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Tony Pearson is a Master Inventor, Senior IT Architect and Event Content Manager for [IBM Systems for IBM Systems Technical University] events. With over 30 years with IBM Systems, Tony is frequent traveler, speaking to clients at events throughout the world.
Lloyd Dean is an IBM Senior Certified Executive IT Architect in Infrastructure Architecture. Lloyd has held numerous senior technical roles at IBM during his 19 plus years at IBM. Lloyd most recently has been leading efforts across the Communication/CSI Market as a senior Storage Solution Architect/CTS covering the Kansas City territory. In prior years Lloyd supported the industry accounts as a Storage Solution architect and prior to that as a Storage Software Solutions specialist during his time in the ATS organization.
Lloyd currently supports North America storage sales teams in his Storage Software Solution Architecture SME role in the Washington Systems Center team. His current focus is with IBM Cloud Private and he will be delivering and supporting sessions at Think2019, and Storage Technical University on the Value of IBM storage in this high value IBM solution a part of the IBM Cloud strategy. Lloyd maintains a Subject Matter Expert status across the IBM Spectrum Storage Software solutions. You can follow Lloyd on Twitter @ldean0558 and LinkedIn Lloyd Dean.
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Back in June, I mentioned this blog was [Moving to MyDeveloperWorks] which is based on IBM Lotus Connections.
Finally, the move is complete for all bloggers. If you are having problems with the redirects, you might need to unsubscribe and re-subscribe in your RSS feed reader. Here are the new links for several IBM bloggers that have moved over:
Continuing my week in Chicago, for the IBM Storage Symposium 2008, we had sessions that focused on individual products. IBM System Storage SAN Volume Controller (SVC) was a popular topic.
SVC - Everything you wanted to know, but were afraid to ask!
Bill Wiegand, IBM ATS, who has been working with SAN Volume Controller since it was first introduced in 2003. answered some frequently asked questions about IBM System Storage SAN Volume Controller.
Do you have to upgrade all of your HBAs, switches and disk arrays to the recommended firmware levels before upgrading SVC? No. These are recommended levels, but not required. If you do plan to update firmware levels, focus on the host end first, switches next, and disk arrays last.
How do we request special support for stuff not yet listed on the Interop Matrix?
Submit an RPQ/SCORE, same as for any other IBM hardware.
How do we sign up for SVC hints and tips? Go to the IBM
[SVC Support Site] and select the "My Notifications" under the "Stay Informed" box on the right panel.
When we call IBM for SVC support, do we select "Hardware" or "Software"?
While the SVC is a piece of hardware, there are very few mechanical parts involved. Unless there are sparks,
smoke, or front bezel buttons dangling from springs, select "Software". Most of the questions are
related to the software components of SVC.
When we have SVC virtualizing non-IBM disk arrays, who should we call first?
IBM has world-renown service, with some of IT's smartest people working the queues. All of the major storage vendors play nice
as part of the [TSAnet Agreement when a mutual customer is impacted.
When in doubt, call IBM first, and if necessary, IBM will contact other vendors on your behalf to resolve.
What is the difference between livedump and a Full System Dump?
Most problems can be resolved with a livedump. While not complete information, it is generally enough,
and is completely non-disruptive. Other times, the full state of the machine is required, so a Full System Dump
is requested. This involves rebooting one of the two nodes, so virtual disks may temporarily run slower on that
What does "svc_snap -c" do?The "svc_snap" command on the CLI generates a snap file, which includes the cluster error log and trace files from all nodes. The "-c" parameter includes the configuration and virtual-to-physical mapping that can be useful for
disaster recovery and problem determination.
I just sent IBM a check to upgrade my TB-based license on my SVC, how long should I wait for IBM to send me a software license key?
IBM trusts its clients. No software license key will be sent. Once the check clears, you are good to go.
During migration from old disk arrays to new disk arrays, I will temporarily have 79TB more disk under SVC management, do I need to get a temporary TB-based license upgrade during the brief migration period?
Nope. Again, we trust you. However, if you are concerned about this at all, contact IBM and they will print out
a nice "Conformance Letter" in case you need to show your boss.
How should I maintain my Windows-based SVC Master Console or SSPC server?
Treat this like any other Windows-based server in your shop, install Microsoft-recommended Windows updates,
run Anti-virus scans, and so on.
Where can I find useful "How To" information on SVC?
Specify "SAN Volume Controller" in the search field of the
[IBM Redbooks vast library of helpful books.
I just added more managed disks to my managed disk group (MDG), can I get help writing a script to redistribute the extents to improve wide-striping performance?
Yes, IBM has scripting tools available for download on
[AlphaWorks]. For example, svctools will take
the output of the "lsinfo" command, and generate the appropriate SVC CLI to re-migrate the disks around to optimize
performance. Of course, if you prefer, you can use IBM Tivoli Storage Productivity Center instead for a more
Any rules of thumb for sizing SVC deployments?
IBM's Disk Magic tool includes support for SVC deployments. Plan for 250 IOPS/TB for light workloads,
500 IOPS/TB for average workloads, and 750 IOPS/TB for heavy workloads.
Can I migrate virtual disks from one manage disk group (MDG) to another of different extent size?
Yes, the new Vdisk Mirroring capability can be used to do this. Create the mirror for your Vdisk between the
two MDGs, wait for the copy to complete, and then split the mirror.
Can I add or replace SVC nodes non-disruptively? Absolutely, see the Technotes
[SVC Node Replacement page.
Can I really order an SVC EE in Flamingo Pink? Yes. While my blog post that started all
this [Pink It and Shrink It] was initially just some Photoshop humor, the IBM product manager for SVC accepted this color choice as an RPQ option.
The default color remains Raven Black.
Continuing my week in Chicago, for the IBM Storage Symposium 2008, I attended two presentations on XIV.
XIV Storage - Best Practices
Izhar Sharon, IBM Technical Sales Specialist for XIV, presented best practices using XIV in various environments.He started out explaining the innovative XIV architecture: a SATA-based disk system from IBM can outperformFC-based disk systems from other vendors using massive parallelism. He used a sports analogy:
"The men's world record for running 800 meters was set in 1997 by Wilson Kipketer of Denmark in a time of 1:41.11.
However, if you have eight men running, 100 meters each, they will all cross the finish line in about 10 seconds."
Since XIV is already self-tuning, what kind of best practices are left to present? Izhar presented best practicesfor software, hosts, switches and storage virtualization products that attach to the XIV. Here's some quickpoints:
Use as many paths as possible.
IBM does not require you to purchase and install multipathing software as other competitors might. Instead, theXIV relies on multipathing capabilities inherent to each operating system.For multipathing preference, choose Round-Robin, which is now available onAIX and VMware vSphere 4.0, for example. Otherwise, fixed-path is preferred over most-recently-used (MRU).
Encourage parallel I/O requests.
XIV architecture does not subscribe to the outdated notion of a "global cache". Instead, the cache is distributed across the modules, to reduce performance bottlenecks. Each HBA on the XIV can handle about 1400requests. If you have fewer than 1400 hosts attached to the XIV, you can further increase parallel I/O requests by specifying a large queue depth in the host bus adapter (HBA).An HBA queue depth of 64 is a good start. Additional settings mightbe required in the BIOS, operating system or application for multiple threads and processes.
For sequential workloads, select host stripe size less than 1MB. For random, select host stripe size larger than 1MB. Set rr_min_io between ten(10) and the queue depth(typically 64), setting it to half of the queue depth is a good starting point.
If you have long-running batch jobs, consider breaking them up into smaller steps and run in parallel.
Define fewer, larger LUNs
Generally, you no longer need to define many small LUNs, a practice that was often required on traditionaldisk systems. This means that you can now define just 1 or 2 LUNs per application, and greatly simplifymanagement. If your application must have multiple LUNs in order to do multiple threads or concurrent I/O requests, then, by all means, define multiple LUNs.
Modern Data Base Management Systems (DBMS) like DB2 and Oracle already parallelize their I/O requests, sothere is no need for host-based striping across many logical volumes. XIV already stripes the data for you.If you use Oracle Automated Storage Management (ASM), use 8MB to 16MB extent sizes for optimal performance.
For those virtualizing XIV with SAN Volume Controller (SVC), define manage disks as 1632GB LUNs, in multiple of six LUNs per managed disk group (MDG), to balance across the six interface modules. Define SVC extent size to 1GB.
XIV is ideal for VMware. Create big LUNs for your VMFS that you can access via FCP or iSCSI.
Organize data to simplify Snapshots.
You no longer need to separate logs from databases for performance reasons. However, for some backup productslike IBM Tivoli Storage Manager (TSM) for Advanced Copy Services (ACS), you might want to keep them separatefor snapshot reasons. Gernally, putting all data for an application on one big LUNgreatly simplifies administration and snapshot processing, without losing performance.If you define multiple LUNs for an application, simply put them into the same "consistencygroup" so that they are all snapshot together.
OS boot image disks can be snapshot before applying any patches, updates or application software, so that ifthere are any problems, you can reboot to the previous image.
Employ sizing tools to plan for capacity and performance.
The SAP Quicksizer tool can be used for new SAP deployments, employing either the user-based orthroughput-based sizing model approach. The result is in mythical unit called "SAPS", which represents0.4 IOPS for ERP/OLTP workloads, and 0.6 IOPS for BI/BW and OLAP workloads.
If you already have SAP or other applications running, use actual I/O measurements. IBM Business Partners and field technical sales specialists have an updated version of Disk Magic that can help size XIV configurations fromPERFMON and iostat figures.
Lee La Frese, IBM STSM for Enteprise Storage Performance Engineering, presented internal lab test results forthe XIV under various workloads, based on the latest hardware/software levels [announced two weeks ago]. Three workloadswere tested:
Web 2.0 (80/20/40) - 80 percent READ, 20 percent WRITE, 40 percent cache hits for READ.YouTube, FlickR, and the growing list at [GoWeb20] are applications with heavy read activity, but because of[long-tail effects], may not be as cache friendly.
Social Networking (50/50/50) - 50 percent READ, 50 percent WRITE, 50 percent cache hits for READ.Lotus Connections, Microsoft Sharepoint, and many other [social networking] usage are more write intensive.
Database (70/30/50) - 70 percent READ, 30 percent WRITE, 50 percent cache hits for READ.The traditional workload characteristics for most business applications, especially databases like DB2 andOracle on Linux, UNIX and Windows servers.
The results were quite impressive. There was more than enough performance for tier 2 application workloads,and most tier 1 applications. The performance was nearly linear from the smallest 6-module to the largest 15-module configuration. Some key points:
A full 15-module XIV overwhelms a single SVC 8F4 node-pair. For a full XIV, consider 4 to 8 nodes 8F4 models, or 2 to 4 nodes of an 8G4. For read-intensive cache-friendly workloads, an SVC in front of XIV was able to deliver over 300,000 IOPS.
A single node TS7650G ProtecTIER can handle 6 to 9 XIV modules. Two nodes of TS7650G were needed to drivea full 15-module XIV. A single node TS7650 in front of XIV was able to ingest 680 MB/sec on the seventh day with17 percent per-day change rate test workload using 64 virtual drives. Reading the data back got over 950 MB/sec.
For SAP environments where response time 20-30 msec are acceptable, the 15-module XIV delivered over 60,000 IOPS. Reducing this down to 25,000-30,000 cut the msec response time to a faster 10-15 msec.
These were all done as internal lab tests. Your mileage may vary.
Not surprisingly, XIV was quite the popular topic here this week at the Storage Symposium. There were many moresessions, but these were the only two that I attended.
Continuing my week in Chicago, at the IBM System x and BladeCenter Technical Conference, I attended an
awesome session that summarized IBM's Linux directions. Pat Byers presented the global forces that are
forcing customers to re-evaluate the TCO of their operating system choices, the need for rapid integration
in an ever-changing business climate, government stimulus packages, and technology that has enabled much
better solutions than we had during the last economic turn-down in 2001-2003.
IBM has been committed to Linux for over 10 years now. I was part of the initial IBM team in the 1990s to work on Linux for the mainframe. In various roles, I helped get Linux attachment tested for disk and tape systems, and helped get Linux selected as an operating system platform of choice for our storage management software.
Today, Linux-based server generate $7 Billion US dollars in revenues. For UNIX customers, Linux provides greater flexibility for hardware platform. For Windows customers, Linux provides better security and reliability.
Initially, Linux was used for simple infrastructure applications, edge-of-the-network and Web-based workloads.
This evolved to Application and Data serving, Enterprise applications like ERP, CRM and SCM. Today,
Linux is well positioned to help IBM make our world a smarter planet, able to handle business-critical applications. It is the only operating system to scale to the full capability of the biggest IBM System x3950M2 server.
Pat gave an examples of IBM's work with Linux helping clients.
City of Stockholm
The city of Stockholm, Sweden introduced congestion pricing to reduce traffic.
IBM helped them deploy systems to collect tariffs from 300,000 vehicles a day, with real-time scanning and recognition of vehicle license plates, Web-accessible payment processing, and analytics for metrics and reporting. This configuration was able to
[reduce traffic by 25 percent in the first month].
IBM helped [ConAgra Foods] switch their SAP environment from a monolithic Solaris on SPARC deployment, to a more distributed one using Novell SUSE Linux on x86. The result? Six times faster performance at 75 percent lower total cost of ownership!
IBM's strategy has been to focus on working with two of the major Linux distributors: Red Hat and Novell. It also works with [Asianux] which is like the UnitedLinux for Asia, internationalized for Japan, Korea, and China. It handles special requests for other distributions, from CentOS to Ubuntu, as needed on a case by case basis.
IBM's Linux Technology Center of 600 employees help to enable IBM products for Linux, make Linux a better operating system, expand Linux's reach, and help drive collaboration and innovation. In fact, IBM is the #3 corporate contributor to the open source Linux kernel, behind Red Hat (#1) and Novell (#2). For most IBM products, IBM tests with Linux as rigorously as it does Microsoft Windows. IBM offers complete RTS/ServicePac and SupportLine service and support contracts for Red Hat and Novell Linux.
At the IBM Solutions Center this week, several booths used Linux bootable USB sticks to run their software.
[Novell SUSE Studio] was developed to help
customize Linux to the specific needs for independent vendors.
Both Red Hat and Novell offer distributions in four categories:
Standard - for small entry-level servers, with support for a few virtual guests
Advanced Platform - for bigger servers, and support for many or unlimited number of virtual guests
High Performance Computing - HPC and Analytics for large grid deployments
Real Time - for real time processing, such as with
[IBM WebSphere Real Time], where
sub-second response time is critical.
A key difference between Red Hat and Novell appears to be on their strategy towards server virtualization.
Red Hat wants to position itself as the hypervisor of choice, for both servers and desk top virtualization, announcing Kernel-based Virtual Machine
[KVM] on their Red Hat Enterprise Linux (RHEL) 5.4 release, and their new upcoming
RHEV-V, a tight 128MB hypervisor to compete against VMware ESXi. Meanwhile, Novell is focusing SUSE to be
the perfect virtual guest OS, being hypervisor-aware an dhaving consistent terms and licensing when run under any hypervisor, including VMware, Hyper-V, Citrix Xen, KVM or others.
IBM has tons of solutions that are based on Linux, including the IBM Information Server blade, the InfoSphere Balanced Warehouse, SAN Volume Controller (SVC), TS7650 ProtecTIER data deduplication virtual tape library, Grid Medical Archive Solution (GMAS), Scale-out File Services (SoFS), Lotus Foundations, and the IBM Smart Cube.
If you are interested in trying out Linux, IBM offers evaluation copies at no charge for 30 to 90 days. For
more on how to deploy Linux successfully on IBM servers, see the
[IBM Linux Blueprints] landing page.
Continuing my week in Chicago, for the IBM Storage Symposium 2008, I attended several sessions intended to answer the questions of the audience.
In an effort to be cute, the System x team have a "Meet the xPerts" session at their System x and BladeCenter Technical Conference, so the storage side decided to do the same. Traditionally, these have been called "Birds of a Feature", "Q&A Panel", or "Free-for-All". They allow anyone to throw out a question, and have the experts in the room, either
IBM, Business Partner or another client, answer the question from their experience.
Meet the Experts - Storage for z/OS environments
Here were some of the questions answered:
I've seen terms like "z/OS", "zSeries" and "System z" used interchangeably, can you help clarify what this particular session is about?
IBM's current mainframe servers are all named "System z", such as our System z9 or System z10. These replace the older zSeries models of hardware. z/OS is one of the six operating systems that run on this hardware platform. The other five are z/VM, z/VSE, z/TPF, Linux and OpenSolaris. The focus of this session will be storage attached and used for z/OS specifically, including discussions of Omegamon and DFSMS software products.
What can we do to reduce our MIPS-based software licensing costs from our third party vendors?
Consider using IBM System z Integrated Information Processor
What about 8 Gbps FICON?
IBM has already announced
[FICON Express8] host bus adapter (HBA) cards, that will auto-negotiate to 4Gbps and 2Gbps speeds. If you don't need full 8Gbps speed now, you can
still get the Express8 cards, but put 4/2/1 Gbps SFP ports instead. Currently, LongWave (LW) is only supported to 4km at 8Gbps speed.
I want to use Global Mirror for my DS8100 to my remote DS8100, but also make test copies of my production data to
an older ESS 800 I have locally. Any suggestions? Yes, consider using FlashCopy to simplify this process.
I have Global Mirror (GM) running now successfully with DSCLI, and now want to deploy IBM Tivoli Storage Productivity Center for Replication. Is that possible? Yes, Productivity Center for Replication will detect existing GM relationships, and start managing them.
I have already deployed HyperPAV and zHPF, is there any value in getting Solid-State Drives as well?
HyperPAV and zHPF impact CONN time, but SSD impacts DISC time, so they are mutually complementary.
How should I size my FlashCopy SE pool? SE refers to "Space Efficient", which stores only the changes
between the source and destination copies of each LUN or CKD volume involved. General recommendation is to start with 20 percent and adjust accordingly.
How many RAID ranks should I configure per DS8000 extent pool? IBM recommends 4 to 8 ranks per pool.
Meet the Experts: Storage for Linux, UNIX and Windows distributed systems
This session was focused on storage systems attached to distributed servers, as well as products from Tivoli used to manage them. Here were some of the questions answered:
When we migrated from Tivoli Storage Manager v5 to v6, we lost our favorite "Operational Reporting" tool. How can we get TOR back? You now get the new Tivoli Common Reporting tool.
How can we identify appropriate port distribution for multiple SVC node pairs for load balancing?
IBM Tivoli Storage Productivity Center v4.1 has hot-spot analysis with recommendations for Vdisk migrations.
We tried TotalStorage Productivity Center way back when, but the frequent upgrades were killing us. How has it been lately? It has been much more stable since v3.3, and completely renamed to Tivoli Storage Productivity Center to avoid association with versions 1 and 2 of the predecessor product. The new "lightweight agents" feature of v4.1 resolve many of the problems you were experiencing.
We have over 1600 SVC virtual disks, how do we handle this in IBM Tivoli Storage Productivity Center? Use the Filter capability in combination with clever naming conventions for your virtual disks.
How can we be clever when we are limited to only 15 characters? Ok. We understand.
We are currently using an SSPC with Windows 2003 and 2GB memory, but we are only using the Productivity Center for Replication feature of it. Can we move the DB2 database over to a Windows 2008 server with 4GB of memory?
Consider using the IBM Tivoli Storage Productivity Center for Replication software instead of SSPC for special
circumstances like this.
We love the XIV GUI, how soon will all other IBM storage products have it also? As with every acquisition,
IBM evaluates if there are technologies from new products that can be carried back to existing products.
We are currently using 12 ports on our existing XIV, and love it so much we plan to buy a second frame, but are concerned about consuming another 12 ports on our SAN switch. Any suggestions? Yes, use only six ports per frame. Just because you have more ports, doesn't mean you are required to use them.
We have heard there are concerns from the legal community about using deduplication technology, any ideas how to address that?
Nobody here in the room is a lawyer, and you should consult legal counsel for any particular situation.
None of the IBM offerings intended for non-erasable, non-rewriteable (NENR) data retention records (DR550, WORM tape, N series SnapLock) support dedupe today, and none of IBM's deduplication offerings (TS7650,N series A-SIS,TSM) make any claims for fit-for-purpose for compliance regulatory storage. However, be assured that all of IBM's dedupe technology involves byte-for-byte comparisons so that you never lose any data due to false hash collisions. For all IBM compliance storage, what you write will be read back in the correct sequence of ones and zeros.