[chef] how to install older ohai in omnibus chef install

[John Alberts < >]

It seems that ohai 6.14.0 which is included in the latest omnibus installer has a bug again with detecting Linux VServer guest ip's properly, so I need to use the ohai 0.6.12 or 0.6.8 release.  After a fresh omnibus chef install, how would I remove ohai 6.14.0 and install ohai 0.6.12?  I need to do it outside of Chef and get the ohai version changed before Chef run's for the first time, since ohai fails completley and Chef won't run at all.  Any ideas how to do this?

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John Alberts