The iSeries is the only IBM server platform not to be refreshed since the eServer branding was introduced last October. As a result, users will be keen to see whether the company has addressed two obvious weaknesses: the inability to support Linux and the primitive support for storage area networks (San).
IBM promised a year ago that Linux support would come to the iSeries, as it has to all its other servers, but the company has added nothing to that statement since. Ray Titcombe, chairman of the IBM Computer Users Association and an AS/400 user, said, "They are falling very short of the mark in terms of taking up Linux."
So far, IBM has said only that the iSeries will support the Linux kernel in a secondary logical partition on selected models. Presumably that means the more powerful 800 series models, or their replacements.
The decision to run Linux in a partition is interesting as it is a different approach from the way IBM supports Windows NT/2000 on the iSeries. This is achieved by installing a separate processor which runs NT co-operatively with OS/400 within the box. This plug-in card has been known by a variety of names - until recently the Integrated Netfinity Server - but, following the launch last week of the 850MHz version, is now called the Integrated xSeries Server.
This form of NT support has proved popular, with one in five iSeries models being shipped with at least one plug-in card, up to a maximum of 16.
IBM has been promoting the range as an ideal vehicle for NT file and print server consolidation. As Linux servers are increasingly being used for these relatively simple applications, it makes sense for IBM to make the same push. An iSeries server can have up to 24 partitions, one per processor.
Independent analyst Phil Payne said he is not convinced that IBM will announce Linux for iSeries in the March launch. But Titcombe believes it will definitely harm the credibility of the iSeries if IBM does not announce Linux support soon. "In the longer term, it will definitely put the box at a disadvantage," he said.
With Sans, IBM has good reason either to introduce support now, or to delay doing so indefinitely. There are factions in IBM fighting both corners and it is not clear whether the pro-San lobby will win.
Currently, an AS/400 or iSeries can only be attached to a San using a SCSI adaptor, which offers a prehistoric level of performance and limits the distance between the server and the San storage to a maximum of 25m. This is a consequence of IBM's decision in the mid-1990s to move disc storage under the covers. The stated reason was to improve performance; the effect was to kill off the plug-compatible competition.
As Titcombe put it, "If it makes the AS/400 open-ended, a lot of other suppliers' products will go into those accounts. It doesn't have to be much - anything less than 100% means IBM is losing out. So, while acknowledging that users are pressing IBM to introduce San support, I don't think that will happen now."
Payne agreed, and added that IBM's San strategy is being driven by its software subsidiary Tivoli which is weak on AS/400. "I'd wait for a Tivoli commitment to the platform before expecting anything," he said.
Tony Lock, senior analyst at Bloor Research, takes the opposite view, "I would not expect IBM to try to hold back the tide," he said.
He pointed out that IBM has been concentrating on adding features such as capacity upgrade on demand and probably wants these capabilities to be available on all platforms, including the iSeries. "I would expect them to do anything they can to enhance their capabilities in the storage area," he said.
This was first published in February 2001