There isn't any trouble getting Linux or Solaris running on a mainframe but there is a problem if you want to squeeze resellers for your OS.

Yeah - z/OS does have zlinux bundled in the standard suite. But then again, it runs over the z/VM. AFAIK, the problem is more in the software licensing part of the deal than the technical aspects of it.

A new environment for the mainframe would be welcome, as long as it doesn't come with icons, crashes and BSODs ;-)

"the problem is more in the software licensing part of the deal than the technical aspects of it."

Is that the same as a petty squabble over money, Paddy?

Oh no it doesn't. z/OS has its own 'Unix Branded' Unix Systems Services component that is an EBCDIC implementation of 'unix'.

IBM can't 'bundle' Linux with any of its operating system distributions. If any software distribution contains open source code then by implication the entire distribution falls under an Open Source agreement. And big blue is not about to turn z/OS or z/VM into 'open source'.

Linux for zSeries and System z is an ASCII implementation of Linux that runs on IBM zSeries and System z processors, either on the tin or as a z/VM guest system.

Software licencing is NOT an issue. You can download a copy of Linux from wherever you can get it for free on t'interweb, and IBM makes the patches to run it on zSeries / System z available so you can patch a kernel yourself if you want to. The patches represent about 2% of the total Linux code, and are in the area of mainframe device drivers - e.g. translate a raw Linux scsi disk I/O call into a zSeries ECKD disk I/O call, etc.

The pre-built and bundled 'Enterprise' Linux editions are packaged with support services. This is where the money changes hands. Linux is an Open Source operating system. You're not supposed to be able to sell it on or charge for it. What you are allowed to do is charge for any value add you bring to the bundle in terms of support etc.

For running vendor software, it is most often a cost saving. e.g. One vendor software licence for a System z CPU which can then run 20 Linuxes - versus - 20 vendor software licences for each of 20 single instances of Linux on 20 seperate Wintel/RISC boxes. No brainer.

Nige, no, that's not true. Refer to this text of the license (GPLv2 since we seem to be talking about Linux):

In addition, mere aggregation of another work not based on the Program with the Program (or with a work based on the Program) on a volume of a storage or distribution medium does not bring the other work under the scope of this License.

Is it Sun, trying to find any way to generate services revenue from Solaris because Solaris users are finding the alternatives so much more appealing, or is it IBM desperate to maintain it's services revenue from mainframes? I think this one's more a winner for the boys from Armonk. Sun helps IBM maintain one of the most lucrative and proprietary hardware goldmines going, whilst "opening" up it's own OS so other companies can undercut it with cheap "open" support. And at the same time makes it even easier for the Linux crowd to attack the installed z/OS base - "Hey, if IBM say we can run Slowaris on this, why don't we try Linux?"