Disaster recovery

I thought this week I’d talk about mainframe recovery following a natural or man-made disaster. It’s always an interesting and important topic.

The first thing to say is that the recovery strategy for a company should be driven by informed decisions by the board rather than by the IT department. It is the company directors who have to decide how long the company can be without IT services, how much data can be lost, and also how much money should be spent on it. This is where the IT department needs to help with the discussion – making it clear how much meeting the first two criteria will cost.

In a batch world, and yes I am old enough to remember those days, it was enough to have yesterday’s system up and running a few hours after the disaster occurred. This is quite a cheap option and for most companies is perhaps 20 years out-of-date. Nowadays, a company cannot afford to have its online system unavailable for very long at all, but how long is "long"? The company also cannot afford to lose any data, but a compromise will have to be made between cost and amount of data lost. And the IT department has to work within those constraints and with a sensible budget (also, as I said above, decided by the board).

For many organizations, the disaster recovery strategy involves having a standby mainframe supporting up to two other mainframes in a Geographically Dispersed Parallel Sysplex (GDPS) configuration. (In fact, this is called GDPS/MGM and has been available since November 2000). The big advantage of GDPS is that it is transparent to the applications running on the mainframe (CICS, DB2, etc). In an ideal world, there is no data loss, no impact on local operations, and no database recovery operations are required – however this does assume that there are no connectivity problems and that there are no write failures on the standby machine. There are, not surprisingly, some disadvantages. You need duplicate DASD, and there are also high bandwidth requirements.

GDPS makes use of Metro Mirror and Global Mirror (the MGM part of the acronym above). Metro Mirror (also called PPRC – Peer-To-Peer Remote copy) works in the following way. An application subsystem will write to a primary volume. Local site storage control will then disconnect from the channel. It will then write to a secondary volume at the remote site. Remote site storage control will then signal that the write operation is complete. Local site storage control then posts an I/O complete message. The advantage of Metro Mirror is that there is minimal host impact for performing the copy because the entire process is performed by the disk hardware. There are some disadvantages. There is a limit to the distance between the Sysplex Timers (about 25 miles if you want it quick, 180 miles if you want it at all). In some locations this might not be a problem, but in others it definitely could be. The other penalty is that DASD write times are all much longer than normal.

z/OS Global Mirror (XRC – eXtended Remote Copy) is an asynchronous methodology (Metro Mirror is synchronous). Global Mirror uses Global Copy and FlashCopy. At fixed intervals it invokes a point-in-time copy at the primary site. This doesn’t impact on local performance. Information from many volumes is then copied to the recovery site at the same time. Global Mirror allows there to be a greater distance between the main mainframe and the standby mainframe, but the data may be "old" – ie not current. On the bright side, the data may be as little as just a few seconds old. Recovery time using Global Mirror is estimated at between 30 seconds and ten minutes for applications to be automatically up and running.

Other useful parts of the GDPS family are xDR and HyperSwap. XDR is the short name for GDPS/PPRC Multiplatform Resilience for Linux for System z, which provides disaster recovery for Linux for System z users. This is particularly useful for distributed hybrid applications such as WebSphere.

HyperSwap can be used in the event of a local disk subsystem failure. The HyperSwap function is controlled by GDPS automation. HyperSwap is basically software technology that can swap in Metro Mirror devices at a secondary site replacing those at the primary site. The whole swap takes just a few seconds (ideally).

Luckily for users, GDPS works with all disk storage subsystems supporting the required levels of PPRC and XRC architectures – as well as IBM this includes disks from EMC, HDS, HP, and Sun/StorageTek. GDPS also supports Peer-to-Peer Virtual Tape Server tape virtualization technology.

Some people I have spoken to have mentioned problems with certain types of disk and GDPS, and even channel problems that have taken a while to fix. I wondered if anyone else had experienced what on the face of things seems like a very user-friendly solution to disaster recovery.

IMS products

Now just suppose that you run IMS on your mainframe, and you wonder what products are available that make using IMS easier or extend its functionality, where do you go? You could type "IMS" and "products" into Google and then search through 1,860,000 entries. But then you discover that IMS as an acronym is used for lots of different things including: Information Management System, IP Multimedia Subsystem, Institute Of Medical Sciences, Immunomagnetic separation, IMTEK Mathematica Supplement, Indianapolis Motor Speedway, Industrial Methylated Spirit, Instructional Management Systems, Insulated Metal Substrate, Integrated Micro Solutions, International Musicological Society, Internet Map Server, Internet Medieval Sourcebook, Ion mobility spectrometer, Irish Mathematical Society, Irish Marching Society, Irritable Male Syndrome (what can they mean?), Insight Meditation Society, Iowa Mennonite School, etc. (Thanks to Wikipedia for the list.)

You could try searching on "Information Management System" and "products". Just 1,720,000 hits returned for that one.

You could simply try searching your favourite software vendors’ Web sites, but that won’t give you all the products that are available that work with IMS. It will probably only tell you about ones you already knew about.

But there is a solution. Try the Virtual IMS Connection Web site’s Tools page at www.virtualims.com/tools.html. This gets regularly updated and currently lists over 50 products from ASG, Attachmate, Attunity, BMC, CA, Circle Computer Group, Compuware , CONNX Solutions, Data Kinetics, DataVantage – Direct Computer Resources, GT Software, IBM, Iona, NEON Enterprise Software, and Seagull Software. Of course, if you know of an IMS product – and I mean Information Management System, not any of those others – then get in contact with trevor@itech-ed.com.

So what products are listed? Everything from Data Kinetics’ Accelerated In-memory data access for IMS to Compuware’s Xpediter/IMS.

The other part of the Web site that’s well-worth checking out at regular intervals is the News page – it’s at www.virtualims.com/news.html. This page not only includes a short description of any new or updated IMS-related products, but it also contains a link to the original press release, so you can read the announcement in detail (including all the "tall-talking" adjectives and adjectival phrases!).

If you become a member of the Virtual IMS Connection User Group, you also get free access to the regular User Group meetings, the Newsletter, and the e-mailed "updates".

So if you are an IMS professional and you haven’t found the site yet, it’s well worth taking a look. And if you are looking for a way to extend your IMS system, then the product list is an excellent starting point. For vendors, you get a free mention in the News and Tools sections, but you could advertise elsewhere on the site.

IBM launches its zX machine

Last week IBM announced its long-awaited z10 mainframe. And it really looks like a good one.

It’s more powerful than the z9 – each box can be fitted with up to 64 purpose-built quad-core processors, so it’s 50 percent faster, delivers up to 100 percent better performance for CPU-intensive jobs, and provides 70 percent more capacity than a z9.

Internal bandwidth has doubled – support for Infiniband means support for 6GB per second (up from 2.7GB per second).

Is it "green"? IBM said that a single System z10 is the equivalent of nearly 1,500 x86 distributed servers. They also suggested it had an 85 percent smaller footprint, and 85 percent lower energy costs. In addition, IBM said that the system allows the consolidation of x86 software licences at up to a 30:1 ratio. Without knowing exactly how much this processor will really cost to buy (I mean, who pays list prices?) it’s difficult to calculate whether there is a saving over 1,500 x86 servers, and if so how much.

Is it modern? Again, IBM suggests users could run, for example, SAP on Linux with DB2 on z/OS all in one box. As shown towards the end of 2007, IBM is working with Sun to bring Solaris to the z10.

Looking at it in more detail, there’s a 991 million transistor processor, which is the quad-core processor, and it comes with 3MB of L2 cache per core. How fast is it? IBM reckons the chip can operate in excess of 4.4GHz. Also available is a separate, dedicated "service" processor, which adds 24MB of L3 cache, which can be shared by all the processor cores.

The top-end z10 processors use five quad-core die packages and two service cores, which if you do the sums comes to 20 cores at 4.4GHz, plus 60MB of L2 cache, plus 48MB of shared L3 cache on a single processor.

Wow!

Arcati Mainframe Yearbook 2008 user survey

The Arcati Mainframe Yearbook 2008 is available for download free from www.arcati.com/newyearbook08. It’s full of interesting stuff, but particularly interesting are the results of the user survey.

Only users from sites that actually had a mainframe were included in the survey results – although nine additional people who didn’t have a mainframe completed the survey! Respondents all completed a survey on the Arcati site during December 2007. 42% were from Europe and 36% from North America, with 22% from the rest of the world.
48% of the respondents worked in companies with upwards of 10,000 employees worldwide, while 21% had 1001 to 5000 staff. 11% of respondents had 0-200 staff and similarly 11% had 5001-10000. In terms of MIPS 41% of respondents (down from last year’s 47%) had fewer than 1000 MIPS installed, 30% fell into the mid-sized category between 1000 and 10,000 MIPS, and 23% were at the high end.

Looking at MIPS growth produced some interesting results. Larger, more mature businesses (above 10,000 MIPS) were mostly experiencing healthy growth – with nearly 30% in the 26-50% range. However, over 10% of sites in the 500-10,000 MIPS range were experiencing a decline, while at the same time 42% were experiencing 10-25% growth. Sites below 500 MIPS had a similarly mixed picture. Just over 28% of respondents said that their MIPS growth was static or in decline, whereas just over 28% reported growth above the 10% mark. The mainframe market does appear to be quite fragmented with competitive pressures at the lower end of the mainframe market.

Opinion is clearly divided over the role of the mainframe in new applications. Some companies regard the mainframe as a separate legacy environment while others are leveraging the strengths of large systems by using them to deploy new workloads and technologies. 48% of organizations said that their mainframes participated partly or fully in Web services. 41% say they run Java-based applications on the mainframe. Also, 68% of organizations were Web-enabling their CICS sub-systems, with 62% Web-enabling DB2.

There are a huge number of other gems of information in the survey. Comfortingly, it concludes that the "mainframe offers an increasingly cost-effective, secure, and powerful platform for companies that have the necessary background and expertise in place to support it".

Download the whole Yearbook for yourself.

The Arcati Mainframe Yearbook 2008

The 2008 edition of the celebrated Arcati Mainframe Yearbook is now available to view or download (free of charge) from www.arcati.com/newyearbook08.

It includes a mainframe strategy section with a selection of articles by industry gurus and vendors on topics such as: managing z/OS FTP, energy efficiency, using refurbished mainframes, integrating WebSphere Service Registry and Repository with WebSphere Enterprise Service Bus, cross-platform Java application performance management, using ping with CICS, and modernizing mainframe systems.

For many people the highlight each year is the mainframe user survey. This illustrates just what’s been happening at users’ sites. It’s a good way for mainframers to compare what they are planning to do with what other sites have done. I will be looking at some of the survey highlights next week.

The full vendor directory section gives contact details and other useful information in a summary format for all major vendors, consultants, and service providers in the z/OS environment.

There’s also a media guide for IBM mainframers. This lists information resources, publications, and user groups for the z/OS environment.

Next comes the glossary of terminology, which contains a large number of definitions of mainly mainframe-related terms.

The final section contains technical information – z9 model tables; mainframe hardware timeline 1952-2008; and mainframe operating system development.

In order for the Yearbook to be free, it is supported by sponsors and advertisers. This year’s sponsors were Software Diversified Services (SDS), Epoka Group A/S, Macro 4, and Iona.

To see this year’s Arcati Mainframe Yearbook, click on http://www.arcati.com/newyearbook08.

Now that the Yearbook is complete... if anyone needs a good technical writer etc, please contact me at trevor@itech-ed.com.

Data integration and mainframes

SHARE surveyed its members back in July and August 2007 and has published the results in a report entitled, The New Mainframe: Data Integration and Service-Oriented Architecture, Big Iron Style. Its 431 respondents led SHARE to conclude that, "mainframes are evolving into a leading role both as a source of mission-critical data, as well as key services". They went on to say that this "immense, scalable, real-time transaction platform for the highly-integrated environments" is needed by today’s businesses. Coming from a mainframe organization these are not startling conclusions – they just really confirm what we already knew.

Obviously, SOA (Service-Oriented Architecture) is on everyone’s mind, and the survey found that nearly one in four respondents’ organizations are currently working on SOA projects. They also found that one in three are planning or considering SOA, of which at least half will employ mainframes in a central role. The survey also found that although most SOA efforts don’t reach all the enterprise, many companies are preparing SOA to meet real-time requirements. The figures showed that about 40 percent of companies are deploying or considering event-driven architecture.

What was, perhaps, surprising was that at least half of the surveyed sites still use hand-coded scripts to move data from their mainframes to other platforms or databases. It also found that while mainframes store and manage much of their enterprise data, most of it remains inaccessible. In fact, the majority of mainframe sites share only a small portion of their data across enterprise systems.

What this clearly illustrates is the need most enterprises have for something like SOA that will make the data they store – and remember figures between 70 and 90 percent are quoted for the amount of a company’s data that is stored on a mainframe – available to non-mainframe users. Perhaps it also illustrates that SOA is not as easy to achieve as a million Powerpoint presentations suggest!

One problem that many sites face is easily identifying programs – or even parts of programs – that can be turned into Web services. Another problem is that most of the mainframe programs are written in COBOL while the Web-based programs are mainly Java. There is a big difference between the two languages and it is quite hard to convert COBOL programmers to Java programmers. A third difficulty many sites face is that their experienced COBOL programmers are getting older – with many approaching or passing retirement age.

So what technologies are enabling mainframe SOA? The survey figures were 35% application server on another platform, accessing the mainframe; 31% application server residing on the mainframe; 31% XML infrastructure devices; and 27%, composite applications on another platform, but accessing mainframe. The other options scored below 15%.

The report makes interesting reading. But it looks like mainframes and data integration with the rest of the enterprise still has some way to go.

Next week: the new Arcati Mainframe Yearbook 2008.

IBM futures – Elseworlds

If you’ve ever read DC comics – their characters are Superman, Batman, Wonder Woman, etc – you know that sometimes the authors come up with a great idea for a story featuring one of their heroes that doesn’t quite fit in with the regular continuity. So the story is published as an Elseworlds story, and we the readers can enjoy it, and regular storylines in the DC universe are not affected by it. Marvel comics run something similar under the "What If …?" tag.

So, this blog is an Elseworlds story. It looks at what could happen to IBM in the next few years – but it won’t impact on normal continuity!

So here’s the thing… what if IBM was at war with Fundamental Software (the FLEX-ES people), Hercules, and the others because it (IBM that is) was planning to release in September 2008 an Intel-based version of zVM.

You would be looking at the ultimate virtualization server – with 40 years of VM experience more than its nearest rival. Customers would have a product that might well do more work and use less power than anything else on the market. It would be a green solution. One little box (or rack) would do the work of lots of individual servers – which is the usual rational for virtualization – but this way customers get the advantage of IBM’s years of experience and IBM gets to sell more software – lots more software. And, as I’ve said before, once customers are seduced into the IBM way with small machines, they might want to get a big one – a mainframe.

zVM runs multiple operating systems concurrently, it continues even when over-utilized (they claim up to 123%), monitoring and management are well understood, it links well with Linux, it’s everything a company moving towards virtualization could want. It’s big drawback at the moment, as far as many potential customers are concerned, is that it comes on a mainframe.

Companies adopting Intel-based zVM would reduce their power consumption, their cooling costs, the amount of space the data centre takes up, and their manpower. IBM would have a runaway best seller on its hands.

On the downside, they would lose a few smaller mainframe customers to the cheaper new option, but what they’d gain is a presence in almost every medium-sized data centre, something they’ve not had since the 80s.

Like I said, it’s just an Elseworld idea.

Getting back to the real world – all you high-end IBM users with IMS installed will be pleased to hear that the second Virtual IMS Connection user group meeting takes place on Tuesday 5th February at 4:30 GMT (10:30 CST). Anyone using IMS can sign up for free membership at www.virtualims.com. The meeting is completely free, and contains a presentation by NEON’s Bill Keene on IMS disaster recovery preparation.