Comments (0)

By admin, May 22, 2012 5:38 pm

I was told Power Connect 52xx/54xx series switches are optimized for VoIP and they are no longer recommended by Equallogic as 50% of the available buffers are reserved for VoIP unless you change the setting and REBOOT the switch.

I haven’t tried the following VoIP setting recommended by EQL as I don’t want to mess around my optimized configuration file.

Besides, I think there is an alternative way which I’ve completely disabled VoIP setting using PowerConnect 5448 GUI. There is a check for you to disable VoIP in the Switch session under the GUI.

Go to each switch and do the following:

Put the switch into admin and configuration mode.

enable
configure

Disable/remove iSCSI and VoIP optimization

voice vlan oui-table remove 00036b
voice vlan oui-table remove 00096e
voice vlan oui-table remove 0001e3
voice vlan oui-table remove 000fe2
voice vlan oui-table remove 0060b9
voice vlan oui-table remove 00d01e
voice vlan oui-table remove 00e075
voice vlan oui-table remove 00e0bb

Exit from configuration mode

exit

Save the configuration

copy running-config startup-config

When ready, type ‘reload’ to reboot

reload

Comments (5)

By admin, April 28, 2012 12:04 pm

This latest brief review compared the pros and cons of the leading backup vendors for VMware ESX. (In Chinese).

It only touched the surface, not technical oriented and in fact not detail at all, sounds more like a marketing material to me.

Comments (0)

By admin, April 27, 2012 11:20 am

VMware ESX source code has been stolen and posted online, but the company said its virtualization platform doesn’t necessarily pose an increased risk to customers.

The stolen code amounts to a single file from sometime around 2003 or 2004, the company said in a blog post.

“The fact that the source code may have been publicly shared does not necessarily mean that there is any increased risk to VMware customers,” according to the blog written by Iain Mulholland, director of the company’s Security Response Center.

The code was stolen from a Chinese company called China Electronics Import & Export Corporation (CEIEC) during a March breach, according to a posting on the Kaspersky Threat Post blog.

The code along with internal VMware emails were posted online three days ago.

VMware didn’t respond immediately to a request for more information about the impact of the breach on customers.

Eric Chiu, president of virtualization security firm Hytrust, said it’s hard to say what VMware customers should do because there’s not enough detail about how the exposed code is being used in current products.

In general, though, customers should review the security for virtual environments to address the fact that a compromised hypervisor exposes multiple virtual machines.

While the incident is reminiscent of the breach last year of RSA source code, the circumstances differ. An RSA partner was breached and that breach was used to send a malware-laced email to an RSA staffer who opened it.

In VMware’s case, the CEIEC network was hacked and finding the source code was fortuitous.

This is what VMware posted in a blog: “Yesterday, April 23, 2012, our security team became aware of the public posting of a single file from the VMware ESX source code and the possibility that more files may be posted in the future. The posted code and associated commentary dates to the 2003 to 2004 timeframe.

“The fact that the source code may have been publicly shared does not necessarily mean that there is any increased risk to VMware customers. VMware proactively shares its source code and interfaces with other industry participants to enable the broad virtualization ecosystem today. We take customer security seriously and have engaged internal and external resources, including our VMware Security Response Center, to thoroughly investigate. We will continue to provide updates to the VMware community if and when additional information is available.”

Network World (US)

Comments (9)

By admin, April 13, 2012 10:42 am

Latest 12th generation Poweredge servers offers Express Flash PCIe SSD based solution for extreme high IOPS application. Available in Q2, 2012, now you can plug a total of four PCIe SSDs to the front of R720 (PCIe doesn’t support R720xd) and the PCIe SSDs are connected to the server board PCIe 2.0 directly. There is a cable directly connect to the on board  PCIe from the backplane of the PCIe SSD tray as shown in H710p manual, more information can be found in PowerEdge R720/R720xd Technical Guide.

Btw, the only features difference between H710p and H710 are H710p has 1GB cache and supports CacheCade and FastPath where as H710 only has 512MB cache and does not support CC and FP.

This is the same case as in Poweredge R710 H700 raid card, CacheCade and FastPath are only supported with 1GB NV Cache version.

SEQUENTIAL I/O (not RANDOM) bandwidth is no longer limited by Perc Raid Card as the PCIe SSD becomes a system device now. This means you got to have a corresponding driver for the installed OS underneath, I checked VMware is on the list. Hey, doesn’t this sound exactly the same as Fusion-IO?

The maximum bandwidth is up to 2GB/s for PCIe 2.0, 1.8GB/s for Read and 1.2GB/s for write as advertised by Dell for a single PCIe SSD. Well one thing I really don’t understand is, why Dell does not use the latest PCIe 3.0 connector which offers much higher bandwidth (3.2GB/s), it’s definitely strange!

In contrast, I can reach 1.3GB/s for Read and 1.2GB/s for Write (note both are sequential) as well using a consumer grade MLC based SSD (Crucial M4 128GB) through Perc H700 (that’s PCIe 2.0) on R710 anyway. Also for Random IOPS, I can reach 55,000 IOPS easily as advertised by Crucial, so what’s the point using PCIe SSD after all?

After reading the white paper Optimizing SQL Server Storage Performance with the PowerEdge R720, I figured out these new PCIe based SSDs (175GB and 350GB) are much more reliable now with SLC NAND (I smell $$$) and they required Perc H710P (I thought it’s not using the raid card anymore). In additional, One PCIe SDD drive resulted in 10.5x more IOPS (note Random) than 16 HDDs 10K array, that simply means a single PCIe SSD is equivalent to 10.5 PS6000X or 168 10K RPM spindles, excellent, but sounds unreal to me. I couldn’t find 107,518 IOPS is based on 4k or 32k, if it’s 4k, my consumer grade Crucial M4 128GB is definitely a much cost effective solution, probably at only 1/30 the cost.

Also remember SSD performance will degrade over time due to excessive write cycle and if you stress test it over a very long period of time continuously (that’s over 24 hours), the IOPS will drop to 1/10 of it’s starting value. However a SAS 15K RPM raid EQL box will sustain all the way. (Please correct me if I’m  wrong)

Finally, something related, the SSD Dell used in their latest Equallogic is Pliant based SSD (e-MLC NAND as well), but those are 400GB.

Micron Announces 2.5″ PCIe SSD for Enterprise

Micron has announced the first 2.5″ SSD which utilizes PCIe interface instead of the more common SATA interface. The 2.5″ form factor allows for easy serviceability because the drives can be placed into the front end of servers. Traditional PCIe cards are harder to service and are not hot-swappable, requiring the server to be powered down. Furthermore, using PCIe instead of SATA eliminates the bandwidth bottleneck that SATA produces, maximum of 6Gb/s (or 750MB/s) versus 32Gb/s (or 4GB/s) for PCIe 2.0 x8.

The drive is essentially a 2.5″ version of Micron’s P320h SSD, which Micron announced in June last year. Both use 34nm SLC NAND and are based on the same in-house controller. According to Micron’s specifications, the controller is actually one of the fastest to date – providing read speeds of up to 3GB/s and write speeds of up to 2GB/s (yes, with a big B, i.e. bytes). Random 4KB read performance maxes out at 750K IOPS, while random read tops out at 341K IOPS (700GB version).

However, keep in mind that the controller features 32 channels. 2.5″ SSDs typically utilize 16 NAND packages, which means only half of the available channels would be in use with Micron’s controller. Micron couldn’t provide us with any detailed specifications or performance figures yet as this announcement was for promoting the new interface, not the actual drive, so we don’t know how much the performance differs from the FHHL sized PCIe card. The capacities are a bit smaller at 175GB and 350GB and at least random write performance should be slightly lower than what the FHHL card offers, but it’s certain that this will be one of the fastest (if not the fastest) 2.5″ SSDs.

Micron is currently sampling interested customers and an actual product announcement is going to follow later this year with more specific performance details. No pricing has been revealed, but Micron hinted that the price of the FHHL card would be over $16 per GB, which works out to be $2800 for 175GB and $5600 for 350GB if the 2.5″ version is priced similarly.

Update April 13, 2012

英特爾週四（4/12）推出910系列固態硬碟（SSD）產品，具備400GB和800GB兩種容量，並支援PCIe技術，可適用於雲端運算、虛擬化和線上交易等資料中心的儲存需求。

新產品採用最佳化的多層單元（MLC） 25奈米快閃記憶體，可提供5年內每天10次完整的硬碟寫入，與前一代標準型MCL快閃記憶體產品相比，耐用性提升了30倍。

英特爾表示，910系列具備高效能、耐久和可靠等特性，是用來取代I/O密集硬碟的理想選擇。它容易安裝，且無需修改既有的伺服器設計，可適用於儲存需要高效能處理和存取的分層和快取檔案。一顆910 SSD可取代多顆15K RPM的硬碟，不僅能節省空間和功耗，還能提升儲存擴充性，並同時降低時間延遲。

這是英特爾900系列產品的擴展，首度推出支援PCIe技術的SSD。800GB容量產品的速度為2GB/s持續序列讀取和1GB/s序列寫入，以及180,000 4K 隨機讀取IOPS（每秒輸入輸出運作）和75,000 4K隨機寫入IOPS。

樣品現已開始提供，量產時程訂於今年中。400GB容量價格為1929美元，800GB為3859美元，均提供五年保固。

Comments (0)

By admin, April 13, 2012 10:35 am

No wonder most of the data centers in Hong Kong had such problem yesterday morning, GFW again, yuck!

Yesterday is kind of strange, ping to Hong Kong IP remains as low as 9-15ms, but non of the TCP ports can be opened, including VPN or SSL, not even regular port 80.

I think it’s probably due to the recent power struggle in Mainland causing the Internet censorship to be upgraded at China Telecom’s backbone network.

Some mainland Internet users reported that they couldn’t access overseas Websites such as CNN and MSN as usual with tools that help get over the Great Firewall since 10:40am Thursday.

According to a Google+ post, a user suspected that the glitch was caused by various service providers’ recent firewall upgrade or a problem in China Telecom’s backbone network.

The glitch has gone reportedly after noon. None of the mainland ISPs has offered explanations or statements on the problem by far.

Comments (4)

By admin, April 12, 2012 10:13 pm

Say if I have ordered the latest Dell Powerdge R720xd with 2 sockets Xeon-E5 CPUs and fill it up with 768GB Ram (32GB x 24 Dimms). R720 supports 4 memory channels per processor, that’s 3 dimms per channel, so 12 dimms in total per processor, or 24 dimms per 2 sockets. In contrast, R710 supports 3 memory channels and 3 dimms per channel, a total of 18 dimms per 2 sockets.

Since vSphere 5.0 Enterprise Plus Licensing Model allows 96GB vRAM per socket, so that’s 192GB vRAM per the above configuration, this leaves the remaining 576GB vRAM in question. According to their licensing formula, I need to purchase 6 more EP licenses in order to fully use the 768GB Ram. Sounds strange that I need to have 8 CPUs license while the physical server only has 2 CPUs.

Let’s put the above extreme case aside, in reality not many is going to order that super expensive 32GB and no one is going to put that much ram in mid-range server like R720 as well anyway.

So let’s focus on the optimal memory configuration for R720, I would say it’s most likely to be 192GB (in fact 256GB).

Currently, mainstream is still 8GB ram, therefore for 192GB RAM, that’s 24 Dimms (8GB x 24), but with 3 Dimms Per Channel (DPC) configuration, it will decrease the RAM speed to 1066Mhz which I want to maintain RDIMM at 1333Mhz bandwidth and 1.35V, so in order to do that, I can only use 16GB ram and for 192GB, that’s 12 Dimms, an uneven number configuration, 3 channels per side, missing one channel, this sounds REALLY ODD?!!! Isn’t it a big drop in memory performance if we do not fill up all channels on each socket? (I might be wrong on this)

So if I insist to run at 1333Mhz, the only choice I have is to have 2DPC x 4 channels, that’s 16 Dimms x 16GB = 256GB, well, it’s over 192GB limit!

I really don’t know what else I can configure the memory in order to fully use 256GB ram with 2 VMware EP license. If you have any better suggestion, please let me know. Of course, if my assumption of fully using all 4  channels proved to be wrong later, then this won’t be a problem.

That’s why people are suggesting VMware to raise the bar to 128GB per socket, this would be perfect solution then, let’s see.

Oh…I just noticed NASDAQ:VMW had a free fall on Wed as their CFO jumped off the ship, is something going on under the table?

Comments (0)

By admin, April 12, 2012 2:21 pm

There is a very good article about DDR3-1600 Memory Configuration for Poweredge 12th Generation Servers, it’s good to see finally the 1U R620 having 24 Dimms as their big brother 2U R720. Also, I found a link regarding the latest LRDIMM, it’s very interesting as well.

On the eve of Intel’s release of Sandy Bridge-EP, the next generation of Xeon processors for servers, the memory industry has geared up for another uptick in memory speed.  Following Moore’s law– speed and performance are increasing while costs for memory are at historic lows.   Configuring servers for maximum power and performance has never been more affordable.

By selecting the latest DDR3-1600 (PC3-12800) speed DIMMs that deliver a data rate of 12.8 GB/s, you will realize about 20% more throughput than existing DDR3-1333 (PC3-10600) speed memory which delivers a data rate of 10.66 GB/s.   PC3-10600 RDIMMs, the most commonly used RDIMMs in today’s Xeon 5600 CPUs based servers, will give way to the faster PC3-12800 speed memory.

Just an FYI for the novice reader—the terms “DDR3-1333” and “DDR3-1600” are DRAM speeds, and “PC3-10600” and “PC3-12800” are MODULE (DIMM) speeds, as defined by JEDEC.  However many times, the DRAM speed nomenclature is used universally as both DRAM and DIMM speed indications.

AMD also has adopted the faster DDR3-1600 speed memory for servers with the introduction of Opteron 6200 “Interlagos” CPUs.   Servers and workstations will see significant performance improvements over prior generation Opteron 6100, which also featured DDR3-1333 as the top memory speed.

This discussion is all about speed and performance–since these DDR3-1600 applications will be offered at standard DDR3 1.5V power only.

Low voltage 1.35V (PC3L), and future 1.25V lower voltage dimms, will not be enabled at DDR3-1600 speed in this new generation of servers.

They will however continue to support DDR3L-1333 (PC3L-10600R) memory speeds at low voltage (1.35V), for those wishing to extract maximum power savings from their server infrastructure in lieu of the highest possible performance.   The trade-off decisions continue between maximum power savings vs. maximum compute performance.   The “tug-of-war” between “Going Green” vs. “My Servers are my Strategic Weapons” groups continues, with the power users configuring for maximum speed and competitive advantage by delivering the fastest response times.

Additionally, a new 32GB DDR3-1333 (PC3L-10600) LRDIMM (Load Reduced DIMM) is available now which is required for these servers to achieve a maximum memory capacity of 768GB.

Comments (35)

By admin, April 11, 2012 10:48 pm

Around this time December last year, I’ve been searching for a reliable, cost effective SSD for vSphere ESX environment as the one from Dell is prohibitory expensive to implement.

Besides, Dell SSDs may have poor performance problem as someone described in VMTN, those 1st generation SSD either provided by Sumsung OEM (100GB and 200GB), or Pliant based (149GB) which is much faster than Sumsung ones and of course much more expensive (over priced that is) as well. Both are e-MLC NAND.

Anyway, I’ve finally purchased a Crucial M4 SSD 128GB 2.5″ SATA 3 6Gb/s (around USD200 with 3 years warranty), here is for a list of reasons.

Then my goal is to put this SSD to Dell Poweredge R710 2.5″ tray and see how amazing it’s going to be. I know it’s not a supported solution, but no harm to try.

The Perc H700/H800 Technical Book specifically states it supports 3Gb/s if it’s a SATA SSD, but I found out this is not true, read on.

1. First thing first, I have Upgraded Crucial firmware from 0009 to 0309 as in early Jan 2012, users found out Crucial M4 SSD has a 5200 Hours BSOD problem, it’s still better than Intel SSD’s 8MB huge bug.

Correct a condition where an incorrect response to a SMART counter will cause the m4 drive to become unresponsive after 5184 hours of Power-on time. The drive will recover after a power cycle, however, this failure will repeat once per hour after reaching this point. The condition will allow the end user to successfully update firmware, and poses no risk to user or system data stored on the drive.

Something more to notice that SandForce controller based SSD has a weakness that when more and more data is stored in SSD, it’s performance will decrease gradually. Crucial M4 is based on Marvell 88SS9174 controller and it doesn’t have this kind of problem. It is more stable and the speed is consistent even with 100% full in data.

In additional, Crucial M4 Garbage Collection runs automatically at the drive level when it is idle and it has Garbage Collection which works automatically in the background in the same way as TRIM independent of the running OS. As TRIM is an OS related command, so TRIM will not be used if there is no support in the OS (ie, VMware ESX).

2. The most difficult part is actually finding the 2.5″ tray for Poweredge R710 as Dell do not sell those separately, luckily I was able to get two of them off the auction site locally quite cheap and later found out they might be Counterfeit parts, but they worked 100% fine, only the color is a bit lighter than the original ones.

3. Then the next obvious thing is to insert the M4 SSD to R710 and hopefully Perc H700 will recognize this drive immediately. Unfortunately, the first run failed miserably with both drive indicator lights OFF, as if there is no drive in the 2.5″ tray.

Check the OpenManage log, found out the drive is not Certified by Dell (Huh?) and Blocked by Perc H700 right away.

Status: Non-Critical        2359        Mon Dec 5 18:37:24 2011        Storage Service        A non-Dell supplied disk drive has been detected: Physical Disk 1:7 Controller 0, Connector 1

Status: Non-Critical        2049        Mon Dec 5 18:38:00 2011        Storage Service        Physical disk  removed: Physical Disk 1:7 Controller 0, Connector 1

Status: Non-Critical        2131        Mon Dec 5 19:44:18 2011        Storage Service        The current firmware version 12.3.0-0032 is older than the required firmware version 12.10.1-0001 for a controller of model 0×1F17: Controller 0 (PERC H700 Integrated)

4. Then I found out the reason is older H700 firmware blocked the non Dell drive access, so I have to updated Perc H700 firmware to latest (v12.10.x) using USC again. Before the upgrade, I boot into H700’s ROM and found indeed the SSD drive is not presented in the dirve pool. Anyway, the whole process took about 15 minutes to complete, not bad.

5. After the server returns to normal, the Crucial M4 128GB SSD now has light showing in the tray indicator and working correctly partly, as the indicator on the top always blinking in amber (ie, orange),   “Not Certified by Dell” indicates in OpenManage log, and this caused the r710 front panel LCD also blinking in amber.

Besides, under Host Hardware Health in vCenter, there is one error message showing “Storage Drive 7: Drive Slot sensor for Storage, drive fault was asserted”

From Perc H700 log file:
Status: OK        2334        Mon Dec 5 19:44:38 2011        Storage Service        Controller event log:

Inserted: PD 07(e0xff/s7): Controller 0 (PERC H700 Integrated)
Status: Non-Critical        2335        Mon Dec 5 19:44:38 2011        Storage Service        Controller

event log: PD 07(e0xff/s7) is not a certified drive: Controller 0 (PERC H700 Integrated)

I clear the log in OpenManage turns the front panel LCD returns to blue, but SSD drive top indicator light still blinks in amber, don’t worry, it’s just indicator showing it’s a non-dell drive.

Later, this was confirmed by a message in VMTN as well.

The issue is that these drives do not have the Dell firmware on them to properly communicate with the Perc Controllers. The controllers are not getting the messages they are expecting from these drives and thus throws the error.

You really won’t get around this issue until Dell releases support for these drives and at this time there does not appear to be any move towards doing this.

I was able to clear all the logs under Server Administrator.  The individual lights on the drives still blink amber but the main bevel panel blue.  The bevel panel will go back to amber again after a reboot but clearing the logs will put it back to blue again.  Minor annoyance for great performance.

Update: If you have OM version 8.5.0 or above, now you can disable the not a certified drive warning completely! Strange that Dell finally listen to their customers after years of complain.

In C:\Program Files\Dell\SysMgt\sm\stsvc.ini update the parameter to NonDellCertifiedFlag=no

6. The next most important thing is to do a VMFS ReScan, ESX 4.1 found this SSD immediately Yeah! and I added it to the Storage section for testing.

Then I tested this SSD with IOMeter, Wow…man! This SINGLE little drive blows our PS6000XV (14 x 15K RPM RAID10) away, 7,140 IOPS for real life 100% random, 65% read test, almost TWICE than PS6000XV!!! ABSOLUTELY SHOCKING!!!

What does this mean is A Single M4 = 28 x 15K RPM RAID10, absolutely crazy numbers!

##################################################################################
TEST NAME——————-Av. Resp. Time ms——Av. IOs/sek——-Av. MB/sek——
##################################################################################

Max Throughput-100%Read……1.4239………39832.88………1244.78

Max Throughput-100%Write……1.4772………37766.44………1180.20

RealLife-60%Rand-65%Read……8.1674………7140.76………55.79

EXCEPTIONS: CPU Util. 93.96%, 94.08, 30.26%
################################################################

So why would I spend 1,000 times more when I can get the result with a single SSD drive for under USD200? (later proved I was wrong as if you sustain the I/O process, Equallogic will stay at 3,500 IOPS and SSD will drop to 1/10 of it’s starting value)

Oh…one final good thing is Crucial M4 SATA SSD is recognized as 6Gbps device in H700, as mentioned in the very first lines, according to Perc H700 tech book, it said H700 SSD SATA interface only supports up to 3Gbps, I don’t know if it’s the latest Perc H700 firmware or actually the M4 SSD itself somehow breaks that limit.

Let’s talk something more about Perc H700 itself, most people know Dell’s Raid controller cards are LSI Megaraid OEM since Poweredge 2550 (the fifth generation) and Dell Perc H700 shares many advanced feature with its LSI Megaraid ones.

Such as CacheCade, FastPath, SSD Guard, but ONLY available in the Perc H700 1GB Cache NV Ram version.

Optimum Controller Settings for CacheCade – SSD Caching
Write Policy: Write Back
IO Policy: Cached IO
Read Policy: No Read Ahead
Stripe Size: 64 KB

Cut-Through IO = Fast Path Cut-through IO (CTIO) is an IO accelerator for SSD arrays that boosts the throughput of devices connected to the PERCController. It is enabled through disabling the write-back cache (enable write-through cache) and disabling Read Ahead.

So this means you can use LSI Megaraid Storage Manager to control your Perc H700 or H800. In my case, I found my H700 does not support any of the above as it’s only a 512MB cache version. However “SSD Caching = Enable” shows in the controller property under LSI Megaraid Storage Manager and cannot be turned off as there is no such option, I am not sure what this is (definitely it’s not CacheCade), if you know what this is, please let me know.

Then let’s move into something deeper regarding Perc H700’s bandwidth as I found the card itself can reach almost 2GB/s, this is again too good to believe!

The PERC H700 Integrated card with two x4 internal mini-SAS ports supports the PCIe 2.0 x8 PCIe host interface on the riser.

PERC H700 is x8 PCIe 2.0 (bandwidth is 500MB/s per x1 lane) with TWO SAS 2.0 (6Gbps) Ports with x4 lane, so total bandwidth for EACH lane is 500MB/s x 4 = 2,000MB/s (ie, 2GB/s).

EACH SATA III or SAS 2.0 bandwidth is 6Gbps, this means EACH drive maximum speed can produce 750MB/s (if there is such SAS drive), so it will take about SIXTEEN (16) 6Gbps 15K rpm disks (each about 120MB/s) in reality to saturate ONE PERC H700’s 2GB/s theoretical bandwidth.

A single Crucial SSD M4 is able to go over 1GB/s in both Read and Write really shocked me!

This means two consumer grade Crucial SSD M4 in RAID0 should be enough to saturate Perc H700’s total 2GB/s bandwidth easily.

From ESX Storage Performance Chart, it also shows the consistent IOPS with IOMeter’s result. (ie, over 35,000 in Seq. Read/Write).

From Veeam Monitor, showing 1.28GB/s Read and 1.23GB Write

In fact, not just me, in reality, I found out many people were able to achieve this maximum 1,600MB or 1.6GB/s. (yes, theoretical is 2GB/s) with two or more SSD under Perc H700.

Of course the newer PCIe 3.0 standard is 1GB/s per x1 line, so a x4 will give you 4GB/s,a 200% increase, hopefully someone will do a benchmark on Poweredge R720 with its Perc H710 shortly.

Some will say using a single SSD is not safe, OK, then let’s make it a RAID1, if not RAID10 or RAID50 with 8 SSD drives, with the newer Poweredge R720, you can put maximum 14 SSD to create a RAID10/RAID50/RAID60 with 2 hot-spare in a 2U, more than enough right?

The most important is the COST IS MUCH MUCH LOWER when using consumer grade SSD and it’s not hard to imagine 14 SSD in RAID10 will produce some incredible IOPS, I guess something in 50,000 to 100,000 should be able to achieve without much problem. So why use those sky high $$$ Fusion IO PCI-e cards forks?

Finally, I also did a few desktop benchmark from within the VM.

Atto:

HD Tune:

Conclusion, for a low cost consumer SSD, 100% Random RealLife-60%Rand-65%Read with 32K transfer request size, 7,000+ IOPS is simply amazing!!!

Comments (0)

By admin, April 11, 2012 10:16 am

The incident of NWT data center in 2009. There was a sudden power surge  that broke the electric circuit and there supposed to be a diesel generator to provide the backup power, but guess what? There is not enough diesel fuel in the tank. Wow! This is so similar to SmarTone’s data center  down time and I am surprised that they don’t have auto real-time failover site, this is strange for a listed company with over a few millions of subscribers in Hong Kong, a big question to their so called Level 3 ISO approved data center.

Now the government suggested other carriers should temporary provide the 2G/3G service for any carrier facing downtime, I think it’s pure dreaming, why would they anyway?

I bet One2Fre is the most happy face this time to see SmarTone sinking, as SmarTone was not so nice to them either previously.

Dear SmarTone Customer,

As a valued customer, I would like to apologise to you for Monday’s service disruption and inform you of what actually happened, and what we have done to resume services and minimise disruption.

On 9 April at around 8:00 am, the building in which one of our three switching centres is located, suffered a total power failure disrupting the power supply to the entire building. Our switching centre’s standby battery system immediately substituted the failed power source and there was no disruption to service. Our backup generator then commenced operation, successfully taking over from the standby battery system.

At approximately 10:35am a component in the starter circuit board of the backup generator broke down unexpectedly, causing the generator to stop operating. This also caused a huge surge of electrical current that triggered circuit breakers to disconnect the cellular switching system from the standby battery system. The resulting power outage disrupted cellular service in several areas in Hong Kong and selected MTR stations in Kowloon.

Emergency restoration and recovery procedures started immediately and service was restored progressively from 12:15pm onwards. Aside from a small number of selected services, voice and mobile internet services were largely back to normal at 1:00pm. From 2:30pm onwards, all SMS services had returned to normal. The Company’s two remaining switching centres operated as normal during this incident.

We carry out inspections and tests of all power generation facilities regularly. The backup generator which caused the outage successfully passed recent inspections and tests on 22 February. We will submit an incident report to the Office of the Communications Authority and will re-evaluate our procedures for informing the public and its customers.

We regret the inconvenience caused to you and we will thoroughly investigate both the reasons for the building’s power outage and the failure of our power backup systems in order to ascertain the root cause. We are determined to learn from these findings and make improvements to prevent similar incidents in future.

Yours sincerely,

Douglas Li
CEO

Comments (0)

By admin, April 10, 2012 4:20 pm

Finally figured out what “Vertical Port Failover” is, that’s a cool feature to maintain the original full 4Gbps bandwidth! Is it really useful? To be honest, I don’t think so, well it’s fun to have though.

According to March 2012 Dell EqualLogic Configuration Guide v13.1 12:

In PS Series controllers prior to PS4100/6100 families, a link failure or a switch failure was not recognized as a failure mode by the controller. Thus a failure of a link or an entire switch would reduce bandwidth available from the array. Referring to Figure 5, assume that CM0 is the active controller. In vertical port failover, if CM0 senses a link drop on the local ETH0 port connection path, it will automatically begin using the ETH0 port on the backup controller (CM1). Vertical port failover is bi-directional. If CM1 is the active controller then vertical port failover will occur from CM1 ports to CM0 ports if necessary.

With PS4100/PS6100 family controllers, vertical port failover can ensure continuous full bandwidth is available from the array even if you have a link or switch failure. This is accomplished by combining corresponding physical ports in each controller (vertical pairs) into a single logical port from the point of view of the active controller. In a fully redundant SAN configuration, you must configure the connections as shown in Figure 20.

In a redundant switch SAN configuration, to optimize the system response in the event you have a vertical port failover you must split the vertical port pair connections between both SAN switches. The connection paths illustrated in Figure 6 and Figure 7 show how to alternate the port connection paths between the two controllers. Also note how IP addresses are assigned to vertical port pairs.