Tony Pearson is a Master Inventor and Senior IT Architect for the IBM Storage product line at the
IBM Systems Client Experience Center in Tucson Arizona, and featured contributor
to IBM's developerWorks. In 2016, Tony celebrates his 30th year anniversary with IBM Storage. He is
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.
(Short URL for this blog: ibm.co/Pearson )
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Continuing my coverage of the annual [2010 System Storage Technical University], I participated in the storage free-for-all, which is a long-time tradition, started at SHARE User Group conference, and carried forward to other IT conferences. The free-for-all is a Q&A Panel of experts to allow anyone to ask any question. These are sometimes called "Birds of a Feather" (BOF). Last year, they were called "Meet the Experts", one for mainframe storage, and the other for storage attached to distributed systems. This year, we had two: one focused on Tivoli Storage software, and the second to cover storage hardware. This post provides a recap of the Storage Hardware free-for-all.
The emcee for the event was Scott Drummond. The other experts on the panel included Dan Thompson, Carlos Pratt, Jack Arnold, Jim Blue, Scott Schroder, Ed Baker, Mike Wood, Steve Branch, Randy Arseneau, Tony Abete, Jim Fisher, Scott Wein, Rob Wilson, Jason Auvenshine, Dave Canan, Al Watson, and myself, yours truly, Tony Pearson.
What can I do to improve performance on my DS8100 disk system? It is running a mix of sequential batch processing and my medical application (EPIC). I have 16GB of cache and everything is formatted as RAID-5.
We are familiar with EPIC. It does not "play well with others", so IBM recommends you consider dedicating resources for just the EPIC data. Also consider RAID-10 instead for the EPIC data.
How do I evaluate IBM storage solutions in regards to [PCI-DSS] requirements.
Well, we are not lawyers, and some aspects of the PCI-DSS requirements are outside the storage realm. In March 2010, IBM was named ["Best Security Company"] by SC Magazine, and we have secure storage solutions for both disk and tape systems. IBM DS8000 and DS5000 series offer Full Disk Encryption (FDE) disk drives. IBM LTO-4/LTO-5 and TS1120/TS1130 tape drives meet FIPS requirements for encryption. We will provide you contact information on an encryption expert to address the other parts of your PCI-DSS specific concerns.
My telco will only offer FCIP routing for long-distance disk replication, but my CIO wants to use Fibre Channel routing over CWDM, what do I do?
IBM XIV, DS8000 and DS5000 all support FC-based long distance replication across CWDM. However, if you don't have dark fiber, and your telco won't provide this option, you may need to re-negotiate your options.
My DS4800 sometimes reboots repeatedly, what should I do.
This was a known problem with microcode level 760.28, it was detecting a failed drive. You need to replace the drive, and upgrade to the latest microcode.
Should I use VMware snapshots or DS5000 FlashCopy?
VMware snapshots are not free, you need to upgrade to the appropriate level of VMware to get this function, and it would be limited to your VMware data only. The advantage of DS5000 FlashCopy is that it applies to all of your operating systems and hypervisors in use, and eliminates the consumption of VMware overhead. It provides crash-consistent copies of your data. If your DS5000 disk system is dedicated to VMware, then you may want to compare costs versus trade-offs.
Any truth to the rumor that Fibre Channel protocol will be replaced by SAS?
SAS has some definite cost advantages, but is limited to 8 meters in length. Therefore, you will see more and more usage of SAS within storage devices, but outside the box, there will continue to be Fibre Channel, including FCP, FICON and FCoE. The Fibre Channel Industry Alliance [FCIA] has a healthy roadmap for 16 Gbps support and 20 Gbps interswitch link (ISL) connections.
What about Fibre Channel drives, are these going away?
We need to differentiate the connector from the drive itself. Manufacturers are able to produce 10K and 15K RPM drives with SAS instead of FC connectors. While many have suggested that a "Flash-and-Stash" approach of SSD+SATA would eliminate the need for high-speed drives, IBM predicts that there just won't be enough SSD produced to meet the performance needs of our clients over the next five years, so 15K RPM drives, more likely with SAS instead of FC connectors, will continue to be deployed for the next five years.
We'd like more advanced hands-on labs, and to have the certification exams be more product-specific rather than exams for midrange disk or enterprise disk that are too wide-ranging.
Ok, we will take that feedback to the conference organizers.
IBM Tivoli Storage Manager is focused on disaster recovery from tape, how do I incorporate remote disk replication.
This is IBM's Unified Recovery Management, based on the seven tiers of disaster recovery established in 1983 at GUIDE conference. You can combine local recovery with FastBack, data center server recovery with TSM and FlashCopy manager, and combine that with IBM Tivoli Storage Productivity Center for Replication (TPC-R), GDOC and GDPS to manage disk replication across business continuity/disaster recovery (BC/DR) locations.
IBM Tivoli Storage Productivity Center for Replication only manages the LUNs, what about server failover and mapping the new servers to the replicated LUNs?
There are seven tiers of disaster recovery. The sixth tier is to manage the storage replication only, as TPC-R does. The seventh tier adds full server and network failover. For that you need something like IBM GDPS or GDOC that adds this capability.
All of my other vendor kit has bold advertising, prominent lettering, neon lights, bright colors, but our IBM kit is just black, often not even identifying the specific make or model, just "IBM" or "IBM System Storage".
IBM has opted for simplified packaging and our sleek, signature "raven black" color, and pass these savings on to you.
Bring back the SHARK fins!
We will bring that feedback to our development team. ("Shark" was the codename for IBM's ESS 800 disk model. Fiberglass "fins" were made as promotional items and placed on top of ESS 800 disk systems to help "identify them" on the data center floor. Unfortunately, professional golfer [<a href="http://www.shark.com/">Greg Norman</a>] complained, so IBM discontinued the use of the codename back in 2005.)
Where is Infiniband?
Like SAS, Infiniband had limited distance, about 10 to 15 meters, which proved unusable for server-to-storage network connections across data center floorspace. However, there are now 150 meter optical cables available, and you will find Infiniband used in server-to-server communications and inside storage systems. IBM SONAS uses Infiniband today internally. IBM DCS9900 offers Infiniband host-attachment for HPC customers.
We need midrange storage for our mainframe please?
In addition to the IBM System Storage DS8000 series, the IBM SAN Volume Controller and IBM XIV are able to connect to Linux on System z mainframes.
We need "Do's and Don'ts" on which software to run with which hardware.
IBM [Redbooks] are a good source for that, and we prioritize our efforts based on all those cards and letters you send the IBM Redbooks team.
The new TPC v4 reporting tool requires a bit of a learning curve.
The new reporting tool, based on Eclipse's Business Intelligence Reporting Tool [BIRT], is now standardized across the most of the Tivoli portfolio. Check out the [Tivoli Common Reporting] community page for assistance.
An unfortunate side-effect of using server virtualization like VMware is that it worsens management and backup issues. We now have many guests on each blade server.
IBM is the leading reseller of VMware, and understands that VMware adds an added layer of complexity. Thankfully, IBM Tivoli Storage Manager backups uses a lightweight agent. IBM [System Director VMcontrol] can help you manage a variety of hypervisor environments.
This was a great interactive session. I am glad everyone stayed late Thursday evening to participate in this discussion.
This week I was aboard the Queen Mary in Long Beach, California! This was a business event organized by [Key Info Systems], a valued IBM Business Partner. Key Info resells IBM servers, storage and switches.
The Queen Mary retired in 1967, and has been converted into a hotel and events venue. The locals just parked their car and walked on board, but I got to stay Tuesday through Thursday in one of the cabins. It was long and narrow, with round windows! There were four dials for the bathtub: Cold Salt, Hot Fresh, Cold Fresh, and Hot Salt.
Stepping on the boat was like walking back in time through history! If you decide to go see it, check out the [Art Deco bar at the front of the Promenade deck. The ship is still in the water, but is permanently docked. It is sectioned off to prevent the ocean waves from affecting it, so we did not have the nauseous moving back and forth normally associated with cruise ships.
(It is with a bit of irony that we are on the Queen Mary just days after the tragedy of the [Costa Concordia], the largest Italian cruise ship that ran aground near Isola de Giglio. The captain will have to explain how he [fell into a lifeboat] before he had a chance to wait for everyone else to get safely off the shipwreck. He was certainly no [Captain Sulley]! I am thankful that most of the 4,200 people survived the incident.)
Lief Morin, Founder and Chief Executive for Key Info Systems, kicked off the meeting with highlights of 2011 successes. I have known Lief for years, as Key Info comes to the Tucson EBC on a frequent basis. This event was designed to give his sellers an update of what is the latest for each product line, and what to look forward to in the next 12-18 months.
The next speaker was from Vision Solutions that provides High Availability solutions for IBM i on Power Systems. In 2010, their company nearly doubled in size with the acquisition of Double-Take, which provides data replication for x86 servers running Windows, Linux, VMware, Hyper-V and other hypervisors. The capabilities of Double-Take sounded similar to what IBM offers with [Tivoli Storage Manager FastBack] and [Tivoli Storage Manager for Virtual Environments].
Dinner at Sir Winston's
Rather than take the "Ghosts and Legends" tour, I opted for dinner at the Queen Mary's signature restaurant, Sir Winston's. This is a fancy place, so dress accordingly. If you want the Raspberry soufflé, order it early as it takes 30 minutes to prepare!
[Storwize V7000], including the new Storwize V7000 Unified configuration
Storage is an important part of the Key Info Systems revenue stream, so I was glad to have lots of questions and interactions from the audience.
Murder Mystery Dinner
The acting troupe from [Dinner Detective] put on quite the show for us! With all that is going on in the world, it is good to laugh out loud every now and then.
In other murder mystery dinners I have participated in, each person is assigned a "character" and given a script of what to say and when to say it. This was different, we got to pick our own characters. I chose "Doctor Watson", from the Sherlock Holmes series. Several attendees thought it was a double meaning with [IBM Watson], the computer that figured out the clues on Jeopardy! television game show, and has since been [put to work at Wellpoint] to help out the Healthcare industry.
After the "murder" happened, two actors portraying policemen selected members of the audience to answer questions. We didn't get a script of what to say, so everyone had to "ad lib". I was singled out as a suspect, and had fun playing along in character. One of the attendees afterwards said he was impressed that I was able to fabricate such amusing and elaborate responses to their personal and embarassing questions. As a public speaker for IBM, I have had a lot of practice thinking quickly on my feet.
Fibre Channel and Ethernet Switches
The next two speakers gave us an update on Fibre Channel and Ethernet switches, and their thoughts on the inevitability of Fibre Channel over Ethernet (FCoE). One of the exciting new developments is the [Brocade Network Subscription] which creates a flexible pay-per-use Ethernet port rental model for customers. This is especially timely given the Financial Accounting Standards Board proposed [FASB Change 13] that affects operating leases in the balance sheet.
With the Brocade Network Subscription, you pay monthly for the ports you are using. Need more ports, Brocade will install the added gear. Use fewer ports, Brocade will take the equipment back. There is no term endpoint or residual value like tradtional leasing, so when you are done using the equipment, give it back any time. This is ideal for companies that may need to have a lot of Ethernet ports for the next 2-3 years, but then plan to taper down, and don't want to get stuck with a long-term commitment or capital depreciation.
The last speaker was from VMware. IBM is the #1 reseller of VMware, and VMware commands an impressive 81 percent marketshare in the x86 virtualization space. The speaker presented VMware's strategy going forward, which aligns well with IBM's own strategy, to help companies Cloud-enable their existing IT infrastructures, in preparation for eventual moves to Hybrid or Public cloud deployments.
Special thanks to Lief Morin for sponsoring this event, Raquel Hernandez from IBM for coordinating my travel, and Pete, Christina and Kendrell from Key Info Systems for organizing the activities!
Continuing my coverage of the [IBM System x and System Storage Technical Symposium], I thought I would start with some photos. I took these with cell phone, and without realizing how much it would cost, uploaded them to Flickr at international data roaming rates. Oops!
Here are some of the banners used at the conference. Each break-out session room was outfitted with a "Presentation Briefcase" that had everything a speaker might need, including power plug adapters and dry-erase markers for the whiteboard. What a clever idea!
Here is a recap of the last and final day 3:
Understanding IBM's Storage Encryption Options
Special thanks to Jack Arnold for providing me his deck for this presentation. I presented IBM's leadership in encryption standards, including the [OASIS Key Management Interoperability Protocol] that allows many software and hardware vendors to interoperate. IBM offers the IBM Tivoli Key Lifecycle Manager (TKLM v2) for Windows, Linux, AIX and Solaris operating systems, and the IBM Security Key Lifecycle Manager (v1.1) for z/OS.
Encrypting data at rest can be done several ways, by the application at the host server, in a SAN-based switch, or at the storage system itself. I presented how IBM Tivoli Storage Manager, the IBM SAN32B-E4 SAN switch, and various disk and tape devices accomplish this level of protection.
NAS @ IBM
Rich Swain, IBM Field Technical Sales Specialist for NAS solutions, provided an overview of IBM's NAS strategy and the three products: Scale-Out Network Attached Storage (SONAS), Storwize V7000 Unified, and N series.
IBM System Networking Convergence CEE/DCB/FCoE
Mike Easterly, IBM Global Field Marketing Manager for IBM System Networking, presented on Network convergence. He wants to emphasize that "Convergence is not just FCoE!" rather it is bringing together FCoE with iSCSI, CIFS, NFS and other Ethernet-based protocols. In his view, "All roads lead to Ethernet!"
There are a lot new standards that didn't exist a few years ago, such as PCI-SIG's Single Root I/O Virtualization [SR-IOV], Virtual Ethernet Port Aggregator [VEPA], and [VN-Tag], Data Center Bridging [DCB], Layer-2 Multipath [L2MP], and my favorite: Transparent Interconnect of Lots of Links [TRILL].
Last year, IBM acquired Blade Network Technologies (BNT), which was the company that made IBM BladeCenter's Advanced Management Module (AMM) and BladeCenter Open Fabric Manager (BOFM). BNT also makes Ethernet switches, so it has been merged with IBM's System Storage team, forming the IBM System Storage and Networking team. Most of today's 10GbE is either fiber optic, Direct Attach Copper (DAC) that supports up to 8.5 meter length cables, or 10GBASE-T which provides longer distances of twisted pair. IBM's DS3500 uses 10GBASE-T for its 10GbE iSCSI support.
Last month, IBM announced 40GbE! I missed that one. The IT industry also expects to deliver 100GbE by 2013. For now, these will be used as up-links between other switches, as most servers don't have the capacity to pump this much data through their buses. With 40GbE and 100GbE, it would be hard to ignore Ethernet as the common network standard to drive convergence.
Fibre Channel, such as FCP and FICON, are still the dominant storage networking technology, but this is expected to peak around 2013 and start declining thereafter in favor of iSCSI, NAS and FCoE technologies. Already the enhancements like "Priority-based Flow Control" made to Ethernet to support FCoE have also helped out iSCSI and NAS deployments as well.
The iSCSI protocol is being used with Microsoft Exchange, PXE Boot, Server virtualization hypervisors like VMware and Hyper-V, as well as large Database and OLTP. IBM's SVC, Storwize V7000, XIV, DS5000, DS3500 and N series all support iSCSI.
IBM's [RackSwitch] family of products can help offload traffic at $500 per port, compared to traditional $2000 per port for IBM SAN32B or Cisco Nexus5000 converged top-of-rack switches.
IBM's System Networking strategy has two parts. For Ethernet, offer its own IBM System Networking product line as well as continue its partnership with Juniper Networks. For Fibre Channel and FCoE, continue strategic partnerships with Brocade and Cisco. IBM will lead the industry, help drive open standards to adopt Converged Enhanced Ethernet (CEE), provide flexibility and validate data center networking solutions that work end-to-end.
A lot was announced yesterday, so I decided to break it up into several separate posts. This is part 2 in my 3-part series, focusing on: Storwize V7000 Unified, LTO-6 tape, and the SmartCloud Virtual Storage Center.
The Storwize V7000 Unified is a product that consists of a 2U-high Storwize V7000 control enclosure that provides block-based access, combined with two 2U-high File Modules that provide file-based NAS protocols: CIFS, NFS, HTTPS, SCP and FTP. The problem was that when it was introduced, it was based on Storwize V7000 v6.3, so when the Storwize V7000 v6.4 features were announced last June, they did not apply to the Storwize V7000 Unified.
That is all fixed now, so the Storwize V7000 Unified now supports the full v6.4 features, including Real-time Compression for both file and block-based access to primary data, and Fibre Channel over Ethernet (FCoE) for block access.
The two File Modules are no longer limited to a single Storwize V7000 control enclosure, you can now connect to up to four control enclosures clustered together. Combined with up to nine expansion enclosures for additional disk raises the total maximum to 960 drives.
If you don't already have an Active Directory or LDAP server, the Storwize V7000 Unified now offers an embedded LDAP server, for smaller deployments that want to reduce the number of servers they need to purchase for a complete solution.
Like the [IBM XIV Gen3 storage system], both the Storwize V7000 and V7000 Unified now also support the OpenStack Nova-volume interface.
Lastly, if you have a Storwize V7000 v6.4, you can upgrade it to a Storwize V7000 Unified by simply adding the two File Modules. This can be done in the field.
IBM LTO-6 for tape libraries and drives
IBM introduces the sixth generation of Linear Tape Open (LTO-6) drives, which can be used as stand-alone IBM TS1060 drives, or in IBM tape libraries. As with previous models of LTO, the LTO-6 can read two older generations (LTO-4 and LTO-5) tape media, and can write to previous generation (LTO-5) tape media. You can buy the LTO-6 drives now, and use the older media until LTO-6 tape cartridges are available (hopefully later this year!)
My friend, Brad Johns, from Brad Johns Consulting, has a great post on this [LTO-6 Announcement]. While you expect the new drives to be faster with a denser tape media format, the key advantage to the LTO-6 is that it improves the compression algorithm, from the previous 2:1 to the new 2.5:1 compression ratio:
Thus, with the improved compression, the LTO-6 is 40 percent faster, with double the tape cartridge density. This can reduce backup times by 30 percent, increase the amount of data that sits in your automated tape libraries, and reduce the courier costs sending tapes off-site.
IBM SmartCloud Virtual Storage Center v5.1
Last year, IBM coined the phrase "Storage Hypervisor" to refer to the underlying technology in the IBM SAN Volume Controller (SVC) and Storwize V7000 disk systems.
At the IBM Edge conference last June, my colleague Mike Griese presented [SmartCloud Virtual Storage Center]. Back then, it was a pilot program (beta test), and this week, IBM announces that it will be formally available as a product.
The idea was simple: take the basic storage hypervisor, and add the necessary software to make it a complete solution.
If all of your disk is currently virtualized behind IBM SAN Volume Controller (SVC), or you want to put all of your data behind SVC, then SmartCloud Virtual Storage Center is for you. Basically, for one per-TB price, you get all of the following:
The software features of SAN Volume Controller v6.4, including FlashCopy, Metro Mirror and Global Mirror.
The full advanced features of IBM Tivoli Storage Productivity Center v5.1, including the Storage Analytics Engine that does "Right-Tiering", recommending which LUNs should be moved entirely from one disk system to another, based on policies and access patterns.
IBM Tivoli Storage FlashCopy Manager v3.2 which manages FlashCopy with full coordination with applications, including Microsoft Exchange, SQL Server, DB2, Oracle, SAP, and VMware. This ensures that the FlashCopy destination copies are clean, eliminating the need to run backout or redo logs to correct any incomplete units of work.
If this combination sounds familiar, it was based on IBM's previous attempt called [Rapid Application Storage] which combined the Storwize V7000 with Tivoli Storage Productivity Center Midrange Edition and FlashCopy Manager.
The key difference is that SmartCloud VSC does not include the SVC hardware itself, you buy this separately. If you want Real-time Compression, that is charged separately for the subset of TB of the volumes that you select for compression.
I always try to catch a session from Jim Blue, who works in our "SAN Central" center of competency team. This session was a long list of useful hints and tips, based on his many years of experience helping clients.
SAN Zoning works by inclusion, limiting the impact of failing devices. The best approach is to zone by individual initiator port. The default policy for your SAN zoning should be "deny".
Ports should be named to identify who, what, where and how.
While many people know not to mix both disk and tape devices on the same HBA, Jim also recommends not mixing dissimilar disks, test and production, FCP and FICON.
The sweet spot is FOUR paths. Too many paths can impact performance.
When making changes to redundant fabrics, make changes to the first fabric, then allow sufficient time before making the same changes to the other fabric.
Use software tools like Tivoli Storage Productivity Center (Standard Edition) to validate all changes to your SAN fabric.
Do not mix 62.5 and 50.0 micron technology.
Use port caps to disable inactive ports. In one amusing anecdote, he mention that an uncovered port was hit by sunlight every day, sending error messages that took a while to figure out.
Save your SAN configuration to non-SAN storage for backup
Consider firmware about two months old to be stable
Rule of thumb for estimating IOPS: 75-100 IOPS per 7200 RPM drive, 120-150 IOPS per 10K RPM drive, and 150-200 IOPS per 15K RPM drive.
Decide whether your shop is just-in-time or just-in-case provisioning. Just-in-time gets additional capacity on demand as needed, and just-in-case over-provisions to avoid scrambling last minute.
Avoid oversubscribing your inter-switch links (ISL). Aim for around 7:1 to 10:1 ratio.
Don't go cheap on bandwidth between sites for long-distance replication
Next Generation Network Fabrics - Strategy and Innovations
Mike Easterly, IBM Director of Global Field Marketing, presented IBM System Networking strategy, in light of IBM's recent acquisition of Blade Network Technologies (BNT). BNT is used in 350 of the Fortune 500 companies, and is ranked #2 behind Cisco in sales of non-core Ethernet switches (based on number of units sold).
Based on a recent survey, companies are upgrading their Ethernet networks for a variety of reasons:
56 percent for Live Partition Mobility and VMware Vmotion
45 percent for integrated compute stacks, like IBM CloudBurst
43 percent for private, public and hybrid cloud computing deployments
40 percent for network convergences
Many companies adopt a three-level approach, with core directors, distribution switches, and then access switches at the edge that connect servers and storage devices. IBM's BNT allows you to flatten the network to lower latency by collapsing the access and distribution levels into one.
IBM's strategy is to focus on BNT for the access/distribution level, and to continue its strategic partnerships for the core level.
IBM BNT provides better price/performance and lower energy consumption. To help with hot-aisle/cold-aisle rack deployments, IBM BNT provides both F and R models. F models have ports on the front, and R models have ports in the rear.
IBM BNT supports virtual fabric and HW-offload iSCSI traffic, and future-enabled for FCoE. Support for TRILL (transparent interconnect of lots of links) and OpenFlow will be implemented through software updates to the switches.
While Cisco Nexus 1000v is focused on VMware Enterprise Plus, IBM BNT's VMready works with VMware, Hyper-V, Linux KVM, XEN, OracleVM, and PowerVM. This allows single pane of management of VMready and ESX vSwitches.
In preparation for Converged Enhanced Ethernet (CEE), IBM BNT will provide full 40GbE support sometime next year, and offer switches that support 100GbE uplinks. IBM offers extended length cables, including passive SFP+ DAC at 8.5 meters, and 10Gbase-T Cat7 cables up to 100 meters.
Inter-datacenter Workload Mobility with VMware vSphere and SAN Volume Controller (SVC)
This session was co-presented between Bill Wiegand, IBM Advanced Technical Services, and Rawley Burbridge, IBM VMware and midrange storage consultant. IBM is the leader in storage virtualization product (SVC), and is the leading reseller of VMware.
Like MetroCluster on IBM N series, or EMC's VPLEX Metro, the IBM SAN Volume Controller can support a stretched cluster across distance that allows virtual machines to move seamlessly from one datacenter to another. This is a feature IBM introduced with SVC 5.1 back in 2009. This can be used for PowerVM Live Partition Mobility, VMware vMotion, and Hyper-V Quick Migration.
SVC stretched cluster can help with both Disaster Avoidance and Disaster Recovery. For Disaster Avoidance, in anticipation of an outage, VMs can be moved to the secondary datacenter. For Disaster Recover, additional automation, such as VMware High Availability (HA) is needed to restart the VMs at the secondary datacenter.
IBM stretched cluster is further improved with a feature called Volume Mirroring (formerly vDisk Mirroring) which creates two physical copies of one logical volume. To the VMware ESX hosts, there is only one volume, regardless of which datacenter it is in. The two physical copies can be on any kind of managed disk, as there is no requirement or dependency of copy services on the back-end storage arrays.
Another recent improvement is the idea of spreading the three quorum disks to three different locations or "failure domains". One in each data center, and a third one in a separate building, somewhere in between the other two, perhaps.
Of course, there are regional disasters that could affect both datacenters. For this reason, SVC stretched cluster volumes can be replicated to a third location up to 8000 km away. This can be done with any back-end disk arrays, as again there is not requirement for copy services from the managed devices. SVC takes care of it all.
Networking is going to be very important for a variety of transformational projects going forward in the next five years.