Archive for the ‘Storage’ Category

Expectations with new generation of DMX Technology

February 26th, 2009 No comments

There has been a big chatter about the next generation of EMC machines. After the initial release of DMX-3’s in 2005 and then the DMX-4’s in 2007, next generation DMX is almost due now.

With latest announcements from NetApp, IBM and EMC (Next Generation Celerra) in early Feb 2009, EMC’s DMX announcement might come right around EMC World 2009, plus or minus a month.

With the absence of Barry Burke from the Storage Blogosphere community over the past 3 months, it seems like he is busy working on strategy for the new generation of DMX machines.

Here is my wish list or expectations on the new DMX Platform.

Strategy, Cost, Marketing, Support…….

Do less with more!!!! This will have to be the reality of the new generation of DMX’s. In this tough economy and financial distress, if a new product is pitched with same efficiencies and overall similar ROI and TCO models, it will be hard to sell.

Some important CIO, CFO pitches would include, less foot print with more data, higher efficiency, delivered at 2/3rd the cost of previous generation of machines, energy savings, etc. Key Differentiators would be the cost per TB of data storage, cost per TB of management (Storage Administrators, OpEx), a savings of 20 to 30% in this equation might come into play.

The cost of warranty of each DMX is pretty high, during the warranty phase EMC Support Labs in Hopkinton, Sydney, Cork and Bangalore are supporting these boxes on a 24 x 7 basis. If EMC can manage to bring down the cost of in warranty repair including labor, parts, labs, engineering support, the savings from all these can be passed on to the customer. In this market, EMC might offer an extension of a 3 year warranty to a 4 year warranty that might help with ROI and TCO models.


Support for new generation DMX’s installs extended to ASN Partners.

Some portions of Enterprise channels will be designed to work like Commercial channels promoting premier partners and ASN partners to perform some work on the enterprise machines.

Model Numbers……

The million dollar question, will it be called Symmetrix DMX-5?

Or will it be called
DMX-5-XP (Extra Performance),
DMX-5-EF (EFD optimized machine),
DMX-5-V (extended support for Virtualization),
DMX-5-950 (same naming convention as before),
DMX-5-8 (8GB I/O),
DMX-V (You can think its V for virtualization or V for roman letter 5)

Let’s not get hung up on the model numbers though.


Will EMC for the first time drop the name Symmetrix from this generation of machines, this name comes from the Moshe days.


EMC is known to make a big bang with technology with all its new product releases and has been a leader in bringing new technology to the market. Let’s talk about a few technological aspects to look forward to in the new generation of DMX.

The underlying DMX-3 design has been different than the DMX and DMX2 generation of machines. The DMX-4 design has been prett
y similar to the DMX-3’s.

The point I am trying to make, EMC had a time frame of 5 years since the DMX2’s to come up with a radically changed DMX-5 design. Will a completely new design come to fruition with this generation of machines?

Enginuity Code……

A new Family Code is possibly due with this generation of DMX. May be an Initial release level of 5874.xx.xx.

Continued NDU (Non Disruptive Upgrade) Everything concept.

Introduction of PaPS (Plug and Play Support) with disk.


2 Cabinet: where one Cabinet is for Controllers, and the other for 2.5 inch Flash Disk. This model will be optimized for Flash Drives only and will be lighting fast.

2 or more Cabinets where the 1st Cabinet is for Controllers and the other ones for drives, the additional drive cabinets can be used for 3.5 inch drives or for 2.5 inch drives depending on the cabinet type you purchase. Also supported with Flash Drives.

Total Raw Storage……..

2048 TB (Double the capacity from DMX-4)


1024 GB Cache (First Enterprise Storage Array to hit 1TB of Cache)

Maximum usable memory: 512GB


Each DAF, GbE, FICON, ESCON controllers might be subdivided into 8 slices (ports, processors) creating further condensation of controllers, I/O, footprint, drives per DAF.

Additional backend ports will be added with this.

Each processor might be 2.4 Ghz PowerPC Chip.

Introduction of Clariion Type Concepts in Enterprise Storage…….

Plug and Play for disk replacements, where presence of an EMC CE onsite might not be required. This is pretty common with Clariion and NetApp Systems today.

Conceptual change of Global Memory to Local Memory, where memory is part of the controllers and not a global memory pool and Flash drives are used for certain memory operations as a vault.

Microcode upgrades being performed by the customer like its done for the Flarecode today.

EFD’s…….. b>

After support for 73GB and 146GB Flash, will might see 200GB , 400GB and 500GB disk on this new generation of machines?

With the use of EFD’s in Enterprise storage would the concept of IOPS with Storage change to GHz & MIPS.

Introduction of 2.5 inch drives…….

With some OEMs introducing support for 2.5 inch drives, we might see EMC moving in the same direction.

The next generation Clariion’s might have similar drives in them too.


Today the Symapi database resides on the Service Processor. Service Processors die; crash or get interrupted in middle of a change (provisioning, allocation, and configuration) and all of sudden the customer finds themselves in middle of crisis. All the change windows scheduled will have to be rescheduled, PSE’s dialing into the boxes to troubleshoot and fix issues, etc.

Introduction of an IP based (ethernet) connection to the DMX (talking about the DMX and not the SP) with multiple paths of communication. The SYMAPI databases will be locally stored on the DMX rather than the SP. This is similar to the VCMDB and the SFS volumes which already reside on the DMX.

Introduction of VMware ESXi into the Service Processor Environment to run multiple instances of SP Software and Windows for diagnostics, remote call home, etc. May be One VMware install can call home on the highest priority errors to location 1 and the second calling home with low to medium errors at location 2 and create two different queues for support priority.


As mentioned earlier, an introduction of IP based Ethernet management port, allowing SMC (Symmetrix Management Console) to interface, ECC and other Components can communicate through the same infrastructure.


Channel support which would include FICON, ESCON, GbE, FC, iSCSI, RF and some initial support for FCoE.

2048TB of storage in 5 cabinets can only be achieved with 2.5 inch drives.

Introduction of LP SATA Drives…..

Introduction of Low Power SATA Drives to conserve energy.

Plug and Play Support……

It sounds unreasonable, but if this can be incorporated into the DMX Platform, it will really take the overall platform to new levels with configuration, provisioning, customer interface, management, etc. Imagine if you want to add new drives to your current DMX, no BIN file change, just plug the drives in and configure through SMC.

High Efficiency….

At least 30% increase in efficiency, usage, savings, power and reduction in administration, management, support.

Added interface friendliness for SMC usage.

I/O Improvements……

8GB I/O per second Backend?

Improved Cache Partitioning , Mirroring and Priority Controls……

Further enhancements related to cache partitioning and cache mirroring, allowing customers to prioritize cache based on applications, times of the day, etc to certain set of drives or interfaces.

New Conceptual Design with BCV’s, DRV’s, Snaps and Clones……

As I say conceptual, I am not sure if history can change with this new generation of DMX machines or the new code. The mirrors, bcv’s, drv’s, snaps, clones are all treated as mirrored positions, configuration like RAID-5, RAID-6 is hard to manage.

If the code has been completely rewritten using new technologies this might be a reality, working more at a lun level rather than drive levels.

EFD’s and Optimizer…….

With EFD’s the use of Symm Optimizer is not deemed necessary, will optimizer become history?

Policy based support for Atmos…….

This will be one of the best features to look forward with the release of new DMX’s. Will DMX have native support for Atmos or will it be through a policy based engine as additional physical hardware.

Enhanced Support for VMware……..

This is a given, limitations with DMX and VMware with usage of LUN #’s, with the new DMX we will see additional native support for VMware integration features.

Enhanced RSA Integration…..

A lot was seen with DMX-3 and DMX-4 with access controls, etc. Further enhancements to security aspects of the storage.

Enhanced Support for RAID 5 / RAID 6, possible modification of one of the RAID designs to make the product faster………

Introduction of a new RAID type with this generation of DMX’s to compete with NetApp’s RAID-DP.

Storage Virtualization…….

This is really questionable, not sure where EMC wants to take Storage Virtualization.

Virtual Provisioning licensing…….

Virtual Provisioning included as part of the microcode and at no additional cost.

Native support for Deduplication?

Could this happen with the latest DMX’s

Built in SRM tools?

Some support for build in SRM tools into SMC, will help customers identify issues with the DMX.

Advancements with Green Infrastructure……..

This is a given, big marketing pitch, energy savings of 30% at least.

Advancements in Workflow and Automation…….

Further advancements with Workflow, Automation in new versions of ECC and SMC.

Initial Support for FCoE…..

Initial FCoE support has been released on the Clariions. We will see some initial support for FCoE on the new DMX generation.

EMC has discussed this topic so many different ways in the blogosphere, I am pretty sure we will see some early adaption of it in this generation of DMX’s.

Hope I did cover a lot of ground in terms of new technology that we can look forward from EMC.

As usual comments always welcome.

Next Generation Celerra – Unified Storage with Deduplication – Feb 2009

February 23rd, 2009 No comments

After NetApp’s recent (February 2009) announcement of V-Series SSD support and IBM’s (February 2009) announcement of DS8000, EMC is on the roll next with the announcement of its Next Generation NAS product Celerra.

As usual, expected from EMC, the Big Bang!!!!!

So after a lot of speculation, finally the Next Generation Celerra is released now. Again this time around, EMC is pushing the technology towards unified storage, deduplication and virtual provisioning giving away some bells and whistles at no cost.


Here are the highlights of the product.


Celerra Next Generation Ultra Scale Architecture, Unified Storage with Deduplication, Virtual Provisioning, File Level Retention, Support for Flash Drives – 30X IOPS, LP SATA Drives 5.4K, 32% Energy Savings, 22% lower TCO, 960 drives, 960TB of RAW Storage.


Release date: 23rd Feb 2009


Product availability: Feb 2009, the NS-8G and NS-960 might be available early March 2009.


Models: NS-120, NS-480, NS-960, NS-G8 (Gateway Version).


Introduction of LP Sata Drives: Low Power SATA Drives 5.4K RPMs.


Introduction of Flash Drives in Celerra: 30X IOPS, introduction of Tier 0.


Cost: Low CapEx, OpEx. Customer installation available with Low and Medium profile celerra’s. High End Celerra’s available to install through ASN Partners or by EMC.


Protocols Supported: NAS, MPFS, FC, iSCSI


Software: Deduplication (no cost), Virtual Provisioning (no cost), Startup Assistant (no cost), Celerra Manager (no cost), Volume Manager (no cost), Celerra Snapsure (no cost) –


Energy Efficiency: 32% less energy consumption


Lower TCO: 22%


Build on: Intel Xeon Chips


Choice of Delivery: File Based or Block Based, NAS to MPFS for throughput, iSCSI to FC for throughput



Supports 120 Drives

Supports Flash Drives

1 or 2 Blades





Support 480 Drives

Support Flash Drives

2 or 4 Blades





Support 960 Drives

Support Flash Drives

2 to 8 Blades





Supports 4 Arrays behind NS-G8

2 to 8 Blades



Applications usable on Celerra: VMware, Oracle, MS Exchange, MS SQL Server, Windows, Linux File Server


Celerra Integration Available: With VMware, Oracle, MS Exchange, MS SQL



High End: NS-G8, NS-960

Mid-Tier: NS-40G, NS-480, NS-120

Low End: NX-4


Compliance: Meets file level compliance related to SEC Rule 17a-4(f). Also available for the Celerra is 3rd Party Compliance.


Celerra File Level Retention: Celerra is being pushed to allow Filesystem archiving. For Application and Filesystem archiving you will still need a Centera.


ROI Models: Better ROI on Celerra models than any comparative NetApp  models.

Above are the product highlights, a technical blog on this coming soon……

Haven’t had a chance to play with it yet, but hopefully soon and looking forward to it. 

Edit: Read Dave Graham’s Blog Post on Celerra Here……

SUN StorageTek’s RAID 6 Implementation

February 16th, 2009 No comments

Continuing the series on RAID 6 technology with different OEM products; this time around it’s SUN StorageTek version of RAID 6 implementation on 6xxx series arrays.

Here are the links to previous posts related to RAID 6. It covers NetApp’s RAID-DP, Hitachi’s RAID 6, HP’s RAID 6 and technical post on various different RAID technologies.


NetApp’s RAID–DP

Hitachi’s (HDS) RAID 6

Different RAID Technologies (Detailed)

Different RAID Types

SUN’s Business Case

Similar to HP, Sun is not making a claim on performance with RAID 6; its only claim with this technology implementation on its products is Improved Reliability.

RAID 6 is supported on SUN StorageTek’s 6140, 6580 and 6780 Arrays

SUN StorageTek products traditionally support RAID 0, RAID 1, RAID 3, RAID 5, RAID 1+0 and now RAID 6.

Different Applications that can use RAID 6 technology on SUN StorageTek arrays are Exchange Email, Web Servers, File Servers, Oracle, SAP, SQL and MySQL.


Here is a small abstract about RAID 6 Technology as discussed in my earlier post.

Technology: Striping Data with Double Parity, Independent Data Disk with Double Parity

Performance: Medium

Overhead: 10% to 50% overhead, with additional drives you can bring down the overhead.

Data Loss: With one drive failure and two drive failures in the same Raid Group no data loss.

Advantages: RAID 6 is essentially an extension of RAID 5 which allows for additional fault tolerance by using a second independent distributed parity scheme (two-dimensional parity). Data is striped on a block level across a set of drives, just like in RAID 5, and a second set of parity is calculated and written across all the drives; RAID 6 provides for an extremely high data fault tolerance and can sustain multiple simultaneous drive failures which typically makes it a perfect solution for mission critical applications.

Disadvantages: Poor Write performance in addition to requiring N+2 drives to implement because of P+Q parity scheme.

The technology (P+Q Parity Algorithm) of Sun’s implementation and HP’s implementation of RAID 6 is similar. To further read about HP’s RAID 6, please use the link below.


The formula to calculate your usable space with RAID 6 is C * (n – 2), where C is the Size of your smallest drive in the RAID Group and n = number of drives. It is highly recommended all your disk drive sizes are similar.

The largest configuration of RAID 6 can be 257 drives with 2 parity drives and 255 data drives. Usage of more drives will help bring down the RAID 6 overhead since 2 drives are always allocated as parity.

This technology can be implemented with a minimum of 4 drives. The overhead with use of 4 drives in a single RAID Group is 50%. If you run 60 drives in a single RAID group, your overhead might be close to 4% {100 – [100 x 2 (parity) / 60 (drives)]}.

Lower write performance is a unique disadvantage of using RAID 6.

Both Sun StorageTek’s RAID 6 and HP’s RAID 6 offers advantages related to reliability and data protection but no additional benefits with performance, capacity, efficiency, speed, etc.

We will leave it up to the user to decide what RAID technology best fits their environment on SUN StorageTek 6XXX arrays for various different applications.

HP’s RAID 6 (ADG – Advanced Data Guarding)

February 13th, 2009 No comments

Continuing my RAID 6 posts, first HDS’s RAID 6, then NetApp’s RAID-DP and now this time around it’s HP’s RAID-6 ADG.

Some upcoming post would include RAID 6 Technology and its implementation by SUN, IBM and EMC. The final post should be about a comparison of all OEM products and the usage of RAID 6.

Here are the links to previous post related to RAID 6 and data protection

NetApp’s RAID–DP

Hitachi’s (HDS) RAID 6

Different RAID Technologies (Detailed)

Different RAID Types

Will try to keep this post short in terms of overall RAID 6 concepts, rather jump directly into the technical aspects of HP’s RAID-6 ADG (Advanced Data Guarding).

HP’s Business Case with RAID-6 Advanced Data Guarding (ADG)

So Advanced Data Guarding….the name is just perfect…. HP’s pitch to their potential storage customers would include a slide on ADG (I am a
ssuming that is the case).
This cost effective and fault tolerant technology is proprietary to HP and its patented, just cannot find a reference about it on the US PTO’s website.

RAID-6 ADG is supported on the MSA (Modular Smart Arrays) SAN platform.

I believe it’s not supported on any EVA (Enterprise Virtual Array) platforms. No RAID 6 support available on LeftHand Network SAN’s.

With HP XP-24000, HP XP-20000, HP XP-12000 and HP-XP 10000 there is no support for RAID-6 ADG, but there is native support for RAID 6 (dual parity).

HP Storage Products traditionally have support for RAID 0, RAID 1, RAID 1+0, RAID 5 and now RAID-6 ADG. Some LeftHand Network SAN’s support RAID 3 and RAID 4.

The argument from HP is pretty similar to the ones we already discussed with HDS and NetApp in the previous post. The push for RAID 6 at HP comes due to the existence of larger disk size and requirements for fault tolerance to run 24 x 7 x 365 applications.

Since there is an additional parity calculation associated with RAID-6, HP’s recommendation is to use RAID-6 ADG with lower writes and high reads only. If you have an application performing random writes, RAID 6 (ADG) might not be an option for you.

HP’s RAID-6 Advanced Data Guarding (ADG) Technology

Here is a snapshot of how this technology operates.

In the case here, we have 6 disk drives attached on a fiber loop or SCSI bus / controller. Data is striped on Disk 1, Disk 2, Disk 3, Disk 4 and then Parity (P1) and (Q1) are generated and written on Disk 5 and Disk 6. You can assume each data block is 4kb or 8kb in size.

Similarly, as the process continues, the next set of data strips start at Disk 1 then go to Disk 2, Disk 3 and Disk 6, while the parity is written on Disk 4 (P) and Disk 5 (Q). ADG is based on P + Q algorithm to calculate two independent parity sets. Exclusive OR (XOR) is used to calculate the P and Q Parity. The P Parity is exactly like it would be for RAID 5 and Q is calculated based on Error Correcting Code. The Q is then striped across all the disk within the RAID Group.

If a single drive is lost in the Raid Group, data is rebuild using ordinary XOR P (Parity). Also the P and Q are both recalculated for each rebuild block. If a second drive fails during this time, the rebuild takes place using the Q Parity. During these times data is still completely available with a little degradation.

If you do add a spare drive to this configuration, now your raid group can pretty much withstand 3 drive failures before data loss.

This technology can be implemented with a minimum of 4 drives. The overhead with use of 4 drives in a single RAID Group is 50%. If you run 60 drives in a single RAID group, your overhead might be close to 4% {100 – [100 x 2 (parity) / 60 (drives)]}.

The formula to calculate your usable space will be C * (n – 2), where C is the Size of your smallest drive in the RAID Group and n = number of drives. It is highly recommended all your disk drive sizes are similar.

If you are running more than 14 physical drives in a single RAID Group, HP’s recommendation is to use RAID-6 ADG. With 6 drives in a RAID Group, the failure probability is 1E-10. With 60 drives in a RAID Group, the failure probability is 1E-7.

Again HP’s big pitch with RAID-6 ADG is Cost Effectiveness with Fault Tolerance, not really performance.