Continuing this week's theme on Storage Area Networks, today I thought I would talkabout the various terms we use for our equipment.
One area of confusion are the adjectives "entry-level", "midrange" and "ent If you are asking yourself "which size is right for my company?" or "is my company big enoughfor a director?" you are asking the wrong questions! Instead, determine a SAN configurationthat meets your workload, and then decide the components for that design. McData coined a phrase called "core/edge" design that is considered today as "Best Practice" throughout the industry.A good write-up can be found here at SearchStorage.com. Basically, you put your big beefy "core" directors in the center of the room, and then surround it with midrange switches, that then these connect to "edge" switches, that then connect to the servers and storage near them. As you grow, this design can easilyscale to grow with you. So, if you need help implementing a SAN for the first time, or upgrading the one you have,call IBM, we can help!
If you are asking yourself "which size is right for my company?" or "is my company big enoughfor a director?" you are asking the wrong questions! Instead, determine a SAN configurationthat meets your workload, and then decide the components for that design.
McData coined a phrase called "core/edge" design that is considered today as "Best Practice" throughout the industry.A good write-up can be found here at SearchStorage.com. Basically, you put your big beefy "core" directors in the center of the room, and then surround it with midrange switches, that then these connect to "edge" switches, that then connect to the servers and storage near them. As you grow, this design can easilyscale to grow with you.
So, if you need help implementing a SAN for the first time, or upgrading the one you have,call IBM, we can help!Read More]
Last week, Paul Weinberg of eChannelLine.com asks Is this the year of the SAN (again)?So, I thought this week I would cover my thoughts and opinions on storage networking. We oftenfocus on servers or storage devices, and forget that the network in between is an entire worldon itself.
I believe Mr. Weinberg is basing this on the idea that in 2007, over 50 percent of disk will beattached over SAN, edging out the alternative: Direct Attached Storage (DAS). But perhaps 50 percentis the wrong number to focus on. In 2007, The United Nations estimates thatcities will surpass rural areas, with just over 50 percent of theworld's population. Does that make this the "Year of the City"? Of course not.
Instead, I prefer to use the methodology that Malcolm Gladwell uses in his book, The Tipping Point.(I have read this book and highly recommend it!)Gladwell indicates that the tipping point happens at the start of the epidemic, not when it is half over.Isn't it better to celebrate the sweet 16 debutante ball when young ladies have completed their years of training and preparation, and are ready to be introduced to the rest of the world, rather than after they are thirty-something, married with children.
Let's explore some of the history. Stuart Kendric has a nice 7-page summary on theHistory & Plumbing of SANs.
IBM announced the first SAN technology calledEnterprise Systems Connection (ESCON) way back in September 1990. This allowed multiplemainframe servers to connect to multiple storage systems over equipment called "ESCON Directors" that directedtraffic from point A to point B. Before this, mainframes sent "ChannelCommand Words" or CCWs, across parallel "bus and tag" copper cables. ESCON was serial overfiber optic wiring. SANs solved two problems: first, it reduced the "rat's nest" of cables between many serversand many storage systems, and second, it extended the distance between server and storage device.
For distributed systems running UNIX or Windows, the CCW-equivalent over parallel cables was called Small ComputerSystem Interface (SCSI). The SCSI command had over 1000 command words, so for its Advanced Technology (AT) personal computers (PC AT), IBM introduced a subset of SCSI commands called ATA (Advanced Technology Attachment). ATA drives supportedfewer commands, ran at slower speeds, and were manufactured with a less rigorous process. Today ATA drives are about 55 percent the cost per MB as comparable SCSI drives.
Anyone who has ever opened their PC and found flat ribbon cable with eight or sixteen wires in parallel, can understand that the same issues applied externally. Parallel technologies arelimited to distance and speed, as all the bits have to arrive at the end of the wire at approximately thesame time. Direct attach schemes with every server attaches directly to every storage device were also problematic.Imagine 100 servers connected to 100 storage devices, that would be 10,000 wires!
So, a new technology standard was developed, called Fibre Channel, ratified in 1994.The spelling of "Fibre" was intentionally made different than "Fiber" on purpose. "Fibre" is a protocol thatcan travel over copper or glass wires. "Fiber" represents the glass wiring itself.
Fibre Channel is amazingly versatile. For today's Linux, UNIX and Windows servers, it can carry SCSI commands, and the combination of SCSI over FC is called Fibre Channel Protocol (FCP). For the mainframe servers, it can carry CCW commands. Running CCW over Fibre Channel is called FICON. This convergence allows mainframes and distributed systems to share a common Fibre Channel network, using the same set of switches and directors.
We saw the use of SANs explode in the marketplace over the past 10 years, and then cool down with a series of mergers and acquisitions. Last year, Brocade announced it was acquiring rival McData, so we will be down to two major players, Cisco and Brocade.
So, IMHO, I think we are well past the "Year of the SAN".
Continuing this week's theme of New Year's Resolutions for the data center, today we'll talk about one that people don't always think about on a personal level, that is to hone your tools and skills.
A long time ago, I used to be a regular speaker at the SHARE user group conference. One of the most attended sessions was Sam Golob presenting the latest CBT Tape set of tools. Over time, this large collection of "mainframe shareware" was handed out on 3480 tape cartridges, then on CDs, and finally made downloadable off the web.Sam's main point, which I remember to this day, was that everyone who has a job should figure out what tools they use, keep those tools functioning properly, and learn to use them well.
Later, I took some cooking classes at a culinary school. Among other things, we learned:
This last point hits close to home, as many people like me have too many tools that they do not use often enough to know how to use them well. Do I really need my strawberry corer, garlic press, or a tray designed for the storage and delivery of deviled eggs?
The same could be said about software tools. What tools do you use in your job? Do you feel you know how to take full advantage of their power and capabilities?If you develop software, do you know all the features for your debugging tools? If you develop advertising or marketing materials, do you know all the features of your photo or video editing software? If you manage storage in a data center, do you know all the tools for managing your storage area network (SAN), disk systems, tape libraries, and reporting tools to identify all of your files and databases across your entire IT environment?I would not be surprised if you could replace a whole mess of tools with just one, such as the IBM TotalStorage Productivity Center.Read More]
Wrapping up this week's theme of New Year's Resolutions for the data center, the New York Times argues we should go easy on the resolutions, so I'll conclude with reducing stress. Lighten up! Relax, and try not to take your job so seriously.
(I know you're probably thinking, "That's easy for you to say, Mr. paid
technorati tags: New Years, resolutions, reducing stress, laughter, Tucson Laughter Club, Laughter Yoga, Sun, StorageTek, Kodak, Work/Life Balance, sleep, blogfights, assertive, music, LifeHacker, Live365, Pink Noise[Read More]
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Continuing this week's theme of New Year's Resolutions for the data center, today we'll talk about one that many people make for their own personal lives: staying on a budget.
Often, when faced with a tightening budgets, we try to make more use of what we already have. Tell someone they are only using 10 percent of their brain, and they immediatelybelieve you; but tell them they are only using 30 percent of their storage, and they ask for a whitepaper,magazine article, or clarification on how that percentage is calculated. I actually visiteda customer that was only using6 percent of the storage attached to their Windows servers!
So, to help those of you making data center resolutions to stay on budget, the terms to remember are "Reduce", "Reuse" and "Rec If you are going to keep on a budget, remember that storage today is 30% more expensive than storage next year. That is the average drop in both disk and tape on a dollar-per-MB basis. If there is any way to postpone giving out storage until it is actually needed, you can save a bundle of money. Timing is everything! In the event of a disaster, getting immediate replacement for disk can be very expensive, but if you can wait just two weeks, you can negotiate a better deal. I thought of this while going to the movie theatre yesterday. A "hot dog" and a bottle of water was $8.00, but if you are able to wait two hours and eat after the movie, you can get a much better meal for less. Chances are, you have unused disk capacity spread across all your storage today, but perhaps they are formatted into small LUNs. The SVC can combine the capacity, and let you carve up big LUNs at the sizes you need.This is like taking all those tiny pieces of soap in your shower and forming a new bar of soap, or taking all the crumbs at the bottom of your bread box, and making a new slice of bread. And, the virtual LUNs are dynamically expandable,so give out only the amount they need today, as it is simple to expand them to larger sizes later. When evaluating your use of tape, determine if you are making best use of the tapes you have now, and perhaps a RECYCLE (or reclamation) scheme may be in order. Fewer tapes can save money in many ways, such as reduced storage costs, and reduced courier costs to send the tapes offsite. Tape media can still be 10-20 times less expensive than disk, based on full capacity.
If you are going to keep on a budget, remember that storage today is 30% more expensive than storage next year. That is the average drop in both disk and tape on a dollar-per-MB basis. If there is any way to postpone giving out storage until it is actually needed, you can save a bundle of money. Timing is everything! In the event of a disaster, getting immediate replacement for disk can be very expensive, but if you can wait just two weeks, you can negotiate a better deal. I thought of this while going to the movie theatre yesterday. A "hot dog" and a bottle of water was $8.00, but if you are able to wait two hours and eat after the movie, you can get a much better meal for less.
Chances are, you have unused disk capacity spread across all your storage today, but perhaps they are formatted into small LUNs. The SVC can combine the capacity, and let you carve up big LUNs at the sizes you need.This is like taking all those tiny pieces of soap in your shower and forming a new bar of soap, or taking all the crumbs at the bottom of your bread box, and making a new slice of bread. And, the virtual LUNs are dynamically expandable,so give out only the amount they need today, as it is simple to expand them to larger sizes later.
When evaluating your use of tape, determine if you are making best use of the tapes you have now, and perhaps a RECYCLE (or reclamation) scheme may be in order. Fewer tapes can save money in many ways, such as reduced storage costs, and reduced courier costs to send the tapes offsite. Tape media can still be 10-20 times less expensive than disk, based on full capacity.
Happy New Year!
This year I resolve to be more consistent in my blogging, and my goal is to give you one to five entries per week, every week, based on the advice from Glenn Wolsey, Jennette Banks, and others.On some weeks, I will have a running theme, so rather than super-long entries to cover everything I can think of on a topic, make the entries short and readable. This week is a good time to review last year's "New Year's Resolutions" and to make new ones for 2007. I will discuss actions that companies can adopt for their data centers.
A common resolution is to lose weight, as in this Dilbert comic. Last year, I resolved to lose weight in 2006, and am delighted with myself that I lost eight pounds. When people ask for the secret of my success, I whisper in their ear "Eat less, exercise more." In general, people (and companies) know what to do, but just don't do it, which Pfeffer and Sutton document in their book The Knowing-Doing Gap. In my case, it involved lifestyle change: I exercised at a gym three times per week in Tucson, with a personal trainer, and revamped my diet.
Not everyone subscribes to the "eat less exercise more" philosophy. For example, Ric Watson argues in his blog that you can eat fewer calories, but eat more in actual volume, by choosing the right foods. This brings up the issues of "metrics" that most data centers are familiar with. Last year, I read the book "You: On a Diet" which explains that it is better to focus on "waist reduction" as measured in inches around your mid-section at the belly button, than "weight reduction" as measured in pounds. This year, I resolve to get down to 35 inches by the end of 2007.
The problem with measuring "weight" is that you are weighing bones, muscle and fat. A person can gain ten pounds of muscle, lose ten pounds of fat, and the scale would indicate no progress. The same problem occurs in data centers. How many TB of data do you have? Storage admins can easily tell you, but can they tell how much of this is bone (data needed for operating infrastructure), muscle (data used in daily operations that generates revenue) or fat (obsolete or orphaned data)?
We at IBM often state that "Information Lifecycle Management (ILM)" is more lifestyle change than a "fad diet". Figuring out what data you should capture in the first place, where to place it, when to move it, and when to get rid of it, is more important that just buying different tiers of storage hardware. So, for those looking to make new data center resolutions, I suggest the following actions:
Continuing this week's theme of recap for 2006, I thought it would be good to look back at the various videos made available on the internet.
In his blog, Paul Gillin agrees with Time Magazine's Person of the Year choice of "all of us", those of us who use the World Wide Web to do business or have fun, and to those who contribute to the internet by creating content, such as people who blog or create websites.
So, in continuing my theme this week to recap the best and worst of last year, I list my personal "tech highlights" of 2006.
I am sure there are other triumphs I had throughout the year, but these are the first the come to mind.
'Those who cannot remember the past are condemned to repeat it.'
This last week of 2006 seems like a good time to recap the past year, and review the upcoming new year.That said, a good start is PC World's Top 21 Tech Screwups of 2006.
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For those of us in the northern hemisphere, yesterday was this year's Winter Solstice, representingthe shortest amount of daylight between sunrise and sunset. So today, I thought I would blog on my thoughtsof managing scarcity.
Earlier in my career, I had the pleasure to serve as "administrative assistant" to Nora Denzel for the week at a storage conference. My job was to make her look good at the conference, which if you know Nora, doesn't take much. Later, she left IBM to work at HP, and I gotto hear her speak at a conference, and the one thing that I remember most was her statement that thewhole point of "management" was to manage scarcity, as in not enough money in the budget,not enough people to implement change, or not enough resources to accomplish a task.(Nora, I have no idea where you are today, so if you are reading this, send me a note).
Of course, the flip-side to this is that resources that are in abundance are generallytaken for granted. Priorities are focused on what is most scarce. Let's examine some of theresources involved in an IT storage environment:
This last point brings me back to the concept of food, and I am not talking about doughnuts in the conference room, or pizza while making year-end storage upgrades. I'm talking aboutthe food you work so hard to provide for yourself and your family. The folks at Oxfam came up with a simpleanalogy. If 20 people sit down at your table, representing the world’s population:
Happy Winter Solstice!
technorati tags: IBM, Northern, Hemisphere, Winter, Solstice, Nora+Denzel, Oxfam, scarcity, Linux, UNIX, Windows, TSM, Tivo
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Well, there's little to no chance we'll get snow in Tucson the rest of this year, so I built a snowman out in Second Life. That's my avatar on the right, andI am an eightbar specialist. Eightbar refers to our logo.
This was part of an IBM "Holiday Party" where dozens of IBMers met "in the virtual world" to participate in 3D competitions,I entered the "Build a Snowman" competition, since I am still a beginner at this. This was whatI was able to come up with in 20 minutes that we had to get it done. Why I made mine out of woodwith different colors was so that I could stand out from the crowd. Everyone else used traditionalwhite snowy textures.
Others had a more challenging "Build a Snow Globe" where you have to write scripts to get thelittle snow flakes to move around. This for the advanced builders of our group.
This is still new, emerging technology, but eventually, Second Life and other MMOs could be used to market products,that people can view from all three dimensions, talk to a technical specialist, and get all questions answered.It could be used for education, shopping around, and collaborating with others.
Anyways, I haven't heard the results, but I had fun anyways.
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Last week, in my posting on Toshiba's latest 1.8" drive, Robert Pearson asks:
You may not be the right person to ask but I am asking everyone so "How do you see hybrid disk drives?"
(For the record, I am not immediately related to Robert. At onepoint, "Pearson" was the 12th most common surname in the USA, but now doesn't even make the Top 100.)
Robert, I would like to encourage you and everyone else to ask questions, don't worry if I am the wrong person to ask, asprobably I know the right person within IBM. Some people have called me the "Kevin Bacon" of Storage,as I am often less than six degrees away from the right person, having worked in IBM Storage for over 20 years.
For those not familiar with hybrid drives, there is a good write-up in Wikipedia.
Unfortunately, most of the people I would consult on this question, such as those from Market Intelligence or Research, are on vacation for the holidays, so, Robert, I will have to rely on my trusted 78-card Tarot deck and answer you with a five-card throw.
technorati tags: Robert Pearson, Kevin Bacon, IBM, storage, Tarot, card, deck, Hermit, Four-of-Cups, Coupling Facility, Chariot, SAN Volume Controller, SVC, SPC-1, SPC-2, benchmarks, Texas Memory Systems, Eight-of-Pentacles, World, Hybrid, SATA[Read More]
I got an interesting email from a new blogger asking me for advice on how frequently to post entries.I am probably not the right person to ask, as I blog whenever a thought comes to mind that I think otherswould enjoy reading, and sometimes that means several times a day, and other times only a few per month.I actually have a day job, busy doing other things, and blogging is just now part of my general set of activities.My focus is quality not quantity.
With that in mind, I was delightfully surprised that this blog was ranked among theTop 10 Storage Blogs by Network World, which explains my recent spike in traffic.
I shared the news with my 72-year-old father, and he exclaimed "There are actually 10 or more blogsto cover the IT storage industry?" He couldn't understand why the world would read more than two or three. I personally track thirty-five of them, and I suspect there are hundredsothers out there. Of these, some blog quite regularly, while others do not, so I am in good company. Deni Connor, the author who selected these top 10, gave a nice general complement tothe entire list of blogs:
The blogs written by storage company executives can be surprisingly vendor-agnostic, though the analysts and consultants still tend to pull fewer punches.
And this was my goal as well, to enlighten and entertain, in a fair and balanced manner, that adds value to the blogosphere, rather than just repeat the IBM press releases of each day. If you are just looking for "announcements" there is an RSS feed for IBM System Storage you cansubscribe to.
Not surprisingly, two of the blog entries that Deni mentions are the ones I get the most comments on:
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On his "Data Storage - Dullness becomes Mainstream" blog, Chris Evans is
amazed athow low they can go!.He compares the latest 100GB Toshiba 1.8" drive designed for portable music players, to the size andweight of older technology, like the IBM 3380 Direct Access Storage Device (DASD).
Chris couldn't find the dimensions of the 3380, so I thought I would provide the missing detail.The IBM 3380 History Archivesprovides a nice summary:
At least take a backup first.Read More]
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On SearchStorage.com, my buddy Tony Asaro recaps the latest Storage Acquisition Frenzy.
It has always been the case in fast pace technology areas that you can't tell the players without a program card, andthis is especially true for storage.
When analyzing each acquistion move, you need to think of what is driving it. What are the motives?Having been in the storage business 20 years now, and seen my share of acquisitions, both from within IBM,as well as competition, I have come up with the following list of motives.
I hope that provides some insight.[Read More]
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Chris Anderson, of Wired magazine, wrote a great article called The Long Tail.
This article became a book by the same name published earlier this year, and I just discovered it on a recent visit to Second Life. A lot of IBMers are now alsoSecond Lifers, and I suspect it is just a matter of time before we are conductingour customer briefings there, and getting our year-end bonuses paid directly in Linden bucks.(Those of you not familiar with Second Life can watch this 3-minute video fromthe folks at Text100)
Anyways, the Long Tail describes the new economy of entertainment thanks to digitalstorage. Here are some of the key insights.
This has incredible implications for the storage industry. For one, content providers are going to dig deep into their archives to digitize and deliver "long tail" offerings. If they don't have a deep archive, many will start to build one. Second, the need to search through that large volume of content will become more critical. Classifying and indexing with the appropriate tags and metadata will be an important task.
technorati tags: Chris Anderson, Wired, magazine, IBM, Secondlife, Linden bucks, Text100, Long Tail, Robbie+Vann-Adibe, eCast, NetFlix, iTunes, Amazon, Tap Room, Barnes Noble, deep, archive, metadata, tags
Last week, David Pogue (New York Times) wrote a blog entry on The Dilemma Over Future Storage Formats.
Of course, he is focused on the home user, and not the bigger mess found in the corporate world, where Federal Rules like the one past last week that begin to mandate that all U.S. companies archive every e-mail and instant message (IM) generated by their employees.
However, the article does bring up issues that effect the corporate world as well. Its not the "format" as much as the medium/player interface. A friend of mine just bought a vintage 8-track-tape player, but has only one 8-track tape to try it out with. He is now looking on eBay for other 8-track tapes.
The idea of keeping old drives around to read back data is not new. A company called eMag Solutions has all kinds of older tape drives to help companiesretrieve data on their older 3420 and 3480 tape cartridges.
The problem is not just accessing the data on the media, but rendering the "ones" and "zeros" into meaningful information. For example, suppose I saved a copy of my Quicken Tax file every year, and copied them onto a singleDVD for long term storage. The problem is that to access 2002 tax data, I have to run that version of the Quicken 2002 program, and hopefully that version will run on my current computer equipment and operating system.
A client I visited earlier this year had to retrieve 4-year-old Oracle data for litigation reasons. However, to make sense of the data, they had to build a server with a down-level version of AIX and down-level version of Oracle to match the level supported by their homegrown application.
One solution might be to find a new format that is appl Luckily, for the corporate world, IBM has a lot of experience in this area, is the leader in Content Management, offers the world's fastest archive/compliance storage, the DR550, clocked at three times faster than the EMC Centera, WORM tape on LTO Generation 3 and 3592 tape cartridges, and software designed to render older formats into readable form. For the home user, IBM's recent "Innovation Jam" identified this as one of the top 10 ideas, the idea of "Digital Me", storing not just old tax documents, but photos, music, home videos, and so on. My aunt Nancy passed away, leaving me a box of old VHS tapes, which I will watch this month as I sort through all my paper receipts getting ready to file for 2006 taxes.
Luckily, for the corporate world, IBM has a lot of experience in this area, is the leader in Content Management, offers the world's fastest archive/compliance storage, the DR550, clocked at three times faster than the EMC Centera, WORM tape on LTO Generation 3 and 3592 tape cartridges, and software designed to render older formats into readable form.
For the home user, IBM's recent "Innovation Jam" identified this as one of the top 10 ideas, the idea of "Digital Me", storing not just old tax documents, but photos, music, home videos, and so on. My aunt Nancy passed away, leaving me a box of old VHS tapes, which I will watch this month as I sort through all my paper receipts getting ready to file for 2006 taxes.Read More]
Ken Gibson has written a four-part series about where the storage industry is going, on his Storage Thoughts blog. You can find the four parts here (Part 1,Part 2,Part 3,Part 4).
His analysis of the storage industry is based on the concepts in Clayton Christensen's latest book Seeing What's Next, his latest work on the heels of his last two successes "The Innovator's Dilemma" and "The Innovator's Solution". I've only read the first book, "The Innovator's Dilemma" but need to check out these other two.
Ken explores the efforts of the incumbent players, and I agree IBM is farthest along, but not only for our "Storage Tank" architecture. For those not aware of Storage Tank, it was the code-name of a project from IBM's Almaden Research Center, productized as IBM System Storage SAN File System (SFS). Earlier this year the advanced policy-based data placement, movement and expiration features of SFS were copied over to IBM's General Parallel File System (GPFS) which has wide adoption among the High-Performance Technical Computing (HPTC) community. As I've said before, switching from one file system to another is hard, so it makes sense for HPTC clients who already use GPFS to make use of these new features by staying with GPFS, rather than trying to get them to move to SFS.
I also like Ken's analysis of "overshot" and "undershot" clients. Overshot clients are those that find what the marketplace delivers already "good enough" for their needs, and are price sensitive against paying for features they don't think they need. The undershot clients are those that the current marketplace set of offerings are not yet good enough, and are willing to pay a premium to the vendor or supplier that can get them closer to what they are looking for.
Changes are underfoot, and it is an exciting time to be involved in the storage industry.[Read More]
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Our industry is full of acronyms, and sometimes spelling out what words an acronym stands for is not enough to explain it fully.
It reminds me of an old story within IBM. A customer engineer (or "CE" for short) was repairing an air-cooled server, and found the failing part being a "FAN". Not knowing what this stood for, he looked up the acronym in the offical "IBM list of acronyms" and found that it stood for "Forced Air Network". Apparently, so many people did not realize that a FAN was just a "fan" that they needed to add an entry to remind people what this little motorized propeller was for.
This brings me to Tony Asaro's Fun with FAN blog entry which mentions yet another definition for FAN, that of "File Area Network". The concept is not new, but some developments this year help make it more a reality.
To join the rest of the world, new types of data set were created for the z/OS operating system, known as HFS and zFS. These held file systems in the sense we know them today, comparable in hierarchical organization of files on Windows, Linux and UNIX platforms. These could be linked and mounted together in larger hierarchical structures across the sysplex.
The concept of files and file systems is a fairly new concept. Prior to this, applications read and wrote directly in terms of blocks, typically fixed length multiples of 512 bytes. For a while, database management systems offered a choice, direct block access or file level access. The former may have offered slightly better performance, but the latter was easier to administer. Without file system, specialized tools were often required to diagnose and fix problems on block-oriented "raw logical" volumes.
This launched a "my file system is better than yours" war which continues today. The official standard is POSIX, but every file system tries to give some proprietary advantage by offering unique features. Sun's file system offers support for "sparse" files, which is ideal for certain mathematical processing of tables. Microsoft's NTFS offers biult-in compression, designed for the laptop user. IBM's JFS2 and Linux's EXT3 file systems support journaling, which tracks updates to file system structures in a separate journal to minimize data corruption in the event of a power outage, and thus speed up the re-boot process. Anyone who has ever waited for a "Scan Disk" or "fsck" process to finish knows what I'm talking about. Of course, if an application deviates from POSIX standards, and exploits some unique feature of a file system, it then limits its portability and market appeal.
The two competing NAS file systems are also different. Common Internet File System (CIFS) was developed initially by IBM and Microsoft to provide interoperability between DOS, Windows and OS/2. Meanwhile, Network File System (NFS) was the darling of nearly every UNIX and Linux distribution, and even has clients on operating platforms as diverse as MacOS, i5/OS, and z/OS. Today, nearly every platform supports one or both of these standards.
Bottom line, file systems are here to stay. Any slight advantages to use raw logical volumes for databases and applications are losing out to the robust set of file system utilities that can be used across a broad set of platforms and applications.Read More]