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author of the Inside System Storage series of books. This blog is for the open exchange of ideas relating to storage and storage networking hardware, software and services. You can also follow him on Twitter @az990tony.
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The IBM Storage and Storage Networking Symposium concludes today. As typical for manysuch conferences, it ended at noon, so that people can catch airline flights.
TS1120 Tape Encryption - Customer Experiences
Jonathan Barney had implemented many deployments of tape encryption, and shared hisexperiences at two customer locations.
The first company had decided to implement their EKM servers on dedicated 64-bitWindows servers. They had three sites, one in Chicago, Alphareta, and New York City,each with two EKM servers. Each library had a single TS3500 tape library, and pointedto four EKM servers, two local, and two remote.
The clever trick was managing the keystore. They decided that EKM-1 was their trustedsource, made all changes to that, and then copied it to the other five EKM servers.His team deployed one site at a time, which turned out to be ok, but he would notrecommend it. Better to design your complete solution, and make sure that all librariescan access all EKM servers.
This company decided to have a single key-label/key-pair for all three locations, but change it every 6 months. You have to keep the old keys for as long as you have tapesencrypted with those keys, perhaps 10-20 years.The customer found the IBM encryption implementation "elegant" and it can be easily replicated to a fourth site if needed.
The second company had both z/OS and Sun Solaris. Initially they planned to have botha hardware-based keystore on System z, and software-based keystore on Sun, but they realized that System z version was so much more secure and reliable, that it made nosense to have anything on the Sun Solaris platform.
On System z, they had two EKM images, and used VIPA to ensure load balancing fromthe library. Tapes written from z/OS used DFSMS Data Class to determine which tapesare encrypted and which aren't. All Tapes written from Sun Solaris were encryptied, written to a separate logical library partition of the TS3500, which in turn contactedthe System z for the EKM management to provide the keys to use for the encryption.
The "gotcha" for this case was that when they tested Disaster Recovery, they had torecover the two EKM servers first, before any other restores could take place, and thistook way too long. Instead, they developed a scaled-down 10-volume "rescue recovery" z/OS image that would contain the RACF database and all EKM related software to actas the keystore during a disaster recovery. Anytime they make updates, they only haveto dump 10 volumes to tape. Restore time is down to only 2 hours.
He gave this advice to deploy tape encryption:
Some third party z/OS security products, like Computer Associates Top Secret orACF2, require some PTFs to work with the EKM. The latest IBM RACF is good to go.
Getting IP support from IOS to OMVS requires IPL.
At one customer, an OMVS monitor software program killed the EKM because it wasn'tin their list of "acceptable Java programs". They updated the list and EKM ran fine.
DO not update EKM properties file while EKM is running. EKM keeps a lot of stuffin memory, and when it is recycled, copies this back to the EKM properties file, reversing any changes you may have done. It is best to shut down EKM, update theproperties file, then start up EKM back up again. This is why you should always haveat least two EKM servers for redundancy.
TSM for Linux on System z
Randy Larson from our Tivoli group presented this session.There is a lot of interest in deploying IBM Tivoli Storage Manager backup and archivesoftware on Linux for System z. Many customers are already invested in a mainframeinfrastructure, may have TSM for z/OS or z/VM, and want the newer features and functions that are available for TSM on Linux.
TSM has special support for Lotus Domino, Oracle, DB2 and WebSphere Application Servers.TSM clients can send backup data to a TSM server internally via Hipersockets, a virtualLAN feature on the System z platform that uses shared memory to emulate TCP/IP stack.
One of the big questions is whether to run Linux as guests under z/VM, or natively onLPAR. The general deployment is to carve an LPAR and run Linux natively untilyour server and storage administration staff have taken z/VM training classes. Oncetrained, they can easily move native LPAR images to z/VM guests. Unlike VMware that takesa hefty 40% overhead on x86 platforms to manage guests, z/VM only takes 5-10% overhead.
For the TSM database and disk storage pools, Randy recommends FC/SCSI disk, with ext3 file system, combined with LVM2 into logical volumes. ECKD disk and reiserfsworks too. Avoid use of z/VM minidisks. Under LVM2, consider 32KB stripes for the TSM database, and 256KB stripes for the disk storage pools. For multipathing, usefailover rather than multibus method. Read IC45459 before you activate "directio".
The TSM for Linux on z is very much like the TSM on AIX or Windows, and not like theTSM for z/OS. For tape, TSM for Linux on z does not support ESCON/FICON attached tape,you need to use FC/SCSI attached tape and tape libraries. TSM owns the library anddrives it uses, so give it a logical library partition separate from z/OS. ForSun/StorageTek customers, TSM works with or without the Gersham Enterprise Distrbu-Tape(EDT) software. Use the IBM-provided drivers for IBM tape. For non-IBM tape, TSM providessome drivers that you can use instead.
That wraps up my week. This was a great conference! If you missed it, look for the one in Montpelier, France this October. Check out the list of IBM Technical Conferencesto find others that might interest you.
Continuing my theme of "Innovation that matters", I thought I would cover MapQuest and NeverLost.
When Shawn Callahan on Anecdote wrote[Our need for the knowledge worker is over], he was referring to the fact that we no longer need the term "knowledge worker", because practically everyone isa "knowledge worker" today. He asks "How does knowledge help us to work better?"
It is said that as much as 30 percent of a knowledge worker's time is spent looking for information to do their jobs. This could be information to make a decision, decide between several choices, take specific action, or schedule when these actions should take place. The logistics of planning a business trip, and actually navigating in unfamiliarsurroundings, is a good example of this, and presents some unique challenges.
Before these technologies
Before these technologies, to plan a trip involved finding someone who lives or has been to the destination city,can recommend hotels and restaurants near the meeting facility, and can suggest approximate times it would take to drive from one place to another. I would bring a compass, and would shop for a city map, either before leaving, or upon arrival.
On one trip to Raleigh, I asked a local IBMer who lived in Raleigh for a hotel recommendation. The hotel was nice,but involved a long 45-60 minute commute each day to the meeting facility. When I asked her why she suggested thatparticular hotel, she said it was because it was "close to the airport". I have since learned never to ask for "best" of anything, as this is subject to such interpretation.
On another trip, I was travelling with a colleague in Germany. He asked how I knew which bus to take, and which bus stop to wait at. I pulled out my compass, and told him that based on the schedule, the bus that went in a specific directionmust be the correct one. The entire bus load of people burst out laughing, that we fit the universal stereotype ofmen who refuse to ask for directions. This method works only in Germany, where timeliness is next to godliness. In other countries, time schedules are more of a suggestion.
Sometimes, maps of the destination city were not always easy to find. Now with the Internet and Google Earth, maps are available before leaving on the trip. (See my post on Inner Workings of Storage which discusses how Google Earth works.)
I like using MapQuest, available online at [mapquest.com], and have not yet looked into the similar systems from Google or Yahoo. I map out each leg of my trip that involves driving, walking or trains. These are oftenairport-to-hotel, hotel-to-meeting, meeting-to-airport. Having a feel for the time and distances between locationshelps choose hotels and restaurants, when to leave, and so on.
I even use MapQuest in Tucson. Recently, a route I generated to visit a friend across town took into accountconstruction on Highway I-10 that has been going on for a while, where 8 miles of on-ramps are closed, and routed me around this mess accordingly. This is one key advantage over a static map, either a paper map, or downloaded from Google Earth.
While MapQuest may not always choose the "best" route, it always finds "a route" that works, and generally works for me.
A few problems with a MapQuest print-out I have found are:
It is on paper, which could impact driving, as I have to look away from the road to look at the instructions.
If it can't find a specific address, it provides generic instructions, and often, this involves airports.
It often starts with "Head Northeast...", so unless you brought your compass, or can tell what direction you are pointing from Sun, Moon or stars, you may end up leaving in the wrong direction.
Recently, I checkmarked the "Request NeverLost" box on my Hertz Gold profile, and now I seem to get NeverLost innearly every rental. The system is based on the[Global Positioning System] set of satellites,complemented by a CD-based street information and yellow pages data for US and Canada, stored in the trunk.
The NeverLost system knows which way the car is oriented, can tell which direction you are driving, and tell youwith voice prompts to be in the left lane, right lane, and when to make left and right turns. No need for a compassor any knowledge of which way is North, East, West or South.
I also like that it gives you three choices for route: (a) Shortest time, (b) Most use of Highways, and (c) Least use of Highways. This came in handy when I was in Toronto last week. Apparently, the 407 Highway had recently implementedan Electronic Toll Road (ETR) which bills based on license plate. While this system is fine for residents, it isnot designed for rental car companies. Hertz left a note in my car warning me NOT to use the 407 highway, or I wouldbe charged an $8.50 dollar penalty. I chose "Least use of Highways" and proceeded to tour the city of Toronto for90 minutes from the Pearson Airport to my hotel in Markham, a trip that would have only taken 20 minutes otherwise.
Once you enter your destination street address, it can estimate the distance to get there. This is not a quick process, as there is no keyboard, you have to enter each letter using up/down/left/right keys. You can enter thename of the street, hotel or restaurant. To find "Sal Grosso" restaurant in Smyrna, it was at 1927 Powers Ferry Road,but NeverLost said that Powers Ferry only went from 2750-6350. I had to select 2750 and then hope to be close enough.
In Dallas, I tried to find "P. F. Chang's" restaurant, and you have to make sure that the periods and spaces are entered exactly. I ended up looking for restaurants in Grapevine, Texas, and then just going through the list ofall that start with the letter "P".
Another issue is that sometimes it takes awhile to find the satelites in the sky. I get the car started, I hit theenter button to get the NeverLost started, enter the address, and then it starts looking for satellites? Why doesn'tit look for satellites while you spend 3-5 minutes trying to enter the street address?In my case, I take out my MapQuest print-out, head in the right direction, and hope that NeverLost catches upeventually, in time to help me get to the final location.
It is not clear how often Hertz updates the CDrom that contains the street and yellow pages data. About 30-40 percent of the time, it can't find the street address I am looking for, and I have to be creative on howto get me in the general area.
Part of the problems is that I have not read the entire instruction manual, and do not have time to learn itwhen I am in the car driving. I might have to put this on my reading to-do list before my next trip. Some ofmy other colleagues have purchased their own GPS-based systems, like those from Garmin or Magellan, so that theyalways have it available, and they always know how to use it. This has the advantage that you can use it when walking around, or in your own car when you are home, as well.
Despite these few problems, I am impressed on the innovations involved to make this all happen. All of the mapping information was stored, transmitted, searched, and then plotted in a manner that provides specificinformation that you need to get the job done. For now, I will probably use a combination of these to planand travel on my business trips. Wouldn't it be nice if other areas in your life had this kind of support?
In yesterday's post, [IBM Information Infrastructure launches today], I explained how this strategic initiative fit into IBM's New EnterpriseData Center vision. For those who prefer audio podcasts, here is Marissa Benekos interviewing Andy Monshaw, IBM General Manager of IBM System Storage.
This post will focus on Information Availability, the first of the four-part series this week.
Here's another short 2-minute video, on Information Availability
I am not in marketing department anymore, so have no idea how much IBM spentto get these videos made, but hate for the money to go wasted. I suspect theonly way they will get viewed is if I include them in my blog. I hope youlike them.
As with many IT terms, "availability" might conjure up different meanings for different people.
Some can focus on the pure mechanics of delivering information. An information infrastructure involves all of thesoftware, servers, networks and storage to bring information to the application or end user, so all of the chainsin the link must be highly available: software should not crash, servers should have "five nines" (99.999%) uptime, networks should be redundant, and storage should handle the I/O request with sufficient performance. For tape libraries, the tape cartridge must be available, robotics are needed to fetch the tape, and a drive must be available toread the cartridge. All of these factors represent the continuous operations and high availability features of business continuity.
In addition to the IT equipment, you need to make sure your facilities that support that equipment, such aspower and cooling, are also available.Independent IT analyst Mark Peters from Enterprise Strategy Group (ESG) summarizes his shock about the findings in a recent [survey commissioned by Emerson Network Power]on his post [Backing Up Your Back Up]. Here is an excerpt:
"The net take-away is that the majority of SMBs in the US do not have back-up power systems. As regional power supplies get more stretched in many areas, the possibility of power outages increases and obviously many SMBs would be vulnerable. Indeed, while the small business decision makers questioned for the survey ranked such power outages ahead of other threats (fires, government regulation, weather, theft and employee turnover) only 39% had a back-up power system. Yeah, you could say, but anything actually going wrong is unlikely; but apparently not, as 79% of those surveyed had experienced at least one power outage during 2007. Yeah, you might say, but maybe the effects were minor; again, apparently not, since 42% of those who'd had outages had to actually close their businesses during the longest outages. The DoE says power outages cost $80 billion a year and businesses bear 98% of those costs."
Others might be more concerned about outages resulting from planned and unplanned downtime. Storage virtualizationcan help reduce planned downtime, by allowing data to be migrated from one storage device to another withoutdisrupting the application's ability to read and write data. The latest "Virtual Disk Mirroring" (VDM) feature of the IBM System Storage SAN Volume Controller takes it one stepfurther, providing high-availability even for entry-level and midrange disk systems managed by the SVC.For unplanned downtime, IBM offers a complete range of support, from highly available clusters, two-site and three-site disaster recovery support, and application-aware data protection through IBM Tivoli Storage Manager.
Many outages are caused by human error, and in many cases it is the human factor that prevent quick resolution.Storage admins are unable to isolate the failing component, identify the configuration or provide the appropriateproblem determination data to the technical team ready to offer support and assistance. For this, IBM TotalStorageProductivity Center software, and its hardware-version the IBM System Storage Productivity Center, can helpreduce outage time and increase information availability. It can also provide automation to predict or provideearly warning of impending conditions that could get worse if not taken care of.
But perhaps yet another take on information availability is the ability to find and communicate the right informnationto the right people at the right time. Recently, Google announced a historic milestone, their search engine nowindexes over [One trillion Web pages]!Google and other search engines have changed the level of expectations for finding information. People ask whythey can find information on the internet so quickly, yet it takes weeks for companies to respond to a judge foran e-discovery request.
Lastly, the team at IBM's[Eightbar blog] pointedme to Mozilla Lab's Ubiquity project for their popular FireFox browser. This project aims to help people communicate the information in a more natural way, rather than unfriently URL links on an email. It is still beta, of course, but helps show what "information availability" might be possible in the near future.Here is a 7-minute demonstration:
For those who only read the first and last paragraphs of each post, here is my recap:Information Availability includes Business Continuity and Data Protection to facilitatequick recovery, storage virtualization to maximize performance and minimize planned downtime, infrastructure management and automation to reduce human error, and the ability to find and communicate information to others.
This week I am in Japan, so my week's theme will center around travel, speaking at conferences, and Japan itself. I first travelled to Japan in the late 1980s, to visit a college friend who was working for Ford Motor Company, on assignment in Japan as liasion to Mazda Corp.
Back then, the only Japanese phrase I knew was "Wakarimashta" which means "I know" or "I understand". If you only know one phrase in a foreign language, this possibly could be the worst to know.
My second trip, I was better prepared. I learned three "survival phrases":
sumimasen - "I'm sorry/excuse me" hanashimasen - "I don't speak" wakarimasen - "I don't know / I don't understand"
These are great phrases to know individually, but even more powerful strung all together, to emphasize that you will begin speaking English, but at least with good reason (and perhaps a bit of irony.)
I've been to Japan many times since, and have picked up more of the language. When travelling to Japan, or anywhere for that matter, it is important to "pack light". I'll be gone for two weeks, but all I bring is a laptop bag and one carry-on piece of luggage.
I went on a trip to Prague (Czech Republic) with a female co-worker who brought FOUR pieces of luggage. One was just for shoes. Another piece was just for hair styling gel, make-up, face creams and finger nail polish. Today, the rules are different, and the TSA allows only a single quart-size plastic bag containing little jars of 3 ounces or less of liquids or gels. I didn't have any "quart-size" bags, so I used a smaller sandwich-size bag.
What does all this have to do with storage? I've helped many clients move data centers, and this involves moving their servers, their networks, and their storage. Servers and Networks are easy to move, but storage presents some challenges. In many cases, the entire company is shut down, the storage is moved, and then the company is operational again. Needless to say, it is best to do this over a weekend.
I tell clients to "pack light" and figure out what data they really need in the move. What do you really need to operate your business? Bring just that, the rest can arrive later.
This same concept applies for Business Continuity and Disaster Recovery planning. What do you really need after a disaster occurs? Can you run your business for a few weeks on that data, until the rest of the data is restored? If you can't run your entire business on that data, can you run your most important parts of your business?
If you run a bank, perhaps keeping your ATM cash machines running is more important than making out new loans. In Japan, if a bank has any outages that impact their ATM machines, they put out a full page advertisement in the local papers to apologize for the inconvenience.
Business Continuity is one of the nine "Infrastructure Solutions" that IBM can help clients with. If you are interested in learning more on how IBM can help you with your Business Continuity, click here.
Are you covering the business impact of the internet failure across Asia, the Middle East and North Africa? The outage has brought business in those regions to a standstill. This disaster shines a direct spotlight on the vulnerability of technology and serves as a reminder of the ever increasing importance of protecting business critical information.
Disaster recovery needs to be a critical element of every technology plan. We don’t yet know the financial impact of this wide spread internet failure, but the companies with disaster recovery plans in place, were likely able to failover their entire systems to servers based in other regions of the world.
When I first heard of this outage, I am thinking, so a few million people don't have access to FaceBook and YouTube, what's the big deal? We in the U.S.A. are in the middle of a [Hollywood writer's strike] and don't have fresh new television sitcoms to watch! Yahoo News relays the typical government's response:[Egypt asks to stop film, MP3 downloads during Internet outage], presumably so that real business can take priority over what little bandwidth is still operational. Fellow IBM blogger "Turbo" Todd Watson pokes fun at this, in his post[Could Someone Please Get King Tutankhamun On The Phone?].Like us suffering here in America, perhaps our brothers and sisters in Egypt and India may getre-acquainted with the joys of reading books.
However, the [Internet Traffic Report-Asia] shows how this impacted various locations including: Shanghai, Mumbai, Tokyo, Tehran, and Singapore. In some cases, you have big delays in IP traffic, in other cases, complete packet loss, depending on where each country lies on the["axis of evil"].This is not something just affecting a few isolated areas, the impact is indeed worldwide. This would be a goodtime to talk about how computer signals are actually sent.
DWDM takes up to 80 independent signals, converts each to a different color of light, and sends all the colors down a single strand of glass fiber. At the receiving end, the colors are split off by a prism,and each color is converted back to its original electrical signal.
Similar DWDM, but only eight signals are sent over the glass fiber. This is generally cheaper, becauseyou don't need highly tuned lasers.
Wikipedia has a good article on [Submarine Communications Cable],including a discussion on how repairs are made when they get damaged or broken.It is important to remember that lost connectivity doesn't mean lost data, just lack of access to the data. Thedata is still there, you just can't get to it right now. For some businesses, that could be disruptive to actualoperations. In other cases, it means that backups or disk mirroring is suspended, so that you only have yourlocal copies of data until connectivity is resumed.
When two cables in the Mediterranean were severed last week, it was put down to a mishap with a stray anchor.
Now a third cable has been cut, this time near Dubai. That, along with new evidence that ships' anchors are not to blame, has sparked theories about more sinister forces that could be at work.
For all the power of modern computing and satellites, most of the world's communications still rely on submarine cables to cross oceans.
It gets weirder. In his blog Rough Type, Nick Carr's[Who Cut the Cables?] reportsnow a fourth cable has been cut, in a different location than the other two cable locations. If the people cuttingthe cables are looking to see how much impact this would have, they will probably be disappointed. Nick Carrrelates how resilient the whole infrastructure turned out to be:
Though India initially lost as much as half of its Internet capacity on Wednesday, traffic was quickly rerouted and by the weekend the country was reported to have regained 90% of its usual capacity. The outage also reveals that the effects of such outages are anything but neutral; they vary widely depending on the size and resources of the user.
Outsourcing firms, such as Infosys and Wipro, and US companies with significant back-office and research and development operations in India, such as IBM and Intel, said they were still trying to asses how their operations had been impacted, if at all.
Whether it is man-made or natural disaster, every business should have a business continuity plan. If you don't have one, or haven't evaluated it in a while, perhaps now is a good time to do that. IBM can help.
Rich Bourdeau has written a nice article on InfoStor titled [Software as a Service (SaaS) meets Storage]. Last year, IBM acquired Arsenal Digital, and he mentions both in this article.It is interesting how this has evolved over the years.
Rent warehouse space for tapes
I remember when various companies offered remote storage for tapes. These would be temperature and humidity-controlledrooms, with access lists on who could bring tapes in, who could take tapes out, and so on. In the event of thedisaster, someone would collect the appropriate tapes and take them to a recovery site location.
Rent online/nearline storage from a Storage Service Provider (SSP)
SSPs rented storage space on disk, or provided automated tape libraries that could be written to. With tapes being ejected and stored in temperature/humidity-controlled vaults. Electronic vaulting eliminates a lot of theissues with cartridge handling and transportation, is more secure, and faster. Rented disk space, based on a Gigabytes-per-month rate, could be used for whatever the customer wanted. If these were for backups or archive,then the customer has to have their own software, to do their own processing at their own location, sending the data to the remote storage as appropriate, and manage their own administration.
Backup-as-a-Service and Archive-as-a-Service
We are now seeing the SaaS model applied to mundane and routine storage management tasks. New providers can offerthe software to send backups, the disk to write them to, and as needed the tape libraries and cartridges to rollover when the disk space is full. Disk capacity can be sized so that the most recent backups are on immediately accessible for fast recovery.
The same concept can be applied to archives. The key difference between a backup and an archive is that backups areversion-based. You might keep three versions of a backup, the most recent, and two older copies, in case something is wrong with the most recent copy, you can go back to older copies. This could be from undetected corruption of the data itself, or problems with the disk or tape media. An archive, on the other hand, is time-based. You want this data to be kept for a specific period of time, based on an event or fixed period of years.
Since BaaS and AaaS providers know what the data is, have some idea of the policies and usage patterns will be, can then optimize a storage solution that best meets service level agreements.
In explaining the word "archive" we came up with two separate Japanese words. One was "katazukeru", and the other was "shimau". If you are clearing the dinner plates from the table after your meal, for example, it could be done for two reasons. Both words mean "to put away", but the motivation that drives this activity changes the word usage. The first reason, katazukeru, is because the table is important, you need the table to be empty or less cluttered to use it for something else, perhaps play some card game, work on arts and craft, or pay your bills. The second reason, shimau, is because the plates are important, perhaps they are your best tableware, used only for holidays or special occasions only, and you don't want to risk having them broken. As it turns out, IBM supports both senses of the word archive. We offer "space management" when the space on the table, (or disk or database), is more important, so older low-access data can be moved off to less expensive disk or tape. We also offer "data retention" where the data itself is valuable, and must be kept on WORM or non-erasable, non-rewriteable storage to meet business or government regulatory compliance.
The process of archiving your data from primary disk to alternate storage media can satisfy both motivations.
IBM offers software specifically to help with this archival process.For email archive, IBM offers [IBM CommonStore] for Lotus Domino and MicrosoftExchange. For database archive, including support for various ERP and CRM applications, IBM offers [IBM Optim] from the acquisition of Princeton Softech.
The problems occur when companies, under the excuse of simplification or consolidation, feel they can just usetheir backups as archives. They are taking daily backups of their email repositories and databases, and keepingthese for seven to ten years. But what happens when their legal e-discovery team needs to find all emails or database records related to a particular situation, an employee, client or account? Good luck! Most backupsare not indexed for this purpose, so storage admins are stuck restoring many different backups to temporary storage and combing through the files in hopes to find the right data.
Backups are intended for operational recovery of data that is lost or corrupted as a result of hardware failures, application defects, or human error. Disk mirroring or remote replication might help with hardware failures, but any logical deletion or corruption of data is immediately duplicated, so it is not a complete solution. FlashCopy or Snapshot point-in-time copies are useful to go back a short time to recover from logical failures, but since they are usually on the same hardware as the original copies, may not protect against hardware failures. And then there's tape, and while many people malign tape as a backup storage choice, 71 percent of customers send backups to tape, according to a 2007 Forrester Research report.
Backups often aren't viable unless restored to the same hardware platform, with the same operating system and application software to make sense of the ones and zeros. For this reason, people typically only keep two to five backup versions, for no more than 30 days, to support operational recovery scenarios. If you make updatesto your hardware, OS or application software, be sure to remember to take fresh new backups, as the old backupsmay no longer apply.
Archives are different. Often, these are copies that have been "hardened" or "fossilized" so that they make sense even if the original hardware, OS or application software is unavailable. They might be indexed so that they can be searched, so that you only have to retrieve exactly the data you are looking for. Finally, they are often stored with "rendering tools" that are able to display the data using your standard web browser, eliminating the need to have a fully working application environment.
Take any backup you might have from five years ago and try to retrieve the information. Can you do it? This might be a real eye-opener. You might have inherited this backup-as-also-archive approach from someone else, and are trying to figure out what to do differently that makes more sense. Call IBM, we can help.
Well, it is Halloween back in the USA. I am in Seoul Korea this week, so it is already Thursday, November 1st here, but thought I would comment on Colin Barker's piece in ZDnet titled[SNW offers the frights].The article starts out with an oversimplification:
The storage industry is enjoying a boom currently thanks to the requirement for IT managers to keep everything. With the possibility of being sued any time by any company for no good reason at all, everyone is keeping everything, or at least all their data. Result? Loads and loads more kit being bought to the benefit of EMC, IBM, HP and every other supplier with any kind of storage product.
While its true that IBM System Storage grew yet again in 3Q07, exceeding our own internal business model, I would not call this an overall "boom" for the storage industry. While companies are growing in "TB capacity" by 30-50%, this translates only to single digit growth in terms of "Dollar revenues". This is because we continue to make storage with declining dollar-per-GB.
One should not confuse what people do with what people are required to do. I am not a lawyer, but most regulations pertaining to storage of information state that certain records need to be kept for a set amount of time, either a fixed period of years, or based on some event. For example, broker/dealers need to keep emails of their clients for six years after the client closes their brokerage account. After those six years, the records can be destroyed.
Unfortunately, many IT managers look at the laws and come up with the simplest solution: keep everything forever. While this might meet the regulators audit requirements, it does expose their employer to subpoenas for data that should have been deleted, and may not be very cost-effective.
The alternative for many IT managers involves having to leave their comfort zone, and talk to their legal counsel, the lines of business, and try to classify their data, determine a set of policies, and inact some forms of enforcement. This is perhaps the "scary" part of the storage of information, it has grown outside the walls of IT, forcing IT managers to interact with the rest of the business to get their jobs done.
Compliance is the only game in town and that is most certainly where the money is.
Anytime an analyst tells you that something is the "only game in town", they are usually wrong. In this case, IBM has had great success in other areas that are not compliance-related. For example, digital video surveillance (DVS) is being used not only to help reduce shoplifting, but also to help identify patterns in customers perusing through aisles and window-shopping. Identifying what people are interested in has proven effective in moving product displays around to better attract buyers and motivate them to make purchases.
Take, the keynote from Andy Monshaw, general manager of IBM storage, and thus a man who is very much in a position to know. He spent his allotted 30 minutes, or whatever, listing all the security, compliance, threats and related issues that are currently making the jobs of most IT manager a cause for concern. Now, there is an argument that suggests that it is absolutely the right thing to do to frighten IT managers into sorting out their issues. They need shaking up say some. Especially analysts.
I helped develop the content of Andy's SNW presentation, working with his speech writers and graphic artists to make a consistent and coherent message fit in the 25 minutes he was given. The challenge with SNW is that we needed to make this presentation applicable across the entire storage industry, without sounding like an infomercial for IBM offerings.
Some people have compared the storage to the "insurance industry", claiming that backups, remote disk mirroring, continuous data protection and other storage related features are costs that can be compared to insurance you pay to protect your home, business, and other assets. You hope you never have to use it, and complain how much it costs, but when bad things happen, you hope it is the best money can buy.
Unlike Y2K, which was a one-time event that had a specific date of occurrence, the threats and risks mentioned by Andy in his presentation may never happen at all, or in other cases, may happen more than once, without knowing when or where. For the sake of your shareholders, and your stakeholders, it is best to be prepared for these possibilities.
The counter argument says that IT companies just smell the money.
Is this a counter argument? Can IBM not both help customers mitigate their risks, and at the same time, turn a profit? Trust me, you do not want to do business with any storage vendor that is not interested in making a profit. The better ones have incorporated addressing client's most pressing challenges into their strategy. I gave a quick summary of IBM's strategy last August in [Day 1 Storage Symposium].
Helping our clients mitigate risks is just one of IBM's core strengths. If you want to learn more, contact your local IBM Business Partner or storage rep.
I survived my first day at SNW Spring 2007.This is my first time at SNW, but it is very much like many of the other conferences I have been to.It officially started Monday morning with pre-conferencetutorials and primer break-outsessions that covered storage fundamentals, but I didn't arrive until late Monday night due to highwind conditions at the Phoenix airport that delayed my travel.
Tuesday started out with main tent sessions. Ron Milton, VP of ComputerWorld that puts on this conference,and Vincent Franceschini, Chairman of the Board for SNIA, kicked off the event.It didn't take them long to get into the alphabet soup: ILM, ITIL, SMI-S, XAM, IMA, MMA, DDF,MF, DMF, IPSF, SSIF, and SRM.Several hundred people had "voting devices" so that they could participate in "informal" surveys.
Q1. What was the greatest need?
37% Storage Resource Management (SRM) tools
19% Storage Virtualization
19% Information Lifecycle Management (ILM)
14% Integration with other management tools
11% Compliance storage for regulations
Q2. What are people doing to address storage infrastructure complexity?
33% Deploying new SRM and SAN management tools
26% Adopting "Storage as a Service" methodology
22% Deploying new storage virtualization technologies
8% Hiring more staff
9% (complexity was not an issue)
The first keynote speaker was Cora Carmody, CIO of SAIC. In the late 1980s and early 1990s, I did a lot of work with SAIC here in San Diego, and so IBM sent me to San Diego quite frequentlyfor face-to-face meetings with them. Her talk was cryptically titled "Jumbo Shrimp, InformationManagement, and the Mark of the Beast." Coming up with good titles is important. Some of herkey points:
"Information management" was as much an oxymoron as "jumbo shrimp" or "military intelligence".(SAIC is a general contractor for the US Military, so this was especially funny).
Computer data needs both "ownership" and "stewardship".
Gartner analyst reports that 50% of digital information for a business resides in personal files onindividual PCs.
PAN-StaRRs project is ingesting 10TB per week of astronomical data.
TeraTEXT(R) project is a non-relational database that supports a large mix of structured and unstructured content.
The next "Y2K" crisis for the USA is changing from 3-digit to 4-digit area codes for our telephone numbers.
Battery size and life have not advanced as fast as we need
There has been little progress in "User Interface" ease of use
Formats and standards are picked for the most part by the winning vendors, and it is the silence of themarketplace that lets them get away with this.
We are overly reliant on an inherently insecure medium.
The "mark of the beast" refers to exciting new technologies based on "presence awareness". For example,some hotels now are able to check you into the hotel as you drive up in your car, based on your car's licenseplate. Some 24-hour gyms use your fingerprint as your entry credentials, eliminating the need to staff peopleat the front desk.
IBM's own Barry Rudolph, presented "Storage in an Age of Inconvenient Truths", dressed up like Oscar-winner andformer USA Vice President Al Gore. Barry's focus was on the growingconcern of over environmental Power and Cooling issues in the data center. According to IDC, the cost of power and cooling an individual server, over its lifetime, now exceeds its acquisition cost. Storage devices are not as bad as servers in this regard. Data centers now consume 1.2% of the worlds energy.
Over lunch, I heard Tony Asaro from ESG present "The Need for Highly Virtualized Storage Systems withina Virtualized Data Center." His concern is that there is still a "heavy touch" required to manage storage.Without virtualization, your data center is less than the sum of its parts. Although IBM has been doingstorage virtualization since 1974, Tony mentioned that most storage vendors were "late to the party".He argues that "internal virtualization" inside storage arrays is not enough, you need "external virtualization"(like the IBM System Storage SAN Volume Controller) to virtualize your entire infrastructure.What storage administrators would like is for storage to have consumer levels of "ease of use", and today'snon-virtualized storage environments are nowhere near that.
"The great advantage [the telephone] possesses over every other form of electrical apparatus consists in the fact that it requires no skill to operate the instrument." - Alexander Graham Bell, 1878
I attended a few break-out sessions in the afternoon.
Ralph presented "Crisis of Capacity" which covered the drastic actions he had to take to handle power and coolingin their expanding data center during their summer months, where temperatures peak up to 105 degrees. This included creating "hot" and "cold" aisles onhis raised floor by re-organizing the perforated floor tiles, and doing a better job standardizing how cables areconnected to the back of racks and up through the ceiling to maximize airflow. An amp-meter on each power strip was used to measure the powerused at each rack, which allowed them to better prioritize their efforts. Their Air Conditioning unit was only 12inches from the concrete floor, and raising it to 18 inches greatly reduced noise and vibration. Adding a second AC unit made a world of difference. Finally, they eliminatedKVMs, because people who use KVMs break other parts of thedata center. His rule of thumb: the cooling requirements will be 50% of the rated power requirements for equipment.
Terry Yoshi, Intel internal IT department, as a member of the SNIA's end user council
Terry presented "Taming the SAN Complexity". The problem with "complexity" as a concept is that it is very subjective, difficult to quantify, and therefore difficult to manage. He presented complexity in four areas:Organizational structure of the company as a whole; skill sets required of the IT staff; business process andprocedures; and technology. Dealing with complexity is a battle between Old School (because we've always doneit this way) and New School (because it is new and different technology). Storage Area Networks are inherentlya "shared resource", and the increased complexity is a direct result of the low reliability of the componentsand devices it is composed of. People should focus on the "Total Cost of Ownership" (TCO) for a SAN, and not just the initial acquisitionprice of SAN gear.He was not a fan of the "dual/multiple" vendor strategy that many companies employto reduce costs. His suggestion that things should be tried out first on your "test SAN" caused some chuckles,as few have such a thing. Finally, he suggested not only documenting "Best Practices" and "Best Known Methods"but also things that have been found not to work, his do-not-try-this-at-home list.
Tony Antony, Cisco marketing manager for Optical products
This was an overview of the technologies available for long distance connections for disaster recovery,business continuity, and resilience. He covered three levels.
IP - Fibre Channel of IP (FCIP) offers the greatest "global" distance but forces people into asynchronous mirroring.
SONET/SDH - SONET is what we call it in the USA, and SDH is what it is called in other countries. This provides state-to-state or "out-of-region" distances, which is ideal to meet certain government regulations for homeland defense. He suggests this is offered when dark fiber or DWDM is not available.
DWDM/CWDM - this is using a prism to run multiple colors of light through a single fiber optic cable. CWDM ischeaper, but only handles 8 signals per cable. DWDM can handle 32 to 160 signals per cable, but is more expensive.
His rule of thumb: one buffer credit for every kilometer at 2Gbps speed (for every 2km at 1Gbps).
The day ended at the "Expo". I hung out at the IBM booth to help answer questions and network with others.
Last week, I opined that Monday's IDC announcement "IBM #1 in combined disk and tape storage hardwaresales for 2006" was in part because of a resurgence of interest in tape, with four specific examples. There was a lot of reaction and reflection fromboth sides.
On the one side...
EMC blogger Mark Twomey at Storagezilla admits that perhapsTape Isn't Dead after all,is perhaps the best place to put long-term archive data, but not for backup? EMC's "creative marketing types" put out this Fun With Tape video that I found amusing. (It asks for a first name,last name, and e-mail address, which are then embedded into the resulting video itself, and perhaps forwarded to your nearest EMC sales rep, so answer according to your wishes for privacy).
The "mummy wrapped in tape media" seems to be a common theme, and shows up again in LiveVault'svideo with John Cleese, which makes the same argument asthe EMC video above, namely: switch your backups from tape to disk because we are a disk-only vendor.
... and on the other side
JWT over at DrunkenData asks Which is greener, disk or tape?Tape is, of course, by a long shot, and an essential part of IBM's Big Green initiative, a project to invest$1US Billion dollars per year for data centers to be more efficient for power and cooling.
Sun/StorageTek blogger Randy Chalfant questions the Death of Tape, and argues thatdisk-only solutions suffer from atrophy.The results he posts from a survey of 200 customers are similar to those we've seen with customers using IBM TotalStorage Productivity Center, our software to help evaluate data usage, and identify misuse, in your data center.
To my readers in the USA, United Kingdom, Ireland, South Africa, China and Japan, and a few other countries, Happy Father's Day!
I didn't really have a theme this week, still recovering from jet-lag from my travels through Japan, Australia, China.
Gary Diskman has an amusing blog entry about a Funny disaster recovery job posting. It is not clear if he is being completely tongue-in-cheek, or a bit cynical. However, it rings true that you get what you measure, and some managers look for easy metrics, even if there are unintended consequences.
Western medicine works this way. Rather than paying your doctor to keep you healthy, you pay him per visit, to get refills on prescriptions, check-ups on medical conditions, surgeries and so on. While Eastern medicine is focused on keeping people healthy, Western medicine profits more from resolving "situations".
I have seen similar situations on the "health" of the data center. In one case, the admins were measured on how quickly they bring back up their web-servers after a crash. They had this process down to a science, because they were measured on how quickly they resolved the situation. I suggested switching from Windows to Linux, a much more reliable operating system for web-serving, and showed examples of web-servers running Linux that have been up for 1000 days or more. Management changed the metrics to "average up-time in days" and magically the re-boots all but disappeared, thanks to Linux, but also thanks in part to shifting the incentive structure. Perhaps some of those earlier situations were "artificially created"?
Back in the 1980s, I was working on a small software project that was about 5000 lines of code. In those days, testers were measured by the number of "successful" testcases that ran without incident. Testcases that uncovered an error were labeled as "failures" to be re-run after the developers fixed the code. When I declared my code ready for test, the test team ran 110 testcases, all successfully, and they were all rewarded for meeting their schedule. I, on the other hand, did not accept these results, met with them and told them I would give them $100 each if they could find a bug in my code in the next week. Nobody writes 5000 lines of code without some error along the way, not even me. (As one author put it, more people have left earth's gravity to orbit the planet than have written perfect code that did not require subsequent review or testing. It's so true. Good software is difficult to write.)
The test team accepted the challenge, and found 6 problems, more than I expected, but at least I felt more confident of the code quality after fixing these. As I suspected, the unintended consequence of counting "successful" testcases was that testers would write the most simple, basic, least-likely-to-challenge-boundaries testcases to ensure they meet their numbers. My experiment was costly to me, but more importantly was a wake-up call for the test management, and they realized they needed to re-evaluate their test procedures, metrics and terminology. This was a long time ago, and I am glad to see that the overall "software engineering" practice has matured much over the past 20 years.
So, my advice is to determine metrics that have the intended consequences you want, while avoiding any negative unintented consequences that might undermine your eventual success. People will quickly figure out how to maximize the results, and if you can align their goals to company goals, then everybody benefits.
Well, I'll be blogging from Mexico next week (yes, it is a business trip!). Enjoy the weekend.
This week and next I am touring Asia, meeting with IBM Business Partners and sales repsabout our July 10 announcements.
Clark Hodge might want to figure out where I am, given the nuclearreactor shutdowns from an earthquake in Japan. His theory is that you can follow my whereabouts just by following the news of major power outages throughout the world.
So I thought this would be a good week to cover the topic of Business Continuity, which includes disaster recovery planning. When making Business Continuity plans, I find it best to work backwards. Think of the scenarios that wouldrequire such recovery actions to take place, then figure out what you need to have at hand to perform the recovery, and then work out the tasks and processes to make sure those things are created and available when and where needed.
I will use my IBM Thinkpad T60 as an example of how this works. Last week, I was among several speakers making presentations to an audience in Denver, and this involved carrying my laptop from the back of the room, up to the front of the room, several times. When I got my new T60 laptop a year ago, it specifically stated NOT to carry the laptop while the disk drive was spinning, to avoid vibrations and gyroscopic effects. It suggested always putting the laptop in standby, hibernate or shutdown mode, prior to transportation, but I haven't gotten yet in the habit of doing this. After enough trips back and forth, I had somehow corrupted my C: drive. It wasn't a complete corruption, I could still use Microsoft PowerPoint to show my slides, but other things failed, sometimes the fatal BSOD and other times less drastically. Perhaps the biggest annoyance was that I lost a few critical DLL files needed for my VPN software to connect to IBM networks, so I was unable to download or access e-mail or files inside IBM's firewall.
Fortunately, I had planned for this scenario, and was able to recover my laptop myself, which is important when you are on the road and your help desk is thousands of miles away. (In theory, I am now thousands of miles closer to our help desk folks in India and China, but perhaps further away from those in Brazil.) Not being able to respond to e-mail for two days was one thing, but no access for two weeks would have been a disaster! The good news: My system was up and running before leaving for the trip I am on now to Asia.
Following my three-step process, here's how this looks:
Step 1: Identify the scenario
In this case, my scenario is that the file system the runs my operating system is corrupted, but my drive does not have hardware problems. Running PC-Doctor confirmed the hardware was operating correctly. This can happen in a variety of ways, from errant application software upgrades, malicious viruses, or in my case, picking up your laptop and carrying it across the room while the disk drive is spinning.
Step 2: Figure out what you need at hand
All I needed to do was repair or reload my file sytem. "Easier said than done!" you are probably thinking. Many people use IBM Tivoli Storage Manager (TSM) to back up their application settings and data. Corporate include/exclude lists avoid backing up the same Windows files from everyone's machines. This is great for those who sit at the same desk, in the same building, and would be given a new machine with Windows pre-installed as the start of their recovery process. If on the other hand you are traveling, and can't access your VPN to reach your TSM server, you have to do something else. This is often called "Bare Metal Restore" or "Bare Machine Recovery", BMR for short in both cases.
I carry with me on business trips bootable rescue compact discs, DVDs of full system backup of my Windows operating system, and my most critical files needed for each specific trip on a separate USB key. So, while I am on the road, I can re-install Windows, recover my applications, and copy over just the files I need to continue on my trip, and then I can do a more thorough recovery back in the office upon return.
Step 3: Determine the tasks and processes
In addition to backing up with IBM TSM, I also use IBM Thinkvantage Rescue and Recovery to make local backups. IBM Rescue and Recovery is provided with IBM Thinkpad systems, and allows me to backup my entire system to an external 320GB USB drive that I can leave behind in Tucson, as well as create bootable recovery CD and DVDs that I can carry with me while traveling.
The problem most people have with a full system backup is that their data changes so frequently, they would have to take backups too often, or recover "very old" data. Most Windows systems are pre-formatted as one huge C: drive that mixes programs and data together. However, I follow best practice, separating programs from data. My C: drive contains the Windows operating system, along with key applications, and the essential settings needed to make them run. My D: drive contains all my data. This has the advantage that I only have to backup my C: drive, and this fits nicely on two DVDs. Since I don't change my operating system or programs that often, and monthly or quarterly backup is frequent enough.
In my situation in Denver, only my C: drive was corrupted, so all of my data on D: drive was safe and unaffected.
When it comes to Business Continuity, it is important to prioritize what will allow you to continue doing business, and what resources you need to make that happen. The above concepts apply from laptops to mainframes. If you need help creating or updating your Business Continuity plan, give IBM a call.
Continuing this week's theme on Business Continuity, I thought I would explore more on the identification of scenarios to help drive appropriate planning. As I mentioned in my last post, this should be done first.
A recent post in Anecdote talks about the long list of cognitive biases which affect business decision making. This list is a good explanation of why so many people have a difficult time identifying appropriate recovery scenarios as the basis for Business Continuity planning. Their "cognitive biases" get in the way.
Again, using my IBM Thinkpad T60 laptop as an example, here are a variety of different scenarios:
Corrupted File System
Some file systems are more fragile than others. If your NTFS file system gets corrupted, you might be able to run
CHKDSK C: /F
but this just puts damaged blocks into dummy files, it doesn't really repair your files back to their pre-damage level.All kinds of things can damage the file system, including viruses, software defects, and user error.
I keep my programs and data in separate file systems. C: has my Windows operating system and applications, and D: holds my pure data. If one file system is corrupted, the other one might be in tact, mitigating the risk.
Hard Disk Crash
Hopefully, you will have temporary read/write errors to provide warning prior to a complete failure. In theory, if I kept a spare hard disk in my laptop bag, I could swap out the bad drive with the good drive. I don't have that. The three times that I have had a disk failure all occurred while I was in Tucson.
Instead, I keep the few files I need for my trip on a separate USB key, and carry bootable Live CD, which allows you to boot entirely from CDrom drive, either to run applications, or perform rescue operations.
The latest one that I am trying out is Ubuntu Linux, which has OpenOffice 2.2 that can read/write PowerPoint, Word, and Excel spreadsheets; Firefox web browser; Gimp graphics software; and a variety of other applications, all in a 700MB CDrom image. I even have been able to get Wireless (Wi-Fi) working with it, and the process to create your own customized Live CD with the your own application packages is fairly straightforward. Combined with a writeable USB key, you can actually get work done this way. Special thanks to IBM blogger Bob Sutor for pointing me to this.
(If you have a DVD-RAM drive, there are bigger Live CDs from SUSE and RedHat Fedora that provide even more applications)
Laptop Shell Failure
This might catch some people by surprise. I have had the keyboard, LCD screen, or some essential port/plug fail on my laptop. The disk drive and CDrom drive work fine, but unless you have another "laptop" to stick them into, they don't help you recover. This can also happen if the motherboard fails, or the battery is unable to hold a charge.
IBM provides a 24-hour turn around fix. Basically, IBM sends me a laptop shell, no drive, no CDrom, with instructions to move the disk drive and CDrom drive from your broken shell, to the new shell, then send the bad shell back in the same shipping box.
Here, again, I am thankful that I keep my key files on an USB key. Often I travel with other IBMers, and can borrow their laptop to make presentations, check my e-mail, or other work, until I can get my replacement shell. In you are travelling outside the US, you might be able to move your disk drive into a colleague's laptop, access the data, copy it to your USB key or burn a copy on CD or DVD.
In a data center, many outages are really "failures to access data", but the data is safe. For example, power outages, network outages, and so on, can prevent people from using their IT systems, but the data is safe when these are re-established.
At times, I have been temporarily separated from my laptop. Three examples:
A higher level executive had technical difficulties with his laptop, and usurped mine instead.
A colleague forgot his power supply for his laptop, and borrowed my laptop instead. (I wish there were a standard for laptop power plug connectors)
Customs agents confiscate your laptop, give you a receipt, and eventually you get it back.
In all cases, I was glad that no "recovery" was required, and that the few files I needed were on my USB key. A few times, I was able to get by on the machines available at the nearest Internet Cafe, in the meantime.
With some imagination, you can recognize that this scenario is similar to the previous one for laptop shell failure.Here is a good example that you can identify different scenarios, and then later discover they have similar properties in terms of recovery, and can be treated as one.
Laptops are stolen every day. Luckily, I've only had this happen twice to me in my career at IBM, and I managed to get a replacement soon enough. The key lesson here is to keep your USB key and recovery media in separate luggage.I know it is more convenient to keep all computer-related stuff in one place, but a thief is going to take your whole laptop bag, to make sure that all cables and power supplies are included, and is not going to leave anything behind. That would just slow them down.
In each case, some brainstorming, or personal experience, can help identify scenarios, identify what makes them unique from a recovery perspective, and plan accordingly. If you looking to create or upgrade your Business Continuity plan, give IBM a call, we can help!
The blogosphere has quieted down a bit over the two papers on MTBF estimates for Disk Drive Modules (DDM).One article on SearchStorage.com by Arun Taneja asksIs RAID passé? Disk capacity is growing at a faster rate than DDM reliability. During the hours to rebuild a DDM, companies are at risk of additional failures that could require recovery from a copy, or result in data loss, depending on how well your Business Continuity (BC) plan is written and followed.
... The problem with that is that it's the DISK ARRAY that determines when a drive has failed an starts the rebuild process. That IS under the control of IBM, specifically the controller. But more importantly, it effects my risk of data loss.
As I see it, my risk of data loss with RAID-5 is influenced by two main factors. 1 - The drive replacement rate and 2 - The rebuild time (which to a great extent is a function of the drive size) both of which IBM has some control over.
So, I think that the question in my mind is, what's the tipping point? Where does the risk of using RAID-5 protection exceed what I'm willing to accept, and I need to move to some other protection mechanism like RAID-6? Is it when the rebuild times exceed 12 hours? 24 hours? 48 hours?
Also, I wonder why IBM isn't publishing some information to help me make these kinds of decisions?
Oh, dear - while Tony doesn’t seem to be parrying vigorously (as Seagate, Hitachi, and Chunk were doing), his contribution sounds more like IBM marketing than the kind of detailed, technical response one might have hoped for
... well, he *is* a manager, and a marketing one at that, so perhaps we shouldn’t expect more).
Both are fair comments. Disk arrays do run microcode to assist or perform the RAID function, detect failures and start the rebuild process, and so clever designs to support spare disks, process the rebuild quickly, and so on, can differentiate one vendor's offering from another.
On the issue of what does IBM provide to help its clients make the right decisions for their environments, Jon William Toigo at DrunkenData points his readers to IBM's Business Continuity Self-Assessment tool. In normal data center conditions, DDMs will fail, and a Business Continuity plan shouldbe written and developed to handle this fact. Using 2-site and 3-site mirroring, complemented with versions of tape backups, can help address some of these concerns and mitigate some of the risks involved with using disk systems.
For those who want a more technical answer, IBM has just published a series of IBM Redbooks.
Each client's situation is different, so no simple answer is possible. However, IBM does have a lot of experience in this area, and would be glad to help you write or update your existing Business Continuity plan.