The Random Ramblings of a Sysadmin

Recently, the company brought in a clownsultant (supposedly he'd not only taken a VCP but also been a VCP course instructor) to upgrade our VMWare ESX cluster to ESX 3.5 and VC 2.5. This lead to a number of interesting issues, that I'll list here - with solutions for your enjoyment:

1. Upgrade failed with the server stuck at GRUB after reboot
Solution: disconnect the fibers from the HBA before upgrading, they seem to confuse grub-install even if you select the right boot device (internal RAID) during install/upgrade.