Ahhh...same issue..
From the workarounds:
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This is a known issue with ESXi 5.5 Update 1.
Currently, there is no resolution.
To work around this issue, use one of these methods:
- Contact HP support and request an updated HP Custom Image for ESXi 5.5 Update 1.
- Upgrade the host using the HP 5.5 Update 1 March 2014 image and then apply latest patches.
- Build a custom ISO with HP 5.5 Update 1 June 2014. Remove the Broadcom NX2 packages and replace with the older version from the HP 5.5 GA build available here. Use this modified image to upgrade the hosts.
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Did anyone tried to upgrade via VUM from 5.1 to 5.5u1 with the March 2014 HP Image? I would like to try that...but cant find the March 2014 on the HP page Customize VMware ESXi Images for HP ProLiant Servers...grrr