--- title: 400) The Database Operating System – OSAdmins | daily.dev description: A deep-dive overview of IBM i (formerly AS/400, OS/400), exploring its unique architecture that integrates a relational database (Db2 for i) directly into the... canonical: https://daily.dev/posts/400-the-database-operating-system-osadmins-nvrrsqalx twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: 400) The Database Operating System – OSAdmins | daily.dev og:description: A deep-dive overview of IBM i (formerly AS/400, OS/400), exploring its unique architecture that integrates a relational database (Db2 for i) directly into the... og:url: https://daily.dev/posts/400-the-database-operating-system-osadmins-nvrrsqalx og:image: https://api.daily.dev/og/posts/nVRrSQALx.png og:image:alt: 400) The Database Operating System – OSAdmins og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # 400) The Database Operating System – OSAdmins **[Hacker News](https://daily.dev/sources/hn)** · 43 min read · 0 upvotes · 0 comments ## Summary A deep-dive overview of IBM i (formerly AS/400, OS/400), exploring its unique architecture that integrates a relational database (Db2 for i) directly into the OS kernel. Key topics include Single Level Storage, the TIMI hardware abstraction layer enabling decades of backward compatibility, the object-based security model, Control Language (CL), the 5250 terminal interface, Integrated File System (IFS), PASE for running modern tools like Python and Node.js, work management with subsystems and jobs, backup strategies using BRMS and PTFs, High Availability via MIMIX and PowerHA, and system diagnostics. The post emphasizes that IBM i is far more than a legacy 'green screen' system, functioning as a hybrid platform capable of running both decades-old RPG applications and modern web APIs simultaneously. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Community take How the wider developer community reacted, aggregated from 1 discussion and 54 comments across hackernews (as of 2026-08-02). **TL;DR:** The HN community is broadly fascinated by IBM i/AS400's ahead-of-its-time architecture but frustrated by IBM's extreme secrecy, high costs, and the resulting talent drought; many lament that the open-source world has only partially reconstructed what IBM built decades ago. **Sentiment:** 35% positive · 40% mixed · 25% skeptical **The case for** - IBM i pioneered concepts (object-based storage, TIMI bytecode, integrated DB2, job naming) that modern stacks like k8s and cloud platforms only approximate today. - The system's deep vertical integration makes administration and reliability genuinely superior to fragmented Unix/Linux stacks. - Frank Soltis's book and a growing YouTube community (Clabretro) are making the architecture more accessible to enthusiasts. **The pushback** - IBM's extreme secrecy and high licensing/hardware costs have starved the platform of fresh talent and community growth. - The article itself is criticized as shallow and possibly AI-generated, lacking real insight into the architecture. - No emulator or freely downloadable ISO exists, making home experimentation nearly impossible and limiting the ecosystem. - IBM historically throttled its own hardware artificially to segment pricing, which commenters find cynical. **By community** - hackernews (mixed): Commenters are genuinely awed by the AS/400's design philosophy but deeply critical of IBM's walled-garden approach and skeptical of the article's quality. **Hottest debate:** Whether IBM's secrecy and licensing model is a deliberate, rational business strategy or a self-defeating mistake that killed the platform's future. **Open questions** - Could a proper open-source emulator of IBM i ever be built, given how poorly documented the system is compared to IBM Z? - How much of the AS/400's advanced architecture was actually visible and useful to everyday RPG/COBOL application developers, versus just operators? - Will IBM ever lower barriers enough (free ISOs, accessible education) to attract a new generation of IBM i developers? **Highlights** > As a youth a few decades ago I had an opportunity to play with one of these systems at home (and I actually still have it boxed up somewhere). I managed to acquire a 9401 Model 150 that fell off the back of a truck, it came with a 5250 terminal and a heavy box of documentation. Even as a kid who had started playing with linux in high school I really struggled to get it to IPL - the system was seriously weird from anything I had known before. Strangely enough, within two years of that I ended up working for IBM and went on to be trained on servicing AS/400 and iSeries systems. What was fascinating as an outsider coming in to IBM was just how hard they clutched their pearls on the AS/400 system. I also serviced RS/6000 (pSeries) and RS/6000 SP clusters so I saw two different sides of the house operate. I was a typical pimply faced youth eager to learn, and the pSeries guys, both in the field and in IBM training schools were happy to feed me all the info I could digest. When I needed software for testing stuff on my own personal AIX box, stuff would get passed my way no questions asked. On the iSeries side, they would quite literally tell me "no" and shut the door in my face if I was asking too many questions. Despite the fact that OS400 can't be ran on any other hardware than IBM's, IBM guards the SLIC or OS "golden tapes" very jealously. The class for learning how to service iSeries was four weeks long back then, and our brains got crammed full of tons of information. But if I asked questions outside the scope of servicing the hardware I'd still get the door slammed in my face ("that's a different class kid, your manager will have to approve that"). I only worked there for about five years and I am grateful for the experience. I'm also glad I left when I did to avoid becoming "institutionalized" in my thinking as I had witnessed others had become. I have to assume that the pearl clutching came from IBM's experience with Amdahl and its prized mainframe (zSeries). They had become so afraid of competition that they were even afraid us lowly CE's would start freelancing and selling consulting services on the side on OS/400 work. As a result of that, you have a walled garden which is very hard for fresh talent to penetrate and IBM likes it fine that way. > — [dosman33 on hackernews](https://news.ycombinator.com/item?id=49145555) > We live in the shattered remains, badly reconstructed, of what a true operating system could be - we have some of the pieces (zfs, k8s, virtualization, scaling, failover, nixos, qubes) but imagine it all put together, orchestrated, carefully documented and tested by immense number of engineers. Ah, what could have been. > — [bombcar on hackernews · 3 comments](https://news.ycombinator.com/item?id=49143379) > The article was kind of terrible. If it had more emojis I would have said it was an AI generated summary. To really understand how strange AS/400 if you need to read Frank Soltis's book (he was the original architect of it at IBM). > — [rwmj on hackernews](https://news.ycombinator.com/item?id=49145367) > The problem is license costs. IBM makes a great system but almost all their customers have been working hard to replace it, not because of issues with the quality but the high license costs. > — [tmsbrg on hackernews · 2 comments](https://news.ycombinator.com/item?id=49143583) > Considering this article was 100% AI generated (according to Pangram), I doubt the author has much understand in of anything in the article. > — [trollbridge on hackernews](https://news.ycombinator.com/item?id=49145489) **Source threads** - [hackernews](https://news.ycombinator.com/item?id=49141937) · 39 points · 54 comments ## Similar posts on daily.dev - [IBM promises improved control of Db2 in hybrid environments](https://daily.dev/posts/ibm-promises-improved-control-of-db2-in-hybrid-environments-s9zcaadvq) · The Register · 0 upvotes · 0 comments - [Peek Into IBM’s System/360 With Vintage Training Film](https://daily.dev/posts/peek-into-ibm-s-system-360-with-vintage-training-film-oief6knzy) · Hackaday · 0 upvotes · 0 comments - [dBASE on the Kaypro II](https://daily.dev/posts/dbase-on-the-kaypro-ii-dwus9e9ru) · Two Stop Bits · 0 upvotes · 0 comments --- Tags: [#backend](https://daily.dev/tags/backend) [View this post on daily.dev](https://daily.dev/posts/400-the-database-operating-system-osadmins-nvrrsqalx) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"400) The Database Operating System – OSAdmins","url":"https://daily.dev/posts/400-the-database-operating-system-osadmins-nvrrsqalx","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/400-the-database-operating-system-osadmins-nvrrsqalx"},"datePublished":"2026-08-02T12:03:01.802Z","dateModified":"2026-08-02T16:14:05.137Z","description":"A deep-dive overview of IBM i (formerly AS/400, OS/400), exploring its unique architecture that integrates a relational database (Db2 for i) directly into the...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/5a74be644b462a9f3ef26e875d04d86f?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/5a74be644b462a9f3ef26e875d04d86f?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Hacker News","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Hacker News","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/hn","url":"https://daily.dev/sources/hn"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/400-the-database-operating-system-osadmins-nvrrsqalx","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"backend","timeRequired":"PT43M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Hacker News","item":"https://daily.dev/sources/hn"},{"@type":"ListItem","position":3,"name":"400) The Database Operating System – OSAdmins"}]} ```