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By admin, March 21, 2011 12:42 pm

After several months of testing with real world loading, I would say the most optimized way to utilize your SAN storage is to enable Thin Provisioning at BOTH the Storage and Host.

• By enabling Thin Provisioning on Equallogic, you will be able to create more volumes (or luns) for the connecting ESX hosts to use as VMFS or RDM space for the connecting VMs.
• By enabling Thin Provisioning on ESX host, actually this is on VMFS to be exact, you will significantly gain VMFS space utilization and put more VMs on it, I was able to get at least 40 to 100% space saving on some of VMFS. It’s definitely great for service providers who always want to put those under-utilized VMs and group them together using Thin Provisioning.

One thing you need to constantly check is space will not grow over to 100%, you can do this by  enable vCenter Alarm on space utilization and stay alerted, I’ve encountered one time that a VM suddenly went crazy and ate all the space it allocated, thus tops VMFS threshold as well as Equallogic threshold at the same time. 

This is the only down side you need to consider, but the trade off is minimum considering the benefit you get when using Thin Provisioning at BOTH Equallogic and ESX Level.

Of course, you should not put a VM that constantly need more space over the time into the same thin provisioned volume with others.

Finally, not to mention it’s been proved by VMware that the performance penalty for using Thin Provisioning is almost none (ie, identical to thick format) and it’s amazing using VMFS is even faster than RDM in many cases, but that’s really another topic “Should I or Should I NOT use RDM”.

* Note: One very interesting point I found that is when enabling Thin Provisioning on storage side, but use Thick format for VM, guess what? The storage utilization ONLY shows what’s actually used within that VM, ie, if the thick format VM is 20GB, but only 10GB is actually used, then on thin provisioned storage side, it will show ONLY 10GB is allocated, not 20GB.

This is simply fantastic and intelligent! However, this still doesn’t help to over allocate the VMFS space, so you will still need to enable Thin Provisioning in each individual VM.

Sometimes, you may want to convert the original Thick to Thin by using vMotion the Datastore, another great tool without any downtime, especially if your storage support VAAI, then this conversion process only takes a few minutes to complete.

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By admin, March 16, 2011 10:24 pm

今天看到的一段新聞﹐這樣的事情看來只會在中國大陸發生﹐可憐的小牛Gallardo和中國人。看見沒有﹐拿著傢伙的工人砸著的時候竟帶有詭異的笑容﹐令我不寒而慄﹐難道中國人真的有根深蒂固的“小農”基因﹖I am not sure what Jeremy of Top Gear would say if he ever came across this news.

据车主介绍，2010年11月29日，这辆购入不久的跑车，就在青岛出现了发动机不打火的故障。车主与该公司青岛销售店联系后，车由青岛销售店委托的维修服务商安排的拖车运至指定的维修店。没想到的是，运至维修店后，不但发动机故障没有得到解决，车辆保险杠和底盘也受损断裂。

经多次维权仍不能圆满解决，车主决定砸毁这辆兰博基尼。昨日下午3：15，在青岛一灯具城门口，车主雇人将这辆价值300万的兰博基尼盖拉多跑车，砸得面目全非。

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By admin, March 15, 2011 5:43 pm

今天是我在香港討論區網球版的兩週年紀念。

在過去的兩年裡﹐跟超過120位朋友切磋過﹐他們幾乎都有自己的秘技和不同的打法﹐從他們的身上我學到了很多寶貴的經驗如冷靜的頭腦﹑完善的計劃﹑堅人的毅力﹑爆炸的力量等﹐這都使我本身的技術比兩年前有明顯的提昇﹐謝謝你們的參與令到每次的球聚都令人留連忘返。

希望今後的日子有更多的朋友和我一齊來享受Happy Tennis。

Some interesting statistics:

Courts Booked: ~180場
Tennis Balls: 60罐
Restring: 4次

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By admin, March 13, 2011 9:46 pm

After watching the demo of VMware vCenter Operations, I would say it’s just another monitoring and diagnostic tool besides the leading two: vfoglight from Vizioncore and Veeam Monitor from Veeam, nothing really special, but it does present the trouble ones in an intuitive way by using color icons.

Personally, I found Veeam Monitor Free Edition is already more than enough to identify the problem and find out where the latency is, the key is to look at the lowest or deepest layer, in other words, into VM itself, as the problematic VM is the most fundamental element causing the contention on Resorucs pool, ESX Host, vCenter, etc.

Then I ask myself why would VMware release such product while there are already two great products in the market? Well, I will leave this question to you in the comment.

Update Apr 5

I’ve tried the Free Xangati for ESX and don’t like it, it’s not as intuitive as Veeam Monitor.

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By admin, March 9, 2011 10:29 pm

Originally I thought we are going to have a small footprint and easy managed software finally arrived from Dell, but I was wrong totally.

After spending hours and hours of trying to install DMC 2.0 on Physical and VM, both failed multiple times, I finally gave up. It was a buggy software and not to mention the size of it (over 1GB) and the bunch of crap modules it’s trying to load to your server (there are more than 80 stages during the installation).

I would strongly recommend everyone with a common sense to avoid using this product even it’s free of charge. Simply because it’s way over complicated and the pre-requirement can make anyone big headache, took over 1 hour to install on latest hardware server and finally failed during installation!

I would rather use PRTG as the tool for my monitoring purpose and I was hoping DMC can do me only one thing (hardware failure alert), now I will skip it forever and never look back, I will depend on vCenter’s hardware monitoring and iDRAC’s alert to help me to achieve the same goal.

Bye Bye DMC 2.0, the crappiest software I’ve ever encountered since MS Commerce Server back then.

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By admin, March 5, 2011 5:15 pm

It’s a common question: “Are there any BIOS settings Dell recommends for VMware ESX/vSphere?” Primarily, Dell recommends reading and following VMware’s best practices. The latest revision (as of this posting) can be found in their article “Performance Best Practices for VMware vSphere™ 4.1”. Here are a list of additional points of interest specifically regarding Dell PowerEdge servers:

• Hardware-Assisted Virtualization: As the VMware best practices state, this technology provides hardware-assisted CPU and MMU virtualization.
  In the Dell PowerEdge BIOS, this is known as “Virtualization Technology” under the “Processor Settings” screen. Depending upon server model, this may be Disabled by default. In order to utilize these technologies, Dell recommends setting this to Enabled.
• Intel® Turbo Boost Technology and Hyper-Threading Technology: These technologies, known as “Turbo Mode” and “Logical Processor” respectively in the Dell BIOS under the “Processor Settings” screen, are recommended by VMware to be Enabled for applicable processors; this is the Dell factory default setting.
• Non-Uniform Memory Access (NUMA): VMware states that in most cases, disabling “Node Interleaving” (which enables NUMA) provides the best performance, as the VMware kernel scheduler is NUMA-aware and optimizes memory accesses to the processor it belongs to. This is the Dell factory default.
• Power Management: VMware states “For the highest performance, potentially at the expense of higher power consumption, set any BIOS power-saving options to high-performance mode.” In the Dell BIOS, this is accomplished by setting “Power Management” to Maximum Performance.
• Integrated Devices: VMware states “Disable from within the BIOS any unneeded devices, such as serial and USB ports.” These devices can be turned off under the “Integrated Devices” screen within the Dell BIOS.
• C1E: VMware recommends disabling the C1E halt state for multi-threaded, I/O latency sensitive workloads. This option is Enabled by default, and may be set to Disabled under the “Processor Settings” screen of the Dell BIOS. (I will keep the default to Enabled as I want to save more power in my data center and be enviornmental friendly)
• Processor Prefetchers: Certain processor architectures may have additional options under the “Processor Settings” screen, such as Hardware Prefetcher, Adjacent Cache Line Prefetch, DCU Streamer Prefetcher, Data Reuse, DRAM Prefetcher, etc. The default settings for these options is Enabled, and in general, Dell does not recommend disabling them, as they typically improve performance. However, for very random, memory-intensive workloads, you can try disabling these settings to evaluate whether that may increase performance of your virtualized workloads.

Finally, in order to take the advantage of ESX 4.1 Power Management feature in vCenter to show up, you need to change the setting in BIOS Power Management to “OS Control”.

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By admin, March 2, 2011 12:36 pm

As usual, I would suggest to wait another 1-2 months before upgrading your EQL firmware since the latest firmware may always contain bugs.

Since none of the followings applies to my enviornment, so I will just skip this update completely.

Issues Corrected in this version (v5.0.4) are described below:

• Contention for internal resources could cause a controller failover to occur.

• In rare circumstances, after a communication problem between group members, a PS6000, PS6500, PS6010, or PS6510 member may become unresponsive or experience a controller failover.

• In some cases, a controller failover may occur during a drive firmware update that takes place while the array is in a period of low activity.

• Drives may be incorrectly marked as failed. (happened mostly in PS4000 series)

• An invalid authentication failure may occur when using a RADIUS

• A hardware failure on the primary controller during a firmware update may inhibit failover to the secondary controller. server for CHAP authentication.

• Out-of-order network packets received by the array may cause retransmits.

• The array may not be able to clone a snapshot if the following scenario occurs: the parent volume was replicated to another group, the remote copy was promoted, and the changes were subsequently copied back to the original group using the Fast Failback process.

• Cannot clone snapshots of volumes with replicas that were promoted and subsequently failed back.

• Replication sometimes cannot be completed due to a problem with communication between the replication partners.

• In some cases, replication of a large amount of data may cause a shortage of internal resources, causing the GUI to become unresponsive.

• A network error may cause a failback operation to be unable to complete successfully, with the system issuing a “Replication partner cannot be reached” error.

• Exhausting the delegated space during replication may require that the in-process replica be cancelled in order to permit the volume to continue replicating as expected.

• A group running V5.0 firmware might be unable to perform management functions due to a lack of resources if a group running V3.3 firmware is replicating data to it.

• A restart of an internal management process could result in drives temporarily going offline in PS6010 and PS6510 systems.

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By admin, February 26, 2011 9:35 pm

I’ve encountered a problem when installing Windows Server 2008 R2 SP1 today and found the reason and solution pretty easy. It was due to Veeam B&R v5.0 automatically Disabled automount for SAN mode and W2K8 R2 SP1 requires automount to be enabled.

Solution:

1. Disconnect all active iSCSI connections and REMOVE the Target Portal from iSCSI favourite tab. 

2. From command prompt, issue the followings:
> diskpart
> automount enable

3. Reboot the server then go ahead and upgrade your W2K8 R2 with SP1, it will take about 50 minutes to complete, yes, it did take that long even on latest powerful server.

4. Then issue the following AFTER reboot:
> diskpart
> automount disable

5. Reboot the last time and then re-establish all previous iSCSI connections as usual.

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By admin, February 23, 2011 6:23 pm

規則1:跟人決定前途

民初名妓小鳳仙，要是找個民工，掃黃就被掃走了；
她找蔡鍔，就流芳千古；
要是跟孫中山，那就是國母。
所以不在于你干什么，而在于你跟誰干。

規則2：時間決定性質

趙四小姐16歲去大帥府，去1年，是奸情；
去3年，是偷情； 一去30年，那就是千古愛情。
很多事情不是不做，而是要看做多久。

規則3：關鍵崗位要有自己人

男子去提親，女方家長：請自我介紹。
A說：我有1000万；
B說：我有一棟豪宅，价值2000万；
家長很滿意。就問C，你家有什么？
C答：我什么都沒有，只有一個孩子，在你女儿肚子里。
AB無語，走了。
這個案例告訴我們一個淺顯的道理，
核心競爭力不是錢和房子，是在關鍵的崗位有自已的人。

規則4:做人要有屏功

女秘書神色凝重地說：王總,我怀孕了。
王繼續低頭看文件,然后淡淡一笑:我早結扎了。
女秘書楞了一會媚笑道:我是和您開玩笑呢!
王抬起頭看了她一眼，喝了口茶說:我也是。
這個案例告訴我們, 在江湖上晃的人,遇事不要慌,先讓子彈飛一會!