AWS has long worked well with most of the major Linux vendors, but Microsoft "has a long history with Red Hat and Linux," IDC's Chen pointed out.
That history hasn't always been amicable. Not so very long ago, Microsoft CEO Steve Ballmer referred to Linux as a "cancer" in the technology world.
The resulting lack of support for RHEL was negatively affecting Microsoft's cloud business, Chen said. "It was a big hole."
More recently, current Microsoft CEO Satya Nadella has sung a very different tune.
Overall, the move underscores not just the competitiveness that currently dominates the cloud arena, Chen said, but also the recent transformation of Microsoft.
"If this doesn't show that this is a new Microsoft," Chen said, "I don't know what would."
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