Advantages of AS/400

130 pts.
IBM iSeries
Hi, Please let me know the Advantages of AS/400 when compared to Windows, Unix servers. Regards S.Manjunath

Answer Wiki

Thanks. We'll let you know when a new response is added.

Here is a great blog post on a comparison with a linux cluster servers from the iSeries blog.

Discuss This Question: 16  Replies

There was an error processing your information. Please try again later.
Thanks. We'll let you know when a new response is added.
Send me notifications when members answer or reply to this question.
  • BrentSheets
    Moderator Note: Hi Accenture. Your question is very broad and you may not receive many replies. If there is a specific area of how AS/400 stacks up against Windows and Unix that you're concerned with, then feel free to click "Add to Discussion" and provide more information. Thanks.
    6,950 pointsBadges:
  • Lovemyi
    There are many reasons to pick the IBM i over AIX, UNIX, LINUX and Windows from a pure business reason. For starters, it is the reliability that makes the IBM i platform still the best buisness machine for over 30 years. The fuily integrated database (DB2 compliant), integrated security, full system logging via journals that cannot be comprimised. This is why the IBM i is the only C2 Goverment rated securable machine on the planet. Uptime reliablilty unmatched except by the largest of mainframes. Total cost of ownership is less than most platforms for major application like ERP and Bank applications due to it's ease of use and fully integrated yet very open proprietory OS. It can run Unix in an emulation environment and can host a LINUX partition as well on the IBM i OS. Everyone is still trying to emulate the best parts of the IBM i today, like VMWARE is being used to do what the system has been doing for over 30 years with running multiple applications at the same time and a whole host of other features that other systems are either starting to copy or are doing but none of them have the complete package like the IBM i, System i, iSeries, AS/400, System/38 or what ever they call the platform tomorrow. Lovemyi
    2,310 pointsBadges:
  • TheHeck
    The AS400/I-series/System I is one of the most reliable and stable platforms out there. The AS400 is the technological backbone of many large (and small) companies running any number of applications. Simply put, it's like that 1985 Chevy that starts on a cold winter morning and gets you to where you need to go... It may not be as pretty or as fashionable as some other systems, but performs with very little maintenance.
    165 pointsBadges:
  • WoodEngineer
    The reason we stay with the AS/400 or what ever you want to call it. Very reliable. Secure. A totally integrated system. By that I mean you don't have to buy the OS one place, backup software somewhere else and go to a third source for the database. There are tons more items than I could possibly list. related to the integrated OS. Best cost of ownership in the business. Windows servers may be cheaper on initial purchase but you've got ot have one for every little thing, which is vary annoying. Also, WinTel boxes require a lot of care a feeding. We spend very little time keeping our i Series running which allows us to focus on the business applications. The time one spends keeping a system alive is pretty much wasted time as far as doing jobs that add value to the company. Software developed on the AS/400 just keeps on running year after year. I'm running some handy utilities developed in the 1980's. Have not had to touch them in all these years and after many operating system upgrades. Plus, I like to sleep at night.
    8,235 pointsBadges:
  • azohawk

    I will agree with what the others have added and I will add that I have seen smaller staffs to manage the iSeries compared to the others. In my past 3 positions I have been the primary (a single parttime backup person) or only person doing the work for the system. That includes administration, database management, coding, fixes, help line, you name (user sharing websites like this have been a huge help).  While in these positions, there have been 2-6 others in the department to manage windows, the server farm and network services. Other functions were typically hired out.

    Anywhere I have worked, we have managed w/ a single system.

    Everything is in one box. easier to manage, fewer issues when something doesn't work of the round robin blame game.

    IBM support has been fantastic.  (I reported a problem one time that IBM pretty much stated "we don't have a clue", we came up w/ a workaround and moved on. Six months later, got a call from IBM "we found the source of the problem, don't know how to fix it yet, but we found the source". With that info, I was able to investigate more can found the solution). How many of these others would remember to notify you 6 months later?

    Upgrade hardware, OS, etc. I don't have to worry about my programs running in most cases (and IBM makes a big deal about it if you might have to).

    Less downtime. My previous employment was having frequent issues during production hours with other systems. (I won't say never but very rare with the iSeries.)

    Security, reliability, compatibility have all been discussed but I have to say they are go to reasons.

    4,065 pointsBadges:
  • ButterleyPark
    Whilst I would agree with the many descritpions of how reliable and secure iSeries machines are, I should also add that they may not be the preferred choice if you are looking for a blistering database performance, or ease of implementation for a distributed system. My experience of them has been that they are a bit ponderous when executing queries against large data sets, and communications between different machines can be rather complex to set up and maintain.
    20 pointsBadges:
  • TheRealRaven
    @ButterleyPark: Any individual's experiences might be similar to yours, but many others will disagree. And what you say can be said about any competitive system except specialty systems, such as ones specifically designed for database performance.
    36,860 pointsBadges:
  • aceofdelts

    More good points are ...

    it scales up well - you can start with a 4-user system and the same programs can handle a 1,000 user system

    Operating system is backwards-compatible. IBM has never (I think) released a new version that causes an existing function to fail

    2,550 pointsBadges:
  • ToddN2000
    I see the main pluses as speed, security and scalability.
    136,240 pointsBadges:
  • philpl1jb
    ROI - we have 30 year old code running exactly as it was written with a brand new version of the hardware and OS.
    54,090 pointsBadges:
  • CharlieBrowne

    In reply to ButterlyPark.

    I worked at AT&T and they had the largest AS400 setup in the USA. They were over 20 different machines. The production data was spread over 6 different machines. Communication between machines was not an issue at all. We also had over 200 different places were we send and/or received data.

    The speed issue you talk about may occur when using older techniques instead of SQL for your data pulls.

    62,385 pointsBadges:
  • ButterleyPark
    In reply to TheRealRaven and CharlieBrowne.

    You may be right - my comments were based on emprical experience of a small number of use cases. Whilst I have a great deal of experience of Wintel/Linux/Java/RDBMS environments, my exposure to iSeries platforms is limited to a few months and a small number of applications.

    I run manual SQL queries from time to time against a database of 15-20 million records (small by enterprise standards!) on one of our iSeries machines, and I have been a bit surprised that these queries can take 40-50 seconds to execute. From previous experience on other platforms I would have expected these queries to take no more than 5-10 seconds, even on an unoptimised database. I have also been looking at some improvements in the applications, and we have one validation routine that would benefit from querying data held on another iSeries machine on the same network. When I suggested this to our (experienced!) RPG developers, there was a collective sharp intake of breath, and a lot of resistance to the idea "because it is difficult".

    So in summary, I would agree that the platform is absolutely bomb-proof and secure; my limited experience has shown that our implementation is kinda slow executing queries and our developers seem to think that remote queries are the work of the devil. This is a shop that has been using the AS400/iSeries platform for years, so I would have expected them to be reasonably comfortable with it, but maybe not? Perhaps it's just us!
    20 pointsBadges:
  • TheRealRaven
    @ButterlyPark: That sounds reasonable. A 40-50 second response time would also irritate me, and I see similar on various systems. Unfortunately (for them?), I'm rarely in a position to effect change since I'm involved in non-DB work. So, they usually remain with the database designs (and file attributes) that reflect from 30 years ago, before SQL was usually available.

    It's hard to convince groups that they've been doing things.... ummm... not 'right'... when you have them as customers in a different area.

    And many(!) RPG developers are far from knowing DBMS or comm details. I see many who find it difficult just to code a CL module to bind into their program. It seems easier to them to code a bunch or RPG to implement stuff like MONMSG that's already built into CL. Or trying just to convince to use host names for remote printer configurations rather than hard-coding addresses... even some simple things outside of RPG are treated as "Advanced".

    So, I see where you're coming from. It's not exactly the platform, though. It's the difficulty in expanding the experience of many who work on them. It often seems like the organizations that resist training, or merely avoid helping to advance. (And also maybe unfortunately, the platform keeps plugging along sometimes even when misconfigured.)

    I'd like to see forums like this one do some small part in fixing that. That's why I started posting here.
    36,860 pointsBadges:
  • ToddN2000
    I found a "fix" for the long access times when using SQL on an i-Series DB. I was an RPG coder for 30+ yrs and now work in the .NET world for the same company. I still have limited access to the RPG side so I get to play around a bit. Recently for a web app, I was helping another developer, we wanted to look up sales info based on the serial number bar code. The database is approx 18 million records and was taking about 25 to 30 seconds to return results. Not acceptable. In my past experience, I created a new LF on the i-Series with the serial# being the primary key, one did not exist prior to this, although there were 15 other LF's. Once it was created the SQL now runs on average 2 to 3 seconds. A big improvement and now usable.

    Granted in some environments there is no training, or you just maintain existing code. If it was written using old methods that's the way they wanted it fixed. This way everyone can read and understand it. Because of this no new knowledge is learned.

    Sometime it goes to waste. An example of this is I was sent to take some Java classes years ago and we never used one piece of Java. So why send me to the classes ?
    136,240 pointsBadges:
  • IanSimmons
    @ButterflyPark: On the performance issue - if your table doesn't have an appropriate index, you'll get a table scan and poor performance. Also, depending on your OS level, your query may still be using the older query engine (CQE Classic Query Engine) instead of the newer (SQE, of SQL Query Engine) for particular kinds of query - e.g. with the LIKE predicate. If it's used, CQE generally performs less well.

    As an example, we have one table of 142M rows. There are something like 30 indexes on this table. if I query using a SELECT column that is indexed, I get a response in less than a second - unless I add an ORDER BY clause that isn't indexed. What's more, we are still on the old V5R4 release. version 7.1 is supposed to be better.

    You can also use the Index Advisor in the Navigator tool - careful, as it suggest far too much - as an aid to find out what indexes may help, though I find you can usually guess what the index should be.

    As for the benefits of the IBM i, I have worked with various incarnations of this machine for a very long time. In all the companies I've worked for, we've only ever used one or two people to manage the machines, and rarely had more than two or three of them. Currently we have NO ONE who manages ours as a full-time job, and we have to share duties of there ever is an issue. we have no DB administrator, we just don't need one - we just need to keep an eye on overall disk space usage and run purges from time to time.The database is easy to understand, no attaching / detaching, tablespaces, memory allocation, no contention with the OS - it is integrated, after all. Only the occasional reorganisation if many rows are deleted, but even then only if you want to shrink table sizes (SQL tables reuse deleted space by default).

    Our infrastructure team on the other hand has many people to manage the multiplicity of Windows servers which invariably only ever do ONE THING each and need rebooting regularly (once a day is a good rule of thumb for Windows). 

    On the i, we have new code, very old code, all running happily side-by-side, on a system that has no actual downtime except the once-a-week full back-up that we like to do.

    Troubleshooting is easy, the logging options are second to none. 
    On the downside, it isn't pretty. But so what?
    185 pointsBadges:
  • Yorkshireman
    An obvious place to look is at and pick up some of the white papers they republish from independant reviews on cost of ownership and so forth  
    6,085 pointsBadges:

Forgot Password

No problem! Submit your e-mail address below. We'll send you an e-mail containing your password.

Your password has been sent to:

To follow this tag...

There was an error processing your information. Please try again later.

Thanks! We'll email you when relevant content is added and updated.


Share this item with your network: