Posts Tagged ‘EMC’

EMC’s Unified Platform and Storage Tiering on GESTALTIT.COM

September 24th, 2009 No comments

Check out the new featured blog post on GestaltIT by myself and Ed Saipetch on EMC’s Unified Platform and Storage Tiering, where we talk about some important next generation features and products from EMC. Also discussion revolves around possibly the direction EMC is moving with their Unified Hardware – Software Platforms and Storage Tiering using next generation technologies like FAST.


The Blue lights on EMC Symmetrix V-Max Systems

September 10th, 2009 6 comments

If you were to walk in a Datacenter and see an EMC Symmetrix V-Max for the first time, you will end up giving it a look.

It’s those Blue Flashy lights in the front of the unit that just catches your eyes.

It gives the Symmetrix V-Max the Sleek and Sexy look..

Here are some pictures to prove that..


v-max image 2

v-max image

Visible in the picture below are Cisco UCS blades, NetApp systems, HP systems, Cisco Switches, Xsigo Systems, but you can surely spot the Symmetrix V-Max

vmworld 2009

EMC Symmetrix V-Max

A video from EMC World 2009

So these lights are USB powered through USB cables, a very simple idea though a genius one. Enterprise class arrays and the use of USB ports at the backend of these systems keep these Blue flashy lights on.

Here are the pictures of those USB connectors from the front. Believe it or not, they are redundant as well.

(Look at the USB cable connectors that go on the front door, 2 of them right above the blue light)


As Storage Anarchist says in his Blog post “The first thing you’ll probably notice about the new Symmetrix V-Max is the packaging – and specifically the glossy-black panel with the blazing blue LED light bar that underscores the name Symmetrix on every door. The design team had a lot of fun blending the modern gloss-black look of today’s popular personal communications devices with the image of stability and security that customers expect from Symmetrix.”

Yea that is right,,,,,,,,,, this post was about the Blue lights on the Symmetrix V-Max Systems :-)

Oh…the big question, will it call home through the EMC ESRS Gateway if one of these Blue lights fail?

The NetApp CEO Succession: Tom Georgens succeeds Dan Warmenhoven

August 20th, 2009 No comments

Another day for NetApp in the headlines, this afternoon the news hit the wire that the current CEO of NetApp (Dan Warmenhoven) is retiring and Tom Georgens will be taking his position. Dave Hitz’s blog post broke the news to the world at around 4:30 PM.

Dave quotes: “Today Dan Warmenhoven, our previous CEO, announced that Tom Georgens is our new CEO. Dan will continue as Chairman of the Board, and he will also have a new role, reporting to Tom, focusing on relationships with major partners. His title is Executive Chairman since he’s an executive of the company as well as a board member.”

I really like how Dave Hitz begins his blog; unfortunately the last year has been a losing battle for Dan Warmenhoven, though Dan had a great track record of bringing NetApp from 50 employees to 8000 employees during his tenure. Dan has been with NetApp since the very early days and though his succession Tom Georgens was identified several years ago, the timing of this move raises a lot of questions. NetApp also declared their quarterly numbers today, which sure indicated a profit growth for the past quarter.

Though it was fully expected that Dan Warmenhoven would retire, it remains to be seen if during his last days as CEO of NetApp whether he had any major differences with the board after the Data Domain battle. Tom Georgens comes with a wealth of information and has worked for companies like EMC, LSI Logic and has created some very strong partnerships with various players in the Data Storage industry, his immediate future direction may remain the same as Dan Warmenhoven. In a long run it still remains to be seen if Tom Georgens and his team would grow the NetApp business independently or stage NetApp to be purchased.

I still have doubts about Dan Warmenhoven retirement announcement at such a time crucial time when the company possibly went through rocky times, Dan’s the vision and leadership grew the business over 15 years to this level and then one afternoon decides to step down with any prior notice to the Storage – Wall Street Community, sounds a bit strange. Dan will still continue to be the Executive Chairman of the board, but we should see his role fade slowly but surely over the next 6 months.

We wish Tom Georgens Goodluck & Success in this new position.

EMC Clariion Systems: Global Hot Spares & Proactive Hot Spares

July 30th, 2009 No comments

The concept of Global Hot Spares has been supported in Clariion environments since the first generation of FC & CX platforms. Now the technology has been extended into the CX3 and then the CX4 platforms. The primary purpose of global hot sparing is to protect the system against disk drive failures.

Typically look at a CX4-960, which can be scaled up to 960TB of raw storage and can have as many as 960 disk drives in it. With certain failure rates guaranteed, large number of drives can create a higher probability of failure. Every storage manufacturer these days includes some sort of hot sparing technology in the storage subsystems. EMC started offering this technology to its customers as Global Hot Spares. Then came an era where some value add offerings were brought in for proactive failures to minimize the chance of data loss. This brought to the table a technology that is termed as Proactive Hot Spares, where proactively failing drive is determined and global hot spare is kicked in.

I believe flare release 24 started offering Proactive hot spares. With this Flare release customers can proactively initiate a kickoff of hot spares through Navisphere or Naviseccli against a suspect drive.

Depending on the RAID type implemented, the RAID Groups can withstand drive failures and can run in degraded state without data loss or data unavailability. With RAID 6 implemented, a machine can have as many as 2 drive failures in the same RAID group, with RAID 5, a machine can have as many as 1 drive failure in the same RAID group, with RAID 1/0, RAID 1 a machine can have as many as 1 drive failure in the RAID group without data loss.

Drives supported on Clariion CX, CX3, CX4, AX and AX4 systems typically are FC (Fiber Channel), SATA II and ATA drives.

A Global Hot Spare has to be configured in an EMC Clariion system as a single RAID Group (with one drive). Once the RAID Group is created, a LUN should be bound as a Global Hot Spare before it could be activated.

The following is the sequence of steps that take place on a Clariion Subsystem related to Global Hot Spares (Supported on CX, CX3, CX4 systems)

  1. Disk Drive failure: A disk drive failure in the system, Flare Code marks it bad.
  2. Hot spare invoked: A preconfigured Global Hot Spare is invoked based on the Global Hot Spare selection criteria.
  3. Rebuild: The Global Hot Spare is rebuilt from surviving raid group members.
  4. Failed drive replaced: Failed disk drive is replaced with a good drive by a Customer Engineer
  5. Copy Back: The Global Hot Spare copy has to finish before the new drive starts rebuilding. The rebuild or equalize happens in a sequential order of LBA (Logical Block Address) and not the LUNs bound no it.
  6. Return Hot Spare: Once the sync of new drive is finished, the hot spare is invalidated (zero’ed) and put back in the Global Hot Spare pool.

The following is the sequence of steps that take place on a Clariion Subsystem related to Proactive Hot Spares (Supported on CX300, CX500, CX700, CX3, CX4). Proactive Hot Spares essentially use the same drives that are configured as Global Hot Spares.

  1. Threshold of errors on Disk Drive: A drive gets hit with errors, it surpasses the number and type of those errors, and the flare code marks it as a potential candidate for failure.
  2. Proactive Hot Spare invoked: Based on the potential candidate’s (drive) type, drive size and bus location a Global Hot Spare is indentified and the process is kicked off for data rebuild.
  3. Potential candidate fails: Once the Proactive Hot Spare is synced, the flare code fails the indentified potential candidate.
  4. Failed drive replacement: The failed drive is replaced by a Customer Engineer
  5. Copy Back: From the proactive hot spare, the data is copied back to the newly inserted drive. The rebuilt or equalize happens in a sequential order of LBA (Logical Block Address).
  6. Return Proactive Hot Spare: Once the sync of new drive is finished, the hot spare is invalidated (zero’ed) and put back to the Global Hot Spares pool.

The Global Hot Spares Selection Criteria:

The following are the criteria’s that are followed with selection (invoke) of a Global Hot Spare when a potential proactive candidate is identified or disk drive is failed. In the sequence listed below, Drive type is the first selection, Size of the drive is the second selection and location of the Global Hot Spare is the third selection. Speed of the drive (RPM) is not a selection criterion.

  1. Type of Global Hot Spare Drive: As discussed above, Clariion Systems use three primary drive types. For FC and SATA II type drives, either or can be invoked against each other type. ATA drives can be invoked against an ATA drive failure.
  2. Size of Global Hot Spare: Upon a disk failure, the drive size (Global Hot Spare) is examined by Flare Code. The size of failed drive is not the key in invoking the hot spare, but the total space of all LUNs (bound) on the drive is used as a determination criteria.
  3. Location of Global Hot Spare: Based on the above two criteria, the location of the Global Hot Spare is considered as the third criteria. If the Global Hot Spare is on the same bus as the failed drive, it will be considered as the primary selection if the above two criteria’s are met. If the above two criteria’s are met and the drive is not on the same bus, then the Global Hot Spare is selected from other buses.

Other Considerations:

  1. RAID Types: For the copy of data, with RAID 3 and RAID 5 data on the hot spare is built using the parity drive. With RAID 6 raid types, data on the hot spare is built using the RP (row parity) and / or DP (Diagonal Parity) depending on the number of failures in the RAID Groups. For the RAID 1/0 and RAID 1, data on the hot spare is built using the surviving mirrors.
  2. Copy Times: The time required to copy or rebuilt a hot spare really depends on how large the drive is, the speed of the drive, the cache available on the drive, the cache available on the array, the type of the array, raid type and the current job processing on the array. Typical rebuilt times vary from 30 minutes to 90 minutes again depending upon how busy the storage subsystem is.
  3. Global hot Spare types: For every 30 drives (2 DAE’s of drives), consider having 1 drive as a Global hot spare. Also verify, for every drive type (size, speed) in the machine, you have at least one configured global hot spare. Good idea to have global hot spares on various different buses and spread across multiple Service Processors.
  4. Vault Drives: Vault Drives cannot be used for Global Hot Spares. The Vault drives are considered as the first 5 drives [ 0_0_0, 0_0_1, 0_0_2, 0_0_3, 0_0_4 ] on the Clariion System. If a vault drive fails, a Global Hot Spare takes over its position.
  5. Rotational Speed: Rotational Speed of the Global Hot Spare is not considered before invoking it. It might be a good idea to have Global Hot Spares running 15K RPM’s potentially with large size drives.
  6. Mixed Loop Speed: With certain Clariion Systems like CX3’s, available loop options are 4GB and / or 2GB and you can have a mixed loop speed in your machine, for hot spare selection the loop speed is not considered, in those cases it might be wise to have similar hot spares on both the 2GB and 4GB loops.