above you can save this step and the $45 fee that goes with it) and answer a few simple questions. Once we faxed all the information back it was only a matter of a couple of weeks before we received our letter of determination. Once we did receive the letter it was only a matter of a couple days after providing the required documents to the merchants before we got our Donation buttons up and running again for both Google Merchant and PayPal.
Yay! On August 4th, 2011 the LOD arrived stating we are officially a tax exempt nonprofit public charity.
Some other considerations were the creation of a website and establishing nonprofit merchant accounts for accepting donations. We chose Google Sites and Google Apps in an effort to ensure no monthly administration fees and for its ease of use. So far we've been perfectly willing to accept the limitations for customization of our site because we'd much rather not have to rely on public donations to cover any expenses other than certification and training costs. In hindsight, it would have been better to wait for our letter of determination before establishing merchant accounts because they ended up disabling our ability to accept donations shortly after we were setup because we did not have a letter of determination yet. It did not help matters that we sent all of our filings and a copy of our submitted 1023 Application to the merchants either.
We wanted to ensure that public donations would primarily service the needs of the candidates and we're proud to say that less than $30 of our donations to date have been used for administrative expenses. The board of directors contributed all of the fees for the 1023 Application and all of the business filings; we only needed to utilize a small amount of the donations to obtain certified copies of our business documents for banking purposes. This is also a factor for choosing not seek paid professional services but rather volunteer professional services. Our primary purpose is to further the cause of education and get people certified in a way that ensures real world success; therefore, we gratefully accept volunteer assistance from qualified professionals to meet our goals.
We hope you find this information useful and of value. If so, please consider making a financial, VMware Training Credit, software, and/or hardware donation. Every contribution helps tremendously.
Regards,
Paul Valentino - Chairman vCommunity Trust Inc. @vcommunitytrust @sysxperts |
posted Jul 20, 2011 12:24 PM by Paul Valentino
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updated Sep 27, 2011 11:17 PM
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I've recently confirmed that as far as kernel parameters go there are none so valuable for performance when set correctly as in the case of the two mentioned in the title of this post. The improvements are especially noticeable on systems with large amounts of memory, but I wouldn't ignore them in cases of normal memory allocation either. And, that's not to say that others like kernel.shm??? net.core.* or fs.* are not important, I'm simply saying that all things equal I have never seen more profound improvements in performance by adjusting a kernel parameter than I have with these two related to the Page Cache. This has held true for me whether it be an Oracle Database server or a JBoss application server, a physical machine or a virtual machine. So that begs the question, "What are these dirty_ratio and dirty_background_ratio and why do they have such a significant impact?" To answer that question we first must understand that the page cache on a Linux system is the area where filesystem based I/O is cached and that these settings affect how the cache is utilized by the kernel, more specifically, tuning pdflush for how much RAM based cache to use for (dirty pages) data targeted to disk and for how frequently to flush that cached data by writing the pages back to disk. Dirty pages are the pages in memory (page cache) that have been updated and therefore have changed from what is currently stored on disk. So getting into the detail of these settings I will first say that there are other settings related to pdflush and many other posts that go into the gory details so I shall focus on these two settings since they are the only ones I've ever had to manipulate in order to improve performance or eliminate a crippling bottleneck. The first setting vm.dirty_background_ratio is found in /proc/sys/vm/dirty_ratio and can be set by echoing a value to that location as in: echo 5 > /proc/sys/vm/dirty_background_ratio or by updating /etc/sysctl.conf by adding vm.dirty_background_ratio = 5 and then running sysctl -p vm.dirty_background_ratio is the maximum percentage of ((Cache + Free) - Mapped) memory that can be dirty before it is written to disk by the pdflush process. In other words, if you have 256G of RAM and are using the default value of 10 for dirty_background_ratio then the system will probably never attempt to flush the cache based upon this setting. The value of dirty_expire_centisecs (default of every 30 seconds) will hopefully kick in to initiate a pdflush well before the 10% mark is reached. The second setting vm.dirty_ratio is found in /proc/sys/vm/dirty_ratio and can be set by echoing a value to that location or by updating /etc/sysctl.conf with vm.dirty_ratio = 5 for example (default value is 40). vm.dirty_ratio is the value that represents the percentage of MemTotal that can consume dirty pages before all processes must write dirty buffers back to disk and when this value is reached all I/O is blocked for any new writes until dirty pages have been flushed. Therefore, in the case of the 256G of installed RAM and the default setting of 40% for this value, you will see the pdflush process kick in at approximately 100G of dirty pages resulting in blocked I/O for as much as several minutes at a time. Just do a dd to a large file and watch ls -la /largefile to see the lengthy pauses. Again, dirty_expire_centisecs will kick in before the cache grows this large but 30 seconds is a very long time for a system under heavy I/O. You will most likely experience debilitating I/O problems with the default values on systems with large amounts of memory. Before we progress to changing any values it's pertinent to get a good baseline during periods of peak activity for the targeted workload, so if this is a JBoss server I want a baseline during a period where it is most actively being used by the users for its primary purpose and not during the backup window. (Note that changing these settings will most definitely impact the way backups work so you will also want to verify that impact and make adjustments accordingly, more info at end of post) The best way to see the pdflush activity on a systems is by watching the relevant vmstats: watch grep -A 1 dirty /proc/vmstat # Dirty Pages and writeback to disk activity
You might also like to have atop installed as it provides very good insight into the status of your page cache. Right around the 4th row of output you can see the cache and dirty pages info. At the same time you will also want to capture some iostats, netstats, vmstats etc. for your baseline. In this way you can see how the pdflush settings changes are impacting your overall system performance as you make them. Similarly you can watch the proc filesystem to capture Cache and dirty pages stats if you prefer: watch grep ^Cached /proc/meminfo # Page Cache size
watch grep -A 1 dirty /proc/vmstat # Dirty Pages and writeback to disk activity
watch cat /proc/sys/vm/nr_pdflush_threads # shows # of active pdflush threads
First I add the new values to /etc/sysctl.conf but do not update them:
vm.dirty_background_ratio = 5 vm.dirty_ratio = 5
Then, I prefer to get things cleaned up by freeing up pagecache, dentries and inodes and then performing the update to settings by running the following: sync; echo 3 > /proc/sys/vm/drop_caches; sysctl -p
On a system that has been crippled by the default settings I will typically start with the settings above and then go through several iterations of capturing metrics while changing only the vm.dirty_background_ratio by 1 until I find a sweet spot. I seem to always end up staying with a value of 5 for the vm.dirty_ratio but you may also want to go through the same steps to confirm the sweetest spot for that value as well.
As mentioned earlier, changing these settings will most likely have a negative impact on your backup performance unless your system has similar I/O characteristics to the backup solution you are using. It will be in your best interests to monitor your backup window before and after each change. For me, I often end up offloading any large file backups to an alternate server and adjusting the backup software's client cache settings in addition to making the changes above. The end result in my cases has been about 25% average performance improvement; I've seen as high as a 50% increase in I/O performance on high transaction systems and as much as 40% for batch processing activity by manipulating these values.
Help out a future vProfessional in need by donating to vCommunity Trust Inc. today! |
posted Nov 16, 2010 12:37 PM by Paul Valentino
posted Sep 21, 2010 8:02 PM by Paul Valentino
posted Sep 21, 2010 7:56 PM by Paul Valentino
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updated Sep 21, 2010 8:00 PM
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Have confirmed with our NS-480 that anything less than 8 drives will not work for Fast Cache when using 200G SSDs. We had 7 unallocated 200G SSDs and Unisphere just threw error that there is no supported SSD drive configuration. Consensus seems to be that smaller drives are better for Fast Cache anyway and will support more configurations: As in Appendix A of doc link below: | Model | Fast drive capacity (GB) | Number of Drives | | cx4-480/ns-480 | 200 100 73 | 8 4 4 | | cx-960/nx-960 | 200
100
73 | 10 or 20
8
8 |
Hot Spares are optional but recommended. Note that the specification sheet for the ns-480 states that only 73G, 200G, and 400G SSD/EFD drives are supported so that should be verified as well before going out and buying 100G SSD. Cannot confirm those statements yet, as I do not have the smaller SSD drives, but plan is to move the 200G drives to pool and allocate 4 new 73s to the Fast Cache. According to friends, almost any combination is possible although dependent upon metadata structures and size limits. See http://www.emc.com/collateral/software/white-papers/h8046-clariion-celerra-unified-fast-cache-wp.pdf for more details on Fast Cache Make special note of the section "Best practices when you have limited number of Flash drives" on page 17, while also making note that in the simplest of terms, Fast Cache is great for bursty traffic while it's not so great for sequential traffic. |
posted Aug 12, 2010 7:10 AM by Paul Valentino
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updated Aug 13, 2010 7:59 PM
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If, like me, you want to hang out with the best and brightest in the industry :) you will want to attend the following:
| 8/28 | 6pm | vChow | Alioto's | #aliotosvmworld on Twitter | Attendees and Spouses welcome |
| 8/29 | 6-7pm | #MNtweetup | Thirsty Bear | #MNtweetup | Attendees who want to network with MN Tweets |
Incredible list of locations provided by @ericsiebert - SF Things to Do restaurants, sites and cigar bars
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