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Tony Pearson is a Master Inventor, Senior IT Architect and Event Content Manager for [IBM Systems for IBM Systems Technical University] events. With over 30 years with IBM Systems, Tony is frequent traveler, speaking to clients at events throughout the world.
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Miles per Gallon measures an effeciency ratio (amount of work done with a fixed amount of energy), not a speed ratio (distance traveled in a unit of time).
Given that IOPs and MB/s are the unit of "work" a storage array does, wouldn't the MPG equivalent for storage be more like IOPs per Watt or MB/s per Watt? Or maybe just simply Megabytes Stored per Watt (a typical "green" measurement)?
You appear to be intentionally avoiding the comparison of I/Os per Second and Megabytes per Second to Miles Per Hour?
May I ask why?
This is a fair question, Barry, so I will try to address it here.
It was not a typo, I did mean MPG (miles per gallon) and not MPH (miles per hour). It is always challenging to find an analogy that everyone can relate to explain concepts in Information Technology that might be harder to grasp. I chose MPG because it was closely related to IOPS and MB/s in four ways:
MPG applies to all instances of a particular make and model. Before Henry Ford and the assembly line, cars were made one at a time, by a small team of craftsmen, and so there could be variety from one instance to another. Today, vehicles and storage systems are mass-produced in a manner that provides consistent quality. You can test one vehicle, and safely assume that all similar instances of the same make and model will have the similar mileage. The same is true for disk systems, test one disk system and you can assume that all others of the same make and model will have similar performance.
MPG has a standardized measurement benchmark that is publicly available. The US Environmental Protection Agency (EPA) is an easy analogy for the Storage Performance Council, providing the results of various offerings to chose from.
MPG has usage-specific benchmarks to reflect real-world conditions.The EPA offers City MPG for the type of driving you do to get to work, and Highway MPG, to reflect the type ofdriving on a cross-country trip. These serve as a direct analogy to SPC having SPC-1 for Online transaction processing (OLTP) and SPC-2 for large file transfers, database queries and video streaming.
MPG can be used for cost/benefit analysis.For example, one could estimate the amount of business value (miles travelled) for the amount of dollar investment (cost to purchase gallons of gasoline, at an assumed gas price). The EPA does this as part of their analysis. This is similar to the way IOPS and MB/s can be divided by the cost of the storage system being tested on SPC benchmark results. The business value of IOPS or MB/s depends on the application, but could relate to the number of transactions processed per hour, the number of music downloads per hour, or number of customer queries handled per hour, all of which can be assigned a specific dollar amount for analysis.
It seemed that if I was going to explain why standardized benchmarks were relevant, I should find an analogy that has similar features to compare to. I thought about MPH, since it is based on time units like IOPS and MB/s, butdecided against it based on an earlier comment you made, Barry, about NASCAR:
Let's imagine that a Dodge Charger wins the overwhelming majority of NASCAR races. Would that prove that a stock Charger is the best car for driving to work, or for a cross-country trip?
Your comparison, Barry, to car-racing brings up three reasons why I felt MPH is a bad metric to use for an analogy:
Increasing MPH, and driving anywhere near the maximum rated MPH for a vehicle, can be reckless and dangerous,risking loss of human life and property damage. Even professional race car drivers will agree there are dangers involved. By contrast, processing I/O requests at maximum speed poses no additional risk to the data, nor possibledamage to any of the IT equipment involved.
While most vehicles have top speeds in excess of 100 miles per hour, most Federal, State and Local speed limits prevent anyone from taking advantage of those maximums. Race-car drivers in NASCAR may be able to take advantage of maximum MPH of a vehicle, the rest of us can't. The government limits speed of vehicles precisely because of the dangers mentioned in the previous bullet. In contrast, processing I/O requests at faster speeds poses no such dangers, so the government poses no limits.
Neither IOPS nor MB/s match MPH exactly.Earlier this week,I related IOPS to "Questions handled per hour" at the local public library, and MB/s to "Spoken words per minute" in those replies. If I tried to find a metric based on unit type to match the "per second" in IOPS and MB/s, then I would need to find a unit that equated to "I/O requests" or "MB transferred" rather than something related to "distance travelled".
In terms of time-based units, the closest I could come up with for IOPS was acceleration rate of zero-to-sixty MPH in a certain number of seconds. Speeding up to 60MPH, then slamming the breaks, and then back up to 60MPH, start-stop, start-stop, and so on, would reflect what IOPS is doing on a requestby request basis, but nobody drives like this (except maybe the taxi cab drivers here in Malaysia!)
Since vehicles are limited to speed limits in normal road conditions, the closest I could come up with for MB/s would be "passenger-miles per hour", such that high-occupancy vehicles like school buses could deliver more passengers than low-occupancy vehicles with only a few passengers.
Neither start-stops nor passenger-miles per hour have standardized benchmarks, so they don't work well for comparisonbetween vehicles.If you or anyone can come up with a metric that will help explain the relevance of standardized benchmarks better than the MPG that I already used, I would be interested in it.
You also mention, Barry, the term "efficiency" but mileage is about "fuel economy".Wikipedia is quick to point out that the fuel efficiency of petroleum engines has improved markedly in recent decades, this does not necessarily translate into fuel economy of cars. The same can be said about the performance of internal bandwidth ofthe backplane between controllers and faster HDD does not necessarily translate to external performance of the disk system as a whole. You correctly point this out in your blog about the DMX-4:
Complementing the 4Gb FC and FICON front-end support added to the DMX-3 at the end of 2006, the new 4Gb back-end allows the DMX-4 to support the latest in 4Gb FC disk drives.
You may have noticed that there weren't any specific performance claims attributed to the new 4Gb FC back-end. This wasn't an oversight, it is in fact intentional. The reality is that when it comes to massive-cache storage architectures, there really isn't that much of a difference between 2Gb/s transfer speeds and 4Gb/s.
Oh, and yes, it's true - the DMX-4 is not the first high-end storage array to ship a 4Gb/s FC back-end. The USP-V, announced way back in May, has that honor (but only if it meets the promised first shipments in July 2007). DMX-4 will be in August '07, so I guess that leaves the DS8000 a distant 3rd.
This also explains why the IBM DS8000, with its clever "Adaptive Replacement Cache" algorithm, has such highSPC-1 benchmarks despite the fact that it still uses 2Gbps drives inside. Given that it doesn't matter between2Gbps and 4Gbps on the back-end, why would it matter which vendor came first, second or third, and why call it a "distant 3rd" for IBM? How soon would IBM need to announce similar back-end support for it to be a "close 3rd" in your mind?
I'll wrap up with you're excellent comment that Watts per GB is a typical "green" metric. I strongly support the whole"green initiative" and I used "Watts per GB" last month to explain about how tape is less energy-consumptive than paper.I see on your blog you have used it yourself here:
The DMX-3 requires less Watts/GB in an apples-to-apples comparison of capacity and ports against both the USP and the DS8000, using the same exact disk drives
It is not clear if "requires less" means "slightly less" or "substantially less" in this context, and have no facts from my own folks within IBM to confirm or deny it. Given that tape is orders of magnitude less energy-consumptive than anything EMC manufacturers today, the point is probably moot.
I find it refreshing, nonetheless, to have agreed-upon "energy consumption" metrics to make such apples-to-apples comparisons between products from different storage vendors. This is exactly what customers want to do with performance as well, without necessarily having to run their own benchmarks or work with specific storage vendors. Of course, Watts/GB consumption varies by workload, so to make such comparisons truly apples-to-apples, you would need to run the same workload against both systems. Why not use the SPC-1 or SPC-2 benchmarks to measure the Watts/GB consumption? That way, EMC can publish the DMX performance numbers at the same time as the energy consumption numbers, and then HDS can follow suit for its USP-V.
I'm on my way back to the USA soon, but wanted to post this now so I can relax on the plane.
Last week, in Computer Technology Review's article [Tiering: Scale Up? Scale Out? Do Both], Mark Ferelli interviews fellow blogger Hu Yoshida, CTO of Hitachi Data Systems (HDS). Here's an excerpt:
"MF/CTR: A global cache should be required to implement that common pool that you’re talking about going across all tiers.
Hu/HDS: Right. So that is needed to get to all the resources. Now with our system, we can also attach external storage behind it for capacity so that as the storage ages out or becomes less active we can move it to the external storage. They would certainly have less performance capability, but you don’t need it for the stale data that we’re aging down. Right now we’re the only vendor that can provide this type of tiering.
If you look at other people who do virtualization like IBM’s SVC, the SVC has no storage within it because it’s sitting so if you attach any storage behind it, there is some performance degradation because you have this appliance sitting in front. That appliance is also very limited in cache and very limited in the number of storage boards on it. It cannot really provide you additional performance than what is attached behind it. And in fact, it will always degrade what is attached behind it because it’s not storage, where as our USP is storage and it has a global cache and it has thousands of port connections, load balancing and all that. So our front end can enhance existing storage that sits behind it."
This is not the first time I have had to correct Hu and others of misperceptions of IBM's SAN Volume Controller (SVC). This month marks my four year "blogoversary", and I seem to spend a large portion of my blogging time setting the record straight. Here are just a few of my favorite posts setting the record straight on SVC back in 2007:
Since day 1, SAN Volume Controllers has focused primarily on external storage. Initially, the early models had just battery-protected DRAM cache memory, but the most recent model of the SVC, the 2145-CF8, adds support for internal SLC NAND flash solid state drives. To fully appreciate how SVC can help improve the performance of the disks that are managed, I need to use some visual aids.
In this first chart, we look at a 70/30/50 workload. This indicates that 70 percent of the IOPS are reads, 30 percent writes, and 50 percent can be satisfied as cache hits directly from the SVC. For the reads, this means that 50 percent are read-hits satisfied from SVC DRAM cache, and 50 percent are read-miss that have to get the data from the managed disk, either from the managed disk's own cache, or from the actual spinning drives inside that managed disk array.
For writes, all writes are cache-hits, but some of them will be destaged to the managed disk. Typically, we find that a third of writes are over-written before this happens, so only two-thirds are written down to managed disk.
In this example, the SVC reduced the burden of the managed disk from 100,000 IOPS down to 55,000, which is 35,000 reads and 20,000 writes. Some have argued against putting one level of cache (SVC) in front of another level of cache (managed disk arrays). However, CPU processor designers have long recognized the value of hierarchical cache with L1, L2, L3 and sometimes even L4 caches. The cache-hits on SVC are faster than most disk system's cache-hits.
This is a Ponder curve, mapping millisecond response (MSR) times for different levels of I/O per second, named after the IBM scientist John Ponder that created them. Most disk array vendors will publish similar curves for each of their products. In this case, we see that 100,000 IOPS would cause a 25 millisecond response (MSR) time, but when the load is reduced to 55,000 IOPS, the average response time drops to only 7 msec.
To be fair, the SVC does introduce 0.06 msec of additional latency on read-misses, so let's call this 7.06 msec. This tiny amount of latency could be what Hu Yoshida was referring to when he said there was "some performance degradation". There are other storage virtualization products in the market that do not provide caching to boost performance, but rather just map incoming requests to outgoing requests, and these can indeed slow down every I/O they process. Perhaps Hu was thinking of those instead of IBM's SVC when he made his comments.
Of course, not all workloads are 70/30/50, and not every disk array is driven to its maximum capability, so your mileage may vary. As we slide down the left of the curve where things are flatter, the improvement in performance lowers.
IOPS before SVC
IOPS after SVC
MSR before SVC
MSR after SVC
Hitachi's offerings, including the HDS USP-V, USP-VM and their recently announced Virtual Storage Platform (VSP) sold also by HP under the name P9500, have similar architecture to the SVC and can offer similar benefits, but oddly the Hitachi engineers have decided to treat externally attached storage as second-class citizens instead. Hu mentions data that "ages out or becomes less active we can move it to the external storage." IBM has chosen not to impose this "caste" system onto its design of the SAN Volume Controller.
The SVC has been around since 2003, before the USP-V came to market, and has sold over 20,000 SVC nodes over the past seven years. The SVC can indeed improve performance of managed disk systems, in some cases by a substantial amount. The 0.06 msec latency on read-miss requests represents less than 1 percent of total performance in production workloads. SVC nearly always improves performance, and in the worst case, provides same performance but with added functionality and flexibility. For the most part, the performance boost comes as a delightful surprise to most people who start using the SVC.
To learn more about IBM's upcoming products and how IBM will lead in storage this decade, register for next week's webcast "Taming the Information Explosion with IBM Storage" featuring Dan Galvan, IBM Vice President, and Steve Duplessie, Senior Analyst and Founder of Enterprise Storage Group (ESG).
Continuing my catch-up on past posts, Jon Toigo on his DrunkenData blog, posted a ["bleg"] for information aboutdeduplication. The responses come from the "who's who" of the storage industry, so I will provide IBM'sview. (Jon, as always, you have my permission to post this on your blog!)
Please provide the name of your company and the de-dupe product(s) you sell. Please summarize what you think are the key values and differentiators of your wares.
IBM offers two different forms of deduplication. The first is IBM System Storage N series disk system with Advanced Single Instance Storage (A-SIS), and the second is IBM Diligent ProtecTier software. Larry Freeman from NetApp already explains A-SIS in the [comments on Jon's post], so I will focus on the Diligent offering in this post. The key differentiators for Diligent are:
Data agnostic. Diligent does not require content-awareness, format-awareness nor identification of backup software used to send the data. No special client or agent software is required on servers sending data to an IBM Diligent deployment.
Inline processing. Diligent does not require temporarily storing data on back-end disk to post-process later.
Scalability. Up to 1PB of back-end disk managed with an in-memory dictionary.
Data Integrity. All data is diff-compared for full 100 percent integrity. No data is accidentally discarded based on assumptions about the rarity of hash collisions.
InfoPro has said that de-dupe is the number one technology that companies are seeking today — well ahead of even server or storage virtualization. Is there any appeal beyond squeezing more undifferentiated data into the storage junk drawer?
Diligent is focused on backup workloads, which has the best opportunity for deduplication benefits. The two main benefits are:
Keeping more backup data available online for fast recovery.
Mirroring the backup data to another remote location for added protection. With inline processing, only the deduplicated data is sent to the back-end disk, and this greatly reduces the amount of data sent over the wire to the remote location.
Every vendor seems to have its own secret sauce de-dupe algorithm and implementation. One, Diligent Technologies (just acquired by IBM), claims that their’s is best because it collapses two functions — de-dupe then ingest — into one inline function, achieving great throughput in the process. What should be the gating factors in selecting the right de-dupe technology?
As with any storage offering, the three gating factors are typically:
Will this meet my current business requirements?
Will this meet my future requirements for the next 3-5 years that I plan to use this solution?
What is the Total Cost of Ownership (TCO) for the next 3-5 years?
Assuming you already have backup software operational in your existing environment, it is possible to determine thenecessary ingest rate. How many "Terabytes per Hour" (TB/h) must be received, processed and stored from the backup software during the backup window. IBM intends to document its performance test results of specific software/hardwarecombinations to provide guidance to clients' purchase and planning decisions.
For post-process deployments, such as the IBM N series A-SIS feature, the "ingest rate" during the backup only has to receive and store the data, and the rest of the 24-hour period can be spent doing the post-processing to find duplicates. This might be fine now, but as your data grows, you might find your backup window growing, and that leaves less time for post-processing to catch up. IBM Diligent does the processing inline, so is unaffected by an expansion of the backup window.
IBM Diligent can scale up to 1PB of back-end data, and the ingest rate does not suffer as more data is managed.
As for TCO, post-process solutions must have additional back-end storage to temporarily hold the data until the duplicates can be found. With IBM Diligent's inline methodology, only deduplicated data is stored, so less disk space is required for the same workloads.
Despite the nuances, it seems that all block level de-dupe technology does the same thing: removes bit string patterns and substitutes a stub. Is this technically accurate or does your product do things differently?
IBM Diligent emulates a tape library, so the incoming data appears as files to be written sequentially to tape. A file is a string of bytes. Unlike block-level algorithms that divide files up into fixed chunks, IBM Diligent performs diff-compares of incoming data with existing data, and identifies ranges of bytes that duplicate what already is stored on the back-end disk. The file is then a sequence of "extents" representing either unique data or existing data. The file is represented as a sequence of pointers to these extents. An extent can vary from2KB to 16MB in size.
De-dupe is changing data. To return data to its original state (pre-de-dupe) seems to require access to the original algorithm plus stubs/pointers to bit patterns that have been removed to deflate data. If I am correct in this assumption, please explain how data recovery is accomplished if there is a disaster. Do I need to backup your wares and store them off site, or do I need another copy of your appliance or software at a recovery center?
For IBM Diligent, all of the data needed to reconstitute the data is stored on back-end disks. Assuming that all of your back-end disks are available after the disaster, either the original or mirrored copy, then you only need the IBM Diligent software to make sense of the bytes written to reconstitute the data. If the data was written by backup software, you would also need compatible backup software to recover the original data.
De-dupe changes data. Is there any possibility that this will get me into trouble with the regulators or legal eagles when I respond to a subpoena or discovery request? Does de-dupe conflict with the non-repudiation requirements of certain laws?
I am not a lawyer, and certainly there are aspects of[non-repudiation] that may or may not apply to specific cases.
What I can say is that storage is expected to return back a "bit-perfect" copy of the data that was written. Thereare laws against changing the format. For example, an original document was in Microsoft Word format, but is converted and saved instead as an Adobe PDF file. In many conversions, it would be difficult to recreate the bit-perfect copy. Certainly, it would be difficult to recreate the bit-perfect MS Word format from a PDF file. Laws in France and Germany specifically require that the original bit-perfect format be kept.
Based on that, IBM Diligent is able to return a bit-perfect copy of what was written, same as if it were written to regular disk or tape storage, because all data is diff-compared byte-for-byte with existing data.
In contrast, other solutions based on hash codes have collisions that result in presenting a completely different set of data on retrieval. If the data you are trying to store happens to have the same hash code calculation as completely different data already stored on a solution, then it might just discard the new data as "duplicate". The chance for collisions might be rare, but could be enough to put doubt in the minds of a jury. For this reason, IBM N series A-SIS, that does perform hash code calculations, will do a full byte-for-byte comparison of data to ensure that data is indeed a duplicate of an existing block stored.
Some say that de-dupe obviates the need for encryption. What do you think?
I disagree. I've been to enough [Black Hat] conferences to know that it would be possible to read thedata off the back-end disk, using a variety of forensic tools, and piece together strings of personal information,such as names, social security numbers, or bank account codes.
Currently, IBM provides encryption on real tape (both TS1120 and LTO-4 generation drives), and is working withopen industry standards bodies and disk drive module suppliers to bring similar technology to disk-based storage systems.Until then, clients concerned about encryption should consider OS-based or application-based encryption from thebackup software. IBM Tivoli Storage Manager (TSM), for example, can encrypt the data before sending it to the IBMDiligent offering, but this might reduce the number of duplicates found if different encryption keys are used.
Some say that de-duped data is inappropriate for tape backup, that data should be re-inflated prior to write to tape. Yet, one vendor is planning to enable an “NDMP-like” tape backup around his de-dupe system at the request of his customers. Is this smart?
Re-constituting the data back to the original format on tape allows the original backup software to interpret the tape data directly to recover individual files. For example, IBM TSM software can write its primary backup copies to an IBM Diligent offering onsite, and have a "copy pool" on physical tape stored at a remote location. The physical tapes can be used for recovery without any IBM Diligent software in the event of a disaster. If the IBM Diligent back-end disk images are lost, corrupted, or destroyed, IBM TSM software can point to the "copy pool" and be fully operational. Individual files or servers could be restored from just a few of these tapes.
An NDMP-like tape backup of a deduplicated back-end disk would require that all the tapes are in-tact, available, and fully restored to new back-end disk before the deduplication software could do anything. If a single cartridge fromthis set was unreadable or misplaced, it might impact the access to many TBs of data, or render the entire systemunusable.
In the case of a 1PB of back-end disk for IBM Diligent, you would be having to recover over a thousand tapes back to disk before you could recover any individual data from your backup software. Even with dozens of tape drives in parallel, could take you several days for the complete process.This represents a longer "Recovery Time Objective" (RTO) than most people are willing to accept.
Some vendors are claiming de-dupe is “green” — do you see it as such?
Certainly, "deduplicated disk" is greener than "non-deduplicated" disk, but I have argued in past posts, supportedby Analyst reports, that it is not as green as storing the same data on "non-deduplicated" physical tape.
De-dupe and VTL seem to be joined at the hip in a lot of vendor discussions: Use de-dupe to store a lot of archival data on line in less space for fast retrieval in the event of the accidental loss of files or data sets on primary storage. Are there other applications for de-duplication besides compressing data in a nearline storage repository?
Deduplication can be applied to primary data, as in the case of the IBM System Storage N series A-SIS. As Larrysuggests, MS Exchange and SharePoint could be good use cases that represent the possible savings for squeezing outduplicates. On the mainframe, many master-in/master-out tape applications could also benefit from deduplication.
I do not believe that deduplication products will run efficiently with “update in place” applications, that is high levels of random writes for non-appending updates. OLTP and Database workloads would not benefit from deduplication.
Just suggested by a reader: What do you see as the advantages/disadvantages of software based deduplication vs. hardware (chip-based) deduplication? Will this be a differentiating feature in the future… especially now that Hifn is pushing their Compression/DeDupe card to OEMs?
In general, new technologies are introduced on software first, and then as implementations mature, get hardware-based to improve performance. The same was true for RAID, compression, encryption, etc. The Hifn card does "hash code" calculations that do not benefit the current IBM Diligent implementation. Currently, IBM Diligent performsLZH compression through software, but certainly IBM could provide hardware-based compression with an integrated hardware/software offering in the future. Since IBM Diligent's inline process is so efficient, the bottleneck in performance is often the speed of the back-end disk. IBM Diligent can get improved "ingest rate" using FC instead of SATA disk.
Sorry, Jon, that it took so long to get back to you on this, but since IBM had just acquired Diligent when you posted, it took me a while to investigate and research all the answers.
I'm down here in Australia, where the government is a bit stalled for the past two weeks at the moment, known formally as being managed by the [Caretaker government]. Apparently, there is a gap between the outgoing administration and the incoming administration, and the caretaker government is doing as little as possible until the new regime takes over. They are still counting votes, including in some cases dummy ballots known as "donkey votes", the Australian version of the hanging chad. Three independent parties are also trying to decide which major party they will support to finalize the process.
While we are on the topic of a government stalled, I feel bad for the state of Virginia in the United States. Apparently, one of their supposedly high-end enterprise class EMC Symmetrix DMX storage systems, supporting 26 different state agencies in Virginia, crashed on August 25th and now more than a week later, many of those agencies are still down, including the Department of Motor Vehicles and the Department of Taxation and Revenue.
Many of the articles in the press on this event have focused on what this means for the reputation of EMC. Not surprisingly, EMC says that this failure is unprecedented, but really this is just one in a long series of failures from EMC. It reminds me of the last time EMC had a public failure with a dual-controller CLARiiON a few months ago that stopped another company from their operations. There is nothing unique in the physical equipment itself, all IT gear can break or be taken down by some outside force, such as a natural disaster. The real question, though, is why haven’t EMC and the State Government been able to restore operations many days after the hardware was fixed?
In the Boston Globe, Zeus Kerravala, a data storage analyst at Yankee Group in Boston, is quoted as saying that such a high-profile breakdown could undermine EMC’s credibility with large businesses and government agencies. “I think it’s extremely important for them,’’ said Kerravala. “When you see a failure of this magnitude, and their inability to get a customer like the state of Virginia up and running almost immediately, all companies ought to look at that and raise their eyebrows.’’
Was the backup and disaster recovery solution capable of the scale and service level requirements needed by vital state
agencies? Had they tested their backups to ensure they were running correctly, and had they tested their recovery plans? Were they monitoring the success of recent backup operations?
Eventually, the systems will be back up and running, fines and penalties will be paid, and perhaps the guy who chose to go with EMC might feel bad enough to give back that new set of golf clubs, or whatever ridiculously expensive gift EMC reps might offer to government officials these days to influence the purchase decision making process.
(Note: I am not accusing any government employee in particular working at the state of Virginia of any wrongdoing, and mention this only as a possibility of what might have happened. I am sure the media will dig into that possibility soon enough during their investigations, so no sense in me discussing that process any further.)
So what lessons can we learn from this?
Lesson 1: You don't just buy technology, you also are choosing to work with a particular vendor
IBM stands behind its products. Choosing a product strictly on its speeds and feeds misses the point. A study IBM and Mercer Consulting Group conducted back in 2007 found that only 20 percent of the purchase decision for storage was from the technical capabilities. The other 80 percent were called "wrapper attributes", such as who the vendor was, their reputation, the service, support and warranty options.
Lesson 2: Losing a single disk system is a disaster, so disaster recovery plans should apply
IBM has a strong Business Continuity and Recovery Services (BCRS) services group to help companies and government agencies develop their BC/DR plans. In the planning process, various possible incidents are identified, recovery point objectives (RPO) and recovery time objectives (RTO) and then appropriate action plans are documentede on how to deal with them. For example, if the state of Virginia had an RPO of 48 hours, and an RTO of 5 days, then when the failure occurred on August 25, they could have recovered up to August 23 level data(48 hours prior to the incident) and be up and running by August 30 (five days after the incident). I don't personally know what RPO and RTO they planned for, but certainly it seems like they missed it by now already.
Lesson 3: BC/DR Plans only work if you practice them often enough
Sadly, many companies and government agencies make plans, but never practice them, so they have no idea if the plans will work as expected, or if they are fundamentally flawed. Just as we often have fire drills that force everyone to stop what they are doing and vacate the office building, anyone with an IT department needs to practice BC/DR plans often enough so that you can ensure the plan itself is solid, but also so that the people involved know what to do and their respective roles in the recovery process.
Lesson 4: This can serve as a wake-up call to consider Cloud Computing as an alternative option
Are you still doing IT in your own organization? Do you feel all of the IT staff have been adequately trained for the job? If your biggest disk system completely failed, not just a minor single or double drive failure, but a huge EMC-like failure, would your IT department know how to recover in less than five days? Perhaps this will serve as a wake-up call to consider alternative IT delivery options. The advantage of big Cloud Service Providers (Microsoft, Google, Yahoo, Amazon, SalesForce.com and of course, IBM) is that they are big enough to have worked out all the BC/DR procedures, and have enough resources to switch over to in case any individual disk system fails.
Well it's Tuesday again, and you know what that means! IBM Announcements!
For nearly 50 years, IBM has been leading the IT industry with its mainframe servers. Today, IBM announced its 12th generation mainframe in its [System z product family], the IBM zEnterprise EC12, or zEC12 for short. I joined IBM in 1986, and my first job was to work on DFHSM for the MVS operating system. The product is now known as DFSMShsm as part of the Data Facility Storage Management System, and the operating systems went through several name changes: MVS/ESA, OS/390, and lately z/OS. I was the lead architect for DFSMS up until 2001. I then switched to be part of the team that brought Linux to the mainframe. Both of these experiences come in handy as I deal with mainframe storage clients at the Tucson Executive Briefing Center.
Let's take a look at some recent developments over the past few years.
In the 9th and 10th generations (IBM System z9 and z10, respectively), IBM introduced the concept of a large "Enterprise Class", and a small "Business Class" to offer customer choice. These were referred to as the EC and BC models.
For the 12th generation, IBM kept the name "zEnterprise", but went back to the "EC" to refer to Enterprise Class. Rather than offer a separate "small" Business Class version, the zEC12 comes in 60 different sub-capacity levels. Many software vendors charge per core, or per [MIPS], so offering sub-capacity means that some portion of the processors are turned off, so the software license is lower. The top rating for the zEC12 is 78,000 MIPS. (I would have thought by now that we would have switched over to BIPS by now!)
If you currently have a z10 or z196, then it can be upgraded to zEC12. The zEC12 can attach to up to four zBX model 003 frames that can run AIX, Microsoft Windows and Linux-x86. If you currently have zBX model 002 frames, these can be upgraded to model 003.
The key enhancements reflect the three key initiatives:
Operational Analytics - Most analytics are done after-the-fact, but IBM zEnterprise can enable operational analytics in real-time, such as fraud detection while the person is using the credit card at a retail outlet, or online websites providing real-time suggestions for related products while the person is still adding items to their shopping card. Operational analytics provides not just the insight, but in a timely manner that makes it actionable. There is even work in place to [certify Hadoop on the mainframe].
Security and Resiliency - IBM is famous for having the most secure solutions. With industry-leading EAL5+ security rating, it beats out competitive offerings that are typically only EAL4 or lower. IBM has a Crypto Express4S card to provide tamper-proof co-processing for the system. IBM introduces the new "zAware" feature, which is like "Operational Analytics" pointed inward, evaluating all of the internal processes, error logs and traces, to determine if something needs to be fixed or optimized.
Cloud Agile - When people hear the phrase "Cloud Agile" they immeidately think of IBM System Storage, but servers can be Cloud Agile also, and the mainframe can run Linux and Java better, faster, and at a lower cost, than many competitve alternatives.
IBM Storage Strategy for the Smarter Computing Era
I presented this session on Thursday morning. It is a session I give frequently at the IBM Tucson Executive Briefing Center (EBC). IBM launched [Smarter Computing initiative at IBM Pulse conference]. My presentation covered the role of storage in Business Analytics, Workload Optimized Systems, and Cloud Computing.
Layer 8: Cloud Computing and the new IT Delivery Model
Ed Batewell, IBM Field Technical Support Specialist, presented this overview on Cloud Computing. The "Layer 8" is a subtle reference to the [7-layer OSI Model] for networking protocols. Ed cites insights from the [2011 IBM Global CIO Survey]. Of the 3000 companies surveyed, 60 percent plan to use or deploy clouds. In USA, 70 percent of CIOs have significant plans for cloud within the next 3-5 years. These numbers are double the statistics gleamed from the 2009 Global CIO survey. Clouds are one of IBM's big four initiatives, expecting to generate $7 Billion USD annual revenues by 2015.
IBM is recognized in the industry as one of "Big 5" vendors (Google, Yahoo, Microsoft, and Amazon round out the rest). As such, IBM has contributed to the industry a set of best practices known as the [Cloud Computing Reference Architect (36-page document)]. As is typical for IBM, this architecture is end-to-end complete, covering the three main participants for successful cloud deployments:
Consumers: the people and systems that use cloud computing services
Providers: the people, infrastructure and business operations needed to deliver IT services to consumers
Developers: the people and their development tools that create apps and platforms for cloud computing
IBM is working hard to eliminate all barriers to adoption for Cloud Computing. [Mirage image management] can patch VM images offline to address "Day 0" viruses. [Hybrid Cloud Integrator can help integrate new Cloud technologies to legacy applications. [IBM Systems Director VMcontrol] can manage VM images from z/VM on the mainframe, to PowerVM on UNIX servers, to VMware, Microsoft, Xen and KVM for x86 servers. IBM's [Cloud Service Provider Platform (CSP2)] is designed for Telecoms to offer Cloud Computing services. IBM CloudBurst is a "Cloud-in-a-Can" optimized stack of servers, storage and switches that can be installed in five days and comes in various "tee-shirt sizes" (Small, Medium, Large and Extra Large), depending on how many VMs you want to run.
Ed mentioned that companies trying to build their own traditional IT applications and environments, in an effort to compete against the cost-effective Clouds, reminded him of Thomas Thwaites' project of building a toaster from scratch. You can watch the [TED video, 11 minutes]:
An interesting project is [Reservoir] which IBM is working with other industry leaders to develop a way to seamlessly migrate VMs from one location to another, globally, without requiring shared storage, SAN zones or Ethernet subnets. This is similar to how energy companies buy and sell electricity to each other, as needed, or the way telecommunications companies allow roaming acorss each others networks.
IBM System Networking - Convergence
Jeff Currier, IBM Executive Consultant for the new IBM System Networking group, presented this session on Network Convergence. Storage is expected to grow 44x, from 0.8 [Zettabytes] in 2009, to 35 Zetabytes by the year 2020. The role of the network is growing in importance. IBM refers to this converged loss-less Ethernet network as "Convergence Enhanced Ethernet" (CEE), which Cisco uses the term "Data Center Ethernet" (DCE), and the rest of the industry uses "Data Center Bridging" (DCB).
To make this happen, we need to replace Spanning Tree Protocol [STP] that eliminates walking in circles in a multi-hop network configuration, with a new Layer 2 Multipathing (L2MP) protocol. The two competing for the title are Shortest Path Bridging (IEEE 802.1aq) and Transparent Interconnect of Lots of Links (IETF TRILL).
All roads lead to Ethernet. While FCoE has not caught on as fast as everyone hoped, iSCSI has benefited from all the enhancements to the Ethernet standard. iSCSI works in both lossy and lossless versions of Ethernet, and seems to be the preferred choice for new greenfield deployments for Small and Medium sized Businesses (SMB). Larger enterprises continue to use Fibre Channel (FCP and FICON), but might use single-hop FCoE from the servers to top-of-rack switches. Both iSCSI and FCoE scale well, but FCoE is considered more efficient.
IBM has a strategy, and is investing heavily in these standards, technologies, and core competencies.
Now that the US Recession has been declared over, companies are looking to invest in IT again. To help you plan your upcoming investments, here are some upcoming events in April.
SNW Spring 2010, April 12-15
IBM is a Platinum Plus sponsor at this [Storage Networking World event], to be held April 12-15 at the Rosen Shingle Creek Resort in Orlando, Florida. If you are planning to go, here's what you can go look for:
IBM booth at the Solution Center featuring the DS8700 and XIV disk systems, SONAS and the Smart Business Storage Cloud (SBSC), and various Tivoli storage software
IBM kiosk at the Platinum Galleria focusing on storage solutions for SAP and Microsoft environments
IBM Senior Engineer Mark Fleming presenting "Understanding High Availability in the SAN"
IBM sponsored "Expo Lunch" on Tuesday, April 13, featuring Neville Yates, CTO of IBM ProtecTIER, presenting "Data Deduplication -- It's not Magic - It's Math!"
IBM CTO Vincent Hsu presenting "Intelligent Storage: High Performance and Hot Spot Elimination"
IBM Senior Technical Staff Member (STSM) Gordon Arnold presenting "Cloud Storage Security"
One-on-One meetings with IBM executives
I have personally worked with Mark, Neville, Vincent and Gordon, so I am sure they will do a great job in their presentations. Sadly, I won't be there myself, but fellow blogger [Rich Swain from IBM] will be at the event to blog about all the actviities there.
Jim Stallings - General Manager, Global Markets, IBM Systems and Technology Group
Scott Handy - Vice President, WW Marketing, Power Systems, IBM Systems and Technology Group
Dan Galvan - Vice President, Marketing & Strategy, Storage and Networking Systems, IBM Systems and Technology Group
Inna Kuznetsova - Vice President, Marketing and Sales Enablement, Systems Software, IBM Systems and Technology Group
Jeanine Cotter - Vice President, Systems Services, IBM Global Technology Services
The webinar will include client testimonials from various companies as well.
Dynamic Infrastructure Executive Summit, April 27-29
I will be there, at this this 2-and-a-half-day [Executive Summit] in Scottsdale, Arizona, to talk to company executives. Discover how IBM can help you manage your ever-increasing amount of information with an end-to-end, innovative approach to building a dynamic infrastructure. You will learn all of our innovative solutions and find out how you can effectively transform your enterprise for a smarter planet.
In my last blog post [Full Disk Encryption for Your Laptop] explained my decisions relating to Full-Disk Encryption (FDE) for my laptop. Wrapping up my week's theme of Full-Disk Encryption, I thought I would explain the steps involved to make it happen.
Last April, I switched from running Windows and Linux dual-boot, to one with Linux running as the primary operating system, and Windows running as a Linux KVM guest. I have Full Disk Encryption (FDE) implemented using Linux Unified Key Setup (LUKS).
Here were the steps involved for encrypting my Thinkpad T410:
Step 0: Backup my System
Long-time readers know how I feel about taking backups. In my blog post [Separating Programs from Data], I emphasized this by calling it "Step 0". I backed up my system three ways:
Backed up all of my documents and home user directory with IBM Tivoli Storage Manager.
Backed up all of my files, including programs, bookmarks and operating settings, to an external disk drive (I used rsync for this). If you have a lot of bookmarks on your browser, there are ways to dump these out to a file to load them back in the later step.
Backed up the entire hard drive using [Clonezilla].
Clonezilla allows me to do a "Bare Machine Recovery" of my laptop back to its original dual-boot state in less than an hour, in case I need to start all over again.
Step 1: Re-Partition the Drive
"Full Disk Encryption" is a slight misnomer. For external drives, like the Maxtor BlackArmor from Seagate (Thank you Allen!), there is a small unencrypted portion that contains the encryption/decryption software to access the rest of the drive. Internal boot drives for laptops work the same way. I created two partitions:
A small unencrypted partition (2 GB) to hold the Master Boot Record [MBR], Grand Unified Bootlloader [GRUB], and the /boot directory. Even though there is no sensitive information on this partition, it is still protected the "old way" with the hard-drive password in the BIOS.
The rest of the drive (318GB) will be one big encrypted Logical Volume Manager [LVM] container, often referred to as a "Physical Volume" in LVM terminology.
Having one big encrypted partition means I only have to enter my ridiculously-long encryption password once during boot-up.
Step 2: Create Logical Volumes in the LVM container
I create three logical volumes on the encrypted physical container: swap, slash (/) directory, and home (/home). Some might question the logic behind putting swap space on an encrypted container. In theory, swap could contain sensitive information after a system [hybernation]. I separated /home from slash(/) so that in the event I completely fill up my home directory, I can still boot up my system.
Step 3: Install Linux
Ideally, I would have lifted my Linux partition "as is" for the primary OS, and a Physical-to-Virtual [P2V] conversion of my Windows image for the guest VM. Ha! To get the encryption, it was a lot simpler to just install Linux from scratch, so I did that.
Step 4: Install Windows guest KVM image
The folks in our "Open Client for Linux" team made this step super-easy. Select Windows XP or Windows 7, and press the "Install" button. This is a fresh install of the Windows operating system onto a 30GB "raw" image file.
(Note: Since my Thinkpad T410 is Intel-based, I had to turn on the 'Intel (R) Virtualization Technology' option in the BIOS!)
There are only a few programs that I need to run on Windows, so I installed them here in this step.
Step 5: Set up File Sharing between Linux and Windows
In my dual-boot set up, I had a separate "D:" drive that I could access from either Windows or Linux, so that I would only have to store each file once. For this new configuration, all of my files will be in my home directory on Linux, and then shared to the Windows guest via CIFS protocol using [samba].
In theory, I can share any of my Linux directories using this approach, but I decide to only share my home directory. This way, any Windows viruses will not be able to touch my Linux operating system kernels, programs or settings. This makes for a more secure platform.
Step 6: Transfer all of my files back
Here I used the external drive from "Step 0" to bring my data back to my home directory. This was a good time to re-organize my directory folders and do some [Spring cleaning].
Step 7: Re-establish my backup routine
Previously in my dual-boot configuration, I was using the TSM backup/archive client on the Windows partition to backup my C: and D: drives. Occasionally I would tar a few of my Linux directories and storage the tarball on D: so that it got included in the backup process. With my new Linux-based system, I switched over to the Linux version of TSM client. I had to re-work the include/exclude list, as the files are different on Linux than Windows.
One of my problems with the dual-boot configuration was that I had to manually boot up in Windows to do the TSM backup, which was disruptive if I was using Linux. With this new scheme, I am always running Linux, and so can run the TSM client any time, 24x7. I made this even better by automatically scheduling the backup every Monday and Thursday at lunch time.
There is no Linux support for my Maxtor BlackArmor external USB drive, but it is simple enough to LUKS-encrypt any regular external USB drive, and rsync files over. In fact, I have a fully running (and encrypted) version of my Linux system that I can boot directly from a 32GB USB memory stick. It has everyting I need except Windows (the "raw" image file didn't fit.)
I can still use Clonezilla to make a "Bare Machine Recovery" version to restore from. However, with the LVM container encrypted, this renders the compression capability worthless, and so takes a lot longer and consumes over 300GB of space on my external disk drive.
Backing up my Windows guest VM is just a matter of copying the "raw" image file to another file for safe keeping. I do this monthly, and keep two previous generations in case I get hit with viruses or "Patch Tuesday" destroys my working Windows image. Each is 30GB in size, so it was a trade-off between the number of versions and the amount of space on my hard drive. TSM backup puts these onto a system far away, for added protection.
Step 8: Protect your Encryption setup
In addition to backing up your data, there are a few extra things to do for added protection:
Add a second passphrase. The first one is the ridiculously-long one you memorize faithfully to boot the system every morning. The second one is a ridiculously-longer one that you give to your boss or admin assistant in case you get hit by a bus. In the event that your boss or admin assistant leaves the company, you can easily disable this second passprhase without affecting your original.
Backup the crypt-header. This is the small section in front that contains your passphrases, so if it gets corrupted, you would not be able to access the rest of your data. Create a backup image file and store it on an encrypted USB memory stick or external drive.
If you are one of the lucky 70,000 IBM employees switching from Windows to Linux this year, Welcome!
Jim is an IBM Fellow for IBM Systems and Technology Group. There are only 73 IBM Fellows currently working for IBM, and this is the highest honor IBM can bestow on an employee. He has been working with IBM since 1968.
He is tasked with predicting the future of IT, and help drive strategic direction for IBM. Cost pressures, requirements for growth, accelerating innovation and changing business needs help influence this direction.
IBM's approach is to integrate four different "IT building blocks":
Scale-up Systems, like the IBM System Storage DS8000 and TS3500 Tape Library
Resource Pools, such as IBM Storage Pools formed from managed disks by IBM SAN Volume Controller (SVC)
Integrated stacks and appliances, integrated software and hardware stacks, from Storwize V7000 to full rack systems like IBM Smart Analytics Server or CloudBurst.
Mobility of workloads and resources requires unified end-to-end service management. Fortunately, IBM is the #1 leader in IT Service Management solutions.
Jim addressed three myths:
Myth 1: IT Infrastructures will be homogenous.
Jim feels that innovations are happening too rapidly for this to ever happen, and is not a desirable end-goal. Instead, a focus to find the right balance of the IT building blocks might be a better approach.
Myth 2: All of your problems can be solved by replacing everything with product X.
Jim feels that the days of "rip-and-replace" are fading away. As IBM Executive Steve Mills said, "It isn't about the next new thing, but how well new things integrate with established applications and processes."
Myth 3: All IT will move to the Cloud model.
Jim feels a substantial portion of IT will move to the Cloud, but not all of it. There will always be exceptions where the old traditional ways of doing things might be appropriate. Clouds are just one of the many building blocks to choose from.
Jim's focus lately has been finding new ways to take advantage of virtualization concepts. Server, storage and network virtualization are helping address these challenges through four key methods:
Sharing - virtualization that allows a single resource to be used by multiple users. For example, hypervisors allow several guest VM operating systems share common hardware on a single physical server.
Aggregation - virtualization that allows multiple resources to be managed as a single pool. For example, SAN Volume Controller can virtualize the storage of multiple disk arrays and create a single storage pool.
Emulation - virtualization that allows one set of resources to look and feel like a different set of resources. Some hypervisors can emulate different kinds of CPU processors, for example.
Insulation - virtualization that hides the complexity from the end-user application or other higher levels of infrastructure, making it easier to make changes of the underlying managed resources. For example, both SONAS and SAN Volume Controller allow disk capacity to be removed and replaced without disruption to the application.
In today's economy, IT transformation costs must be low enough to yield near-term benefits. The long-term benefits are real, but near-term benefits are needed for projects to get started.
What set's IBM ahead of the pack? Here was Jim's list:
100 Years of Innovation, including being the U.S. Patent leader for the last 18 years in a row
IBM's huge investment in IBM Research, with labs all over the globe
Leadership products in a broad portfolio
Workload-optimized designs with integration from middleware all the way down to underlying hardware
Comprehensive management software for IBM and non-IBM equipment
Clod is an IBM Distinguished Engineer and Chief Technical Strategist for IBM System Storage. His presentation focused on trends and directions in the IT storage industry. Clod started with five workload categories:
To address these unique workload categories, IBM will offer workload-optimized systems. The four drivers on the design for these are performance, efficiency, scalability, and integration. For example, to address performance, companies can adopt Solid-State Drives (SSD). Unfortunately, these are 20 times more expensive dollar-per-GB than spinning disk, and the complexity involved in deciding what data to place on SSD was daunting. IBM solved this with an elegant solution called IBM System Storage Easy Tier, which provides automated data tiering for IBM DS8000, SAN Volume Controller (SVC) and Storwize V7000.
For scalability, IBM has adopted Scale-Out architectures, as seen in the XIV, SVC, and SONAS. SONAS is based on the highly scalable IBM General Parallel File System (GPFS). File systems are like wine, they get better with age. GPFS was introduced 15 years ago, and is more mature than many of the other "scalable file systems" from our competition.
Areal Density advancements on Hard Disk Drives (HDD) are slowing down. During the 1990s, the IT industry enjoyed 60 to 100 percent annual improvement in areal density (bits per square inch). In the 2000s, this dropped to 25 to 40 percent, as engineers are starting to hit various physical limitations.
Storage Efficiency features like compression have been around for a while, but are being deployed in new ways. For example, IBM invented WAN compression needed for Mainframe HASP. WAN compression became industry standard. Then IBM introduced compression on tape, and now compression on tape is an industry standard. ProtecTIER and Information Archive are able to combine compression with data deduplication to store backups and archive copies. Lastly, IBM now offers compression on primary data, through the IBM Real-Time Compression appliance.
For the rest of this decade, IBM predicts that tape will continue to enjoy (at least) 10 times lower dollar-per-GB than the least expensive spinning disk. Disk and Tape share common technologies, so all of the R&D investment for these products apply to both types of storage media.
For integration, IBM is leading the effort to help companies converge their SAN and LAN networks. By 2015, Clod predicts that there will be more FCoE purchased than FCP. IBM is also driving integration between hypervisors and storage virtualization. For example, IBM already supports VMware API for Array Integration (VAAI) in various storage products, including XIV, SVC and Storwize V7000.
Lastly, Clod could not finish a presentation without mentioning Cloud Computing. Cloud storage is expected to grow 32 percent CAGR from year 2010 to 2015. Roughly 10 percent of all servers and storage will be in some type of cloud by 2015.
As is often the case, I am torn between getting short posts out in a timely manner versus spending some more time to improve the length and quality of information, but posted much later. I will spread out the blog posts in consumable amounts throughout the next week or two, to achieve this balance.
To avoid overwhelming people with too many features and functions, IBM decided to keep things simple for the first release. Let's take a look:
The base frame (2231-IA3) supports a single collection, from as small as 3.6 TB to as large as 72 TB of usable capacity. You can attach one expansion frame (2231-IS3) that holds two additional collections, 63 TB usable capacity for each collection. Disk capacity is increased in eight-drive (half-drawer) increments of 3.6 TB usable capacity each. A full configured IA system (304 drives, 1 TB raw capacity per drive) provides 198 TB usable capacity.
Of course, that is just the disk side of the solution. Like its predecessor, the IBM System Storage DR550, the IA v1.1 can also attach to external tape storage to store and protect petabytes (PB) of archive data. Hundreds of different IBM and non-IBM tape drives and libraries are supported, so that this can be easily incorporated into existing tape environments.
Each collection can be configured to one of three protection levels: basic, intermediate, and maximum.
Basic protection provides RAID protection of data using standard NFS group/user controls for access to read and write data. This can be useful for databases that need full read/write access. Users can assign expiration dates, but in Basic mode they can delete the data before the expiration date is reached.
Intermediate adds Non-Erasable Non-Rewriteable (NENR) protection against user actions to delete or modify protected data. However, similar to IBM N series "Enterprise SnapLock", intermediate mode allows authorized storage admins to clean up the mess, increase or reduce retention periods, and delete data if it is inadvertently protected. I often refer to this as "training wheels" for those who are trying to work out their workflow procedures before moving on to Maximum mode.
Maximum provides the strictest NENR protection for business, legal, government and industry requirements, comparable to IBM N series "Compliance SnapLock" mode, for data that traditionally were written to WORM optical media. Data cannot be deleted until the retention period ends. Retention periods of individual files and objects can be increased, but not decreased. Retention Hold (often referred to as Litigation Hold) can be used to keep a set of related data even longer in specific circumstances.
You can decide to upgrade your protection after data is written to a collection. Basic mode can be upgraded to Intermediate mode, for example, or Intermediate mode upgraded to Maximum.
To keep things simple, v1.1 of the Information Archive supports only two industry standard protocols: NFS and SSAM API. The NFS option allows standard file commands to read/write data. The System Storage Archive Manager (SSAM) API allows smooth transition from earlier IBM System Storage DR550 deployments. With this announcement, IBM will [discontinue selling the DR550 DR2 models].
As we say here at IBM, "Today is the best day to stop using EMC Centera." For more information, see the
IBM [Announcement Letter].