I second the use of manually configuring additional isolation addresses. Using different subnets for management traffic within a cluster may introduce points of failure (think routing issues) with regards to HA. Please be certain that you really do need to use multiple subnets for management traffic within a cluster.
All the best,
Mike
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Mike Brown
VMware, Cisco Data Center, and NetApp dude
Consulting Engineer
Twitter: @VirtuallyMikeB
Blog: http://VirtuallyMikeBrown.com
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