I got some interesting queries about IBM's Scale-Out File Services [SoFS
] that I mentioned in my post yesterday [Area rugs versus Wall-to-Wall carpeting
]. I thought I would provide some additional details of the product.
SoFS combines three key features: a global namespace, a clustered file system, and Information LifecycleManagement (ILM). Let's tackle each one.
- Global Name Space
A long time ago, IBM acquired a company called Transarc that developed Andrew File System (AFS) and DistributedFile System (DFS). These both provided global namespace capability, meaning that all of your files could beaccessible from a single URL file tree. Imagine if you have data centers in Tucson, Austin, Raleigh and Chicago.Normally, to access files from each city, you would have to mount a unique IP address for that location, and thento get to files in a different city, you'd have to mount a second, and so on. But with a global namespace, you could mount a single drive letter Z: and access files simply by using Z:/Tucson/abc or Z:/Austin/xyz. IBM uses its DFS to make this happen.
Just because you have access to a global namespace doesn't give you read/write authority to every file. IBM SoFS has full NTFS Access Control List (ACL) support, so that only those who can read or write data can access the files. A "hide unreadable" feature provideswhat I like to call "parental controls": you don't even get to see on your directly list any file or subdirectory that you don't have access to. For example, if there is a directory with 50 projects, but you only have authority tothree projects, then you only see the three subdirectories related to those projects, and nothing else.
There are other ways to get a global namespace. IBM also offers the IBM System Storage N series Virtual FileManager, Brocade offers Storage/X, and F5 acquired Acopia. These all work by putting a box in front of a set ofindependent NAS storage units, and giving you a single mount point to represent all of the file systems managedbehind the scenes. This however can sometimes be a bottleneck for performance.
- Clustered File System
Often, when you have a lot of data in one place, you are also expected to deliver that data to lots of clientswith relatively good performance. Otherwise, end users revolt and get their own internal direct attach storage.To solve this, you need a clustered architecture that provides access in parallel to the data.
First, we start with a node that is optimized for CIFS and NFS access. We have clocked our node to run CIFS at577 MB/sec, and NFS at 880 MB/sec, through a 10GbE pipe between a single client and a single SoFS node. Comparethat to the 400 MB/sec you get today with 4Gbps FCP, or the 800 MB/sec you will get if you upgrade to 8 GbpsFCP, and quickly you recognize that this is comparable performance for demanding workloads.
Then, you combine multiple nodes together, and have them all be able to read/write any file in the file system, andfront-end that with a load-balancing Virtual IP address (VIPA) that spreads the requests around, and you've gotyourself a lean and mean machine for accessing data.
In 2005, IBM delivered[ASC Purple] with the world's fastest file system. 1536 nodeswere able to access billions of files in the 2 Petabyte of data. The record of 126 GB/sec access to a single filewas set, and has yet to be beaten by any other vendor since.This same file system is used in SoFS, as well as a variety of other IBM storage offerings.
The back-end storage can be SAS or FC-attached, from the DS3200 to our mighty DS8300 Turbo, as well as ourIBM System Storage DCS9550 and SAN Volume Controller (SVC), and a variety of tape libraries.
- Information Lifecycle Management
Lastly, we get to ILM. With SoFS, you can have different tiers of storage, high-speed SAS or FC disk, low-speedFATA and SATA disk, and even tape. Policy-based automation allows you to place any file onto any disk tier whencreated, and other policies can migrate or delete the data trigged by certain threshold, age, or other criteria.The advantage is that this is on a file by file basis, so Z:/Tucson/Project could have a bunch of files, some ofthem on my FC disk, some of them on my SATA, and some on tape. The file path doesn't change when they move, anddifferent files in the same directory can be on different tiers.
Data movement is bi-directional. If you know you will be using a set of files for an upcoming job, say perhapsquarter-end or year-end processing, you can pre-fetch those files from tape and move them to your fastest disk pool.
There is also integrated backup support. Typically, a large NAS environment is difficult to backup. Traditionalmethods take days to scan the directory tree looking for files in need of backup. A single SoFS node can scana billion files in 95 minutes, and 8 nodes in a cluster can scan a billion files in under 15 minutes.
Recovery is even more impressive. When you recover, SoFS brings back the entire directory structure first, withall the file names in place. This would make it appear that all the data is restored, but actually it is still on tape.When you access individual files, it will then drive the recovery of that file, so your applications and end usersbasically determine the priority of the recovery. Traditional methods would wait until every file was restoredbefore letting anyone access the system.
SoFS is part of IBM's [Blue Cloud] initiativethat was launched last November 2007. Of course, IBM isn't the only one competing in this space. HDS has partneredwith BlueArc, HP has acquired PolyServe, and Sun acquired CFS for their Lustre file system. Isilon and Exanet arestart-up companies with some offerings. EMC acquired Rainfinity,and have hinted at a Hulk/Maui project that they might deliver later this year or perhaps in 2009, but by thenmight be a dollar-short and a day-late.
But why wait? IBM SoFS is available today and is orders of magnitude more scalable!
technorati tags: IBM, SoFS, Acopia, VFM, Brocade, ILM, global namespace, clustered, file system, disk, tape, storage, system, CIFS, NFS, NAS, NTFS, ACL, DFS, AFS, Transarc, ASC Purple, DS3200, SAS, FC, FCP, DS8300, Turbo, DCS9550, SVC, FATA, SATA, nodes, backup, restore, recovery, Blue Cloud, cloud computing, PolyServe, HDS, BlueArc, HP, Sun, CFS, Lustre, Isilon, Exanet, EMC, Rainfinity, Hulk, Maui
Last week, I covered backup issues in [Deduplicationversus Best Practice for Backups
]. This week, I thought I would cover issues with email.
At IBM, our standard is to have a limit of 200MB per user mailbox. A few of us get exceptions and have up to500MB limit because of the work we do. By comparison, my personal Gmail account is now up to 6500MB. Whenthis limit is exceeded, you are unable to send out any mail until it is brought down below the limit, and a request to be "re-enabled for send" is approved, a situation we call "mail jail".
The biggest culprit are attachments. Only 10 percent of emails have attachments, but those that do take up 90percent of the total space! People attach a 15MB presentation or document, and copy the world ondistribution list. Everyone saves their notes with these attachments, and soon, the limits are blown. Not surprisingly, deduplication has been cited as a "killer app" to address email storage, exactly for this reason.If all the users have their mailboxes all stored on the same deduplication storage device, it might find theseduplicate blocks, and manage to reduce the space consumed.
A better practice would be to avoid this in the first place. Here are the techniques I use instead:
- Point to the document in a database
We are heavy users of Lotus Notes databases. These can be encrypted and controlled with Access Control Lists (ACL)that determine who can create or read documents in each database. Annually, all the database ACLs are validatedso that people can confirm that they continue to have a need-to-know for the documents in each database. Sendinga confidential document as a "document link" to a database entry takes only a few bytes, and all the recipientsthat are already on the ACL have access to that document.
- Point to the document on a web page
If the document is available on an internal or external website, just send the URL instead of attaching the file.Again, this takes only a few bytes. We have websites accessible only to all internal employees, websites thatcan be accessed only by a subset of employees with special permissions and credentials based on their job role, and websites that are accessible to our IBM Business Partners.
In my case, if I happen to have a blog posting that answers a question or helps illustrate an idea, I will sendthe "permalink" URL of that blog post in my email.
- Point to the document on shared NAS file system
Internally, IBM uses a "Global Storage Architecture" (GSA) based on IBM's Scale-Out File Services [SoFS] with everyone getting initially 10GB of disk space to store files, with the option to request more if needed. The system has policy-based support for placing and migrating older data to tape to reduce actual disk usage, and combines a clustered file system with a global name space.
My SoFS space is now up to 25GB, and I store a lot of presentationsand whitepapers that are useful to others. A URL with "ftp://" or "http://" is all you need to point to a filein this manner, and greatly reduces the need for attachments. I can map my space as "Drive X:" on my Windows system,or as a NFS mount point on my Linux system, which allows me to easily drag files back and forth.
Departments that don't need to offer "worldwide access" use NAS boxes instead, such as the IBM System Storage N series.
Pointing to files in a shared space, rather than as attachments in email, may take some getting used to. I've hada few recipients send me requests such as "can you send that as an attachment (not a URL)" because they plan toread it on the airplane or train, where they won't have online connectivity.
This all relates to new ways for employees to collaborate. Shawn from Anecdote writes in the post[Fostering a Collaboration Culture]:
"Have you invested in the latest and greatest in collaboration technology but still feel people are still not collaborating? How many Microsoft Sharepoint servers and IBM Quickplaces remain relatively untouched or only used by the organization's technorati? I think it's a big problem because this narrow view of collaboration starts to get the concept a bad name: "yeah, we did collaboration but no one used it." And then there the issue of the vast amount of money wasted and opportunities lost. We can't afford to loose faith in collaboration because the external environment is moving in a direction that mandates we collaborate. The problems we face now and into the future will only increase in complexity and it will require teams of people within and across organizations to solve them."
Well, sending pointers instead of attachments works for me, and has kept me out of "mail jail" for quite some timenow.
technorati tags: IBM, deduplication, email, mailbox, Gmail, attachment, Lotus, Notes, database, URL, Permalink, GSA, NAS, SoFS, disk, Anecdote
As a consultant, I am often asked to help design the architecture for the information infrastructure. A usefulanalogy to gather requirements and preferences is the difference between area rugs
and wall-to-wall carpeting
. Arearugs are not secured to the floor and cover only a portion of the floor area. Carpets are generally tacked or cemented to the floor, often with an underlay of cushion padding, stretched across the entire floor surface, out to all four walls of each room.
Each has its pros and cons, and often is a matter of preference. Some people like area rugs because they can choosea different style for each room, match the decor and color scheme of furniture, and use these to define each livingspace. Ever since paleolithic man put animal skins on the floor of their cave, people recognize that cold, hard andugly floors could be covered up with something soft and more attractive.Others prefer wall-to-wall carpeting because they want to walk around the house barefoot, have their young children crawl on their hands and knees, and give the entire house a unified look and feel. This is often an inexpensive option when compared against the cost of individual rugs.
The same is true for an information infrastructure. For some, they prefer the "area rug" approach: this style ofstorage for their email, this other type of storage for their databases, and perhaps a third for their unstructuredfile systems. When customers ask what storage would I recommend for their SAP application, or their Microsoft Exchangeemail environment, or their Business Intelligence (BI) software, I recognize they are taking this "area rug" approach.
Like area rugs, having different storage can focus on specific attributes of the workload characteristics. It alsoinsulates against company-wide changes, the dreaded "rip-and-replace" of replacing all of your storage with somethingfrom a different vendor. With "area rug" storage, you can support a dual-vendor or multi-vendor strategy, and upgrade or replace each on its own schedule.
Thanks to open standards and industry-standard benchmarks, changing out one storage solution for another is assimple as rolling up an area rug, and putting another one in its place that is similar in size dimensions.
|Others may prefer "wall-to-wall carpeting" approach: one disk system type, one tape library type,one network type, that provides unified management and minimizes the needs for unique skills. Generally, the choice of NAS, SAN or iSCSI infrastrucutre is done company-wide, and might strongly influence the set of products that will support that decision. For example, those with a mix of mainframe and distributed servers looking for SAN-attached storage may look at an [IBM System Storage DS8000] and [TS3500 tape library] that can provide support for FICON and FCP.|
Those looking at NAS or iSCSI might consider the IBM System Storage N series products, "unified storage" supporting iSCSI, FCP and NAS protocols. If you want the "wall-to-wall" to stretch across all the sites in your globally integrated enterprise, IBM's scalable NAS product, Scale-Out File Services[SoFS], provides a global name spacein combination with a clustered file system that provides incredible scalability and performance based on field-proven technology used by the majority of the [Top 100 supercomputer] deployments.
IBM can help you design an information infrastructure that fits either approach.
technorati tags: IBM, DS8000, TS3500, NAS, SAN, iSCSI, FCP, FICON, mainframe, distributed, SoFS, supercomputer
No, this is not an announcement about myself moving to Nepal.
My friends over at OLE Nepal are [looking for a Super SysAdmin]willing to live in Nepal for five months and help out with their project to help the students in the localschools there. I think this might be a great opportunity for someone to help changethe world. Those of you who have read my past blog posts about the One Laptop per Child [OLPC], such as [Understanding the LAMP platform] and [Supporting OLPC Schools with LAMP stacks] may understand the type of work involved.
- You dream in Bash
- IPv4, IPv6, Wireless Mesh networking? No problem! You know linux networking inside and out
- Extensive knowledge of BIND, DHCPD, Squid, Apache, security, etc.
- Experience working with [Moodle] would be most excellent (it is basically a PHP web application that maintains MySQL databases for lesson plans, homework assignments and other school related information)
- Adept with Python scripting or could learn it quickly. OLPC has standardized on Python for scripting (although knowledge in Perl and PHP won't hurt either)
- You look to implement a practical solution that less skilled sysadmins can easily maintain over a cooler but more complicated solution.
- You play well with others. You don’t alienate collaborators with rude e-mails that assert your technical superiority (even though you are)
- Your primary concern is meeting the educational needs of kids and teachers. Your rate technical awesomeness a distant second to meeting those critical needs.
I've been working with Dev, Bryan and Sulochan for the past three months (remotely here from Tucson, AZ)but we've come to a point where we need on-site expertise. I will continue to provide remote support.
Given the number of readers who have contacted me over the past year looking for an IT job (or a different job because they are not happy where they are), this could be an amazing experience.
technorati tags: OLE Nepal, OLPC, Bash, Linux, IPv6, Mesh, networking, Squid, Apache, security, Moodle, LAMP, PHP, Perl, Python
IDC, an independent industry analyst firm, put out their 4Q07"Worldwide Disk Storage Systems Quarterly Tracker" report. Here is an excerpts from their [press release
"Worldwide external disk storage systems factory revenues posted 9.8 percent year-over-year growth in the fourth quarter of 2007 (4Q07) and totaling $5.3 billion (USD), according to the IDC Worldwide Disk Storage Systems Quarterly Tracker. For the quarter, the total disk storage systems market grew to $7.5 billion (USD), up 7.6 percent from the prior year's fourth quarter. Total disk storage systems capacity shipped reach 1,645 petabytes, growing 56.3 percent."
For those wondering how an industry could grow 56.3 percent in capacity, but only 7.6 percent in revenue, it isbecause the average dollar-per-GB dropped in 2007 from $6.63 down to $4.56 (USD), representing a 31 percent decline.In the past, disk prices dropped 40 to 60 percent each year, so making single digit growth was the best major vendorscould hope for. However, lately this has slowed down to 25 to 35 percent decline, but the client demand for capacity continues at the 60 percent pace, which means that vendors could achieve double digit revenue growth soon.
Once again, IBM was ranked number 1 in total disk storage. No surprise there. Here are the details:
"Total Disk Storage Systems Market
In the total worldwide disk storage systems market, IBM lead the market with 22.9 percent followed by HP with 18.1 percent revenue share. EMC maintained the third position with 16.0 percent revenue share.
For the full year, the total disk storage systems market posted 6.6 percent growth to $26.3 billion (USD). In the total worldwide disk storage systems market, IBM and HP lead the market in statistical tie with 20.1 percent and 19.4 percent revenue share, respectively. EMC maintained the third position with 15.2 revenue revenue share."
But why focus just on disk? IDC also released their"Worldwide Combined Disk and Tape Storage 3Q07 Market Share Update", and IBM was number one for that as well,taking in 21.9 percent share. Here's a quote of IBM VP Barry Rudolph in[CNN Money]:
"IBM's continued leadership in the storage hardware market reaffirms our strategy to provide the most comprehensive tiered portfolio of storage offerings, ranging from software and services to disk and tape storage solutions," said Barry Rudolph, Vice President, Storage Stack Solutions, IBM. "IBM is the clear choice for providing information infrastructure solutions that offer the most cost-efficient, streamlined approach to help our customers increase overall productivity and maximize performance."
It is looking like 2008 is going to be a good year for IBM!
technorati tags: IBM, IDC, 4Q07, 3Q07, marketshare, market share, EMC, HDS, HP, Sun, NetApp, Dell, disk, tape, systems