IBM External Storage

Why External Storage Makes Dollars and Sense for IBM i

IBM i can make use of internal disk in your Power system or external disk through a SAN.  For years, IBM i shops have relied on internal storage because of the simplicity and the cost savings.  As time marches on, we have to reconsider our approach to things and see if what once was a good fit makes sense now.

External storage offers a ton of value. 


With features like FlashCopy, hardware replication, and Easy Tier, you can implement a solution that reduces your downtime and improves the efficiency of your data processing—resulting in actual savings for your business.

Converged Storage

With an internal disk on IBM i, you can’t share the disk amongst other platforms. With an IBM FlashSystem, you have the opportunity to have a single platform for all your storage needs.  The single user interface simplifies management.  Easy Tier automatically manages your data efficiently, moving hot data to faster storage and storing long-term data on a slower, less expensive disk.

IBM FlashSystems use software-defined storage with Spectrum Virtualize. With a single interface, you can manage and maintain all of your storage.  You can even manage disparate storage on another provider’s SAN, such as HP or Dell. Bringing all your storage under one solution saves your administrators time.

According to a recent Forrester report, “The Total Economic Impact of IBM Spectrum Virtualize“, the benefits of implementing software-defined storage saves your business money. Customers who implemented Spectrum Virtualize to consolidate their storage achieved a 60% reduction in administration efforts. That’s a lot of time that can be put to use in ways that benefit your business and help it grow.

Data Reduction

Data is king, but having too much data can be expensive. Depending on your environment, adding disk can be a relatively easy task, adding a drive, for example. Or it can be more complicated and costly when you need to add expansion units before you can add drives. Better utilization of disk space means you spend less. According to the Forrester Report on Spectrum Virtualize, companies achieved a 33% improvement in utilization by reducing their data on an average of 3:1.

Not only does the solution positively improve your current disk utilization. It also provides you with the ability to save money in the future. With the average amount of storage growth at 15% per year, companies that implement Spectrum Virtualize are …

Understanding IBM External Storage Data Reduction Technology

There are a few high-valued benefits external storage can serve up to the IBM i infrastructure stack.  The one we are going to focus on today is something IBM calls “Data Reduction”.  Data reduction technology is known in the IBM Storage world as DRP or Data Reduction Pools and is the backbone for delivering three high-value tools for reducing your overall storage footprint on disk.  That means you have to buy less physical storage to support your workload, saving you some real cash money.

Let’s look at the three pieces of tech that are available with DRP to optimize your storage on disk.

  • Thin Provisioning – Allows you to define a certain amount of storage to an individual IBM i partition but only allocate the actual storage at the SAN as the partition needs it. For example, you have an IBM i partition that you want to allocate 4TB of storage to, which will be 60% utilized.  Instead of allocating all 4TB to that partition, thin provisioning tricks IBM i into thinking it has a full 4TB of storage but the SAN only physically allocates 2.4TB-ish of storage and allocates additional storage as needed.  This is highly valuable when you have many partitions.  If you had 10x of these partitions. Instead of needing 40TB+ of storage you would need 24TB’s plus, say another 10TB’s for growth.  That is a pretty big reduction in physical storage.
  • Compression – If you are in this industry and don’t know what compression is from a high level, Google it. IBM Spectrum Virtualize allows you to turn on compression, which compresses and decompresses data as it gets written/read.
  • Deduplication – reduces the overall footprint by taking duplicate blocks of data and removing them. This is great tech but due to the nature of IBM i and it mostly being used for database type workloads, this does not provide a ton of value for IBM i workloads.

DRP technology enables you to create five types of volumes for supporting your workloads.

  • Fully allocated – This type provides no storage efficiency, but the best performance, and is available for migration.
  • Thin – This type provides storage efficiency, but no compression or deduplication.
  • Thin and Compressed – This type provides storage efficiency with compression, and this combination provides the best performance numbers.
  • Thin and Deduplication – This type provides storage efficiency, but without compression.
  • Thin, Compressed, and Deduplication

Accidental Deletes on External Storage: How Volume Protection can Prevent a Disaster

If you have an IBM SAN (Storwize or FlashSystem family) then you may be familiar with the process of deleting volumes within the storage management GUI. It’s basically as simple as right-clicking on a volume and selecting “delete.” Pretty easy, but as we all know sometimes easy is dangerous. Have you ever considered what would happen if you tried to delete something that might actually be in use? IBM has thought of that, too. The delete process is a one-way trip and there are a couple of checks in place to make sure that you’re paying attention before you commit to something so drastic.…

Options for IBM Storage and POWER9

Almost three decades ago, back in 1997, IBM announced the flagship 9337 Disk Array Subsystem, a rack-mount disk unit that offers 1,084 MB to 33.55 GB of DASD for the AS/400 9406 Models B, D, E, and F as well as AS/400 Advanced System Model.  Back in the early ’80s, I engaged in a benchmark of the 9337 Disk Subsystem on an enterprise AS/400 against the EMC Symmetric system in Rochester, Minnesota.  I also presented RAID technology at a local user group meeting, explaining how to protect the data on the 9337 storage for the AS/400 with RAID 5 technology.

We have come a long way in storage for the Power System. In addition to internal hard disk drives (HDDs), there are Solid State Drives (SSDs), Non-Volatile Memory express (NVMe) drives, and the external IBM FlashSystems with all NVMe storage option. Gone are the days when AS/400 internal storage was usually the first choice in achieving the best performance. This blog discusses various IBM storage options for POWER9 and highlights the cost difference of deploying different storage options on a FlashSystem fiber attached to a POWER9.…

Costs of IBM i Storage Beyond the CEC: Expansion Drawers vs. V5030E SAN

IBM i Storage by the Numbers: Internal vs External SSD

I wrote an article on LinkedIn called “Shocking… IBM i Cost of Storage beyond the CEC: EXP-24S or V3700 SAN?” back in 2016 that sparked many conversations on what place external storage has in the IBM i hardware stack.  As a result of the popularity of my previous article, big innovation in the storage market, changes in storage costs, and a much more open IBM i infrastructure stack, it seemed like a really good time to go through the exercise again.

I don’t think it’s my place to sell you on whether internal or external storage is better.  Honestly, I believe there is a strong case to be made for both, depending on the customer situation.  With that being said I think it’s important I share my experience and knowledge, so you have what you need to make an informed decision for the businesses you serve.

For IBM i clients, typically there are a few reasons why they start to ponder a move to external storage:…

POWER9 – Which is Better: Internal or External Storage?

Most IBM i customers have an ERP package on their IBM Power server that runs their business.  Typically, a small or mid-sized company can comfortably operate with one Power9 core activation, that provides a CPW of 13,125.  The IBM Power9 model S914 has two processor options, a 4-core, and a 6-core.  Which one do you get if you only need 1 core activation?  The 4-core server is physically the same as the 6-core server, except for the processor and the other differences shown in the table below.

Feature 4-core 6-core
Maximum Cores 4 6
Maximum Memory 64GB 1TB
Maximum Internal Disk Drives 10 (283GB HDD or 387GB SSD) 672, many HDD & SSD sizes
BUS Expansion None 1 drawer – 6 adapter slots
Software Tier Group P05 P10

Let’s discuss each of these differences in more detail:…