AS/400 (IBM iSeries, AS/400e, eServer iSeries/400)

Contributor(s): Justin C. Haase, Jim Rothwell, Sue Huhn

The AS/400 - formally renamed the "IBM iSeries," but still commonly known as AS/400 - is a midrange server designed for small businesses and departments in large enterprises and now redesigned so that it will work well in distributed networks with Web applications. The AS/400 uses the PowerPC microprocessor with its reduced instruction set computer technology. Its operating system is called the OS/400. With multi-terabytes of disk storage and a Java virtual memory closely tied into the operating system, IBM hopes to make the AS/400 a kind of versatile all-purpose server that can replace PC servers and Web servers in the world's businesses, competing with both Wintel and UNIX servers, while giving its present enormous customer base an immediate leap into the Internet.

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The AS/400, one of IBM's greatest success stories, is widely installed in large enterprises at the department level, in small corporations, in government agencies, and in almost every industry segment. It succeeded another highly popular product, the System/36 and was itself based on a later, more sophisticated product, the System/38. AS/400 customers can choose from thousands of applications that have already been written and many have been "Web-enabled." IBM points to the AS/400's "uptime" of 99.9%.

The AS/400 comes with a database built-in. One widely-installed option is Domino (Notes with a Web browser).

According to IBM, these are some important new uses for the AS/400:

  • Data warehousing: With multi-gigabytes of RAM and multi-terabytes of hard disk space, the AS/400 can be a repository for large amounts of company data to which data mining could be applied.
  • Java application development: With its closely integrated Java virtual machine and new tools designed by IBM for building commercial applications with Java, the AS/400 can be used as a development system.
  • Web and e-commerce serving: Equipped with a Web server and applications designed to support e-commerce (taking orders, tracking orders, providing service to customers, working with partners and suppliers) and with firewall capabilities, the AS/400 can handle Internet serving for a moderate-size company.
  • Corporate groupware services: Assuming that Domino and Notes have been included with the system, it's designed to quickly provide a corporation with sophisticated e-mail, project file sharing, whiteboards, and electronic collaboration.
This was last updated in October 2008

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At end of my working life, I want to be beside AS/400.
Is AS/400 dead? Is it worth to look for a career in AS/400 as a fresher? Or its outdated? Please help with your views.
A good article for a beginner. But what can I say, AS/400 is still good for its purposes. It is a pity that their model lines are not being updated, although it does not prevent them from being a legend that is capable of anything even in 2017. And if you have old equipment and iSeries that you do not use, you can sell it, now many companies purchase equipment AS/400 for modernization and further sale.
What are the possible causes for disk failure in AS/400 servers?

Thank you in advance!!!
What does the "Adjustment Flag" prompt do in AS/400?

IBM released an easy to use computer series named as AS400 for small businesses and enterprises. These mid-range computer series delivered better performance and high data security as compared to other computer systems in the 80’s. 

The history of AS400 dates back to the year 1988. Before that, IBM had launched its System38 in 1979 along with a complete product line-System3, System32, System34, System36. Later, AS400 was launched with the OS OS400 which was able to move the programs written for System34 and System36 to AS400.

Read :  Everything to know about IBMi “AS400 / i-Series”