Hi,
As I know, CentOS 6.x is not a supported OS on DL360 G5, HP Drivers page shows only CentOS 5 as compatible and with ProLiant Support Pack.
Also see this post on similar error.
According to this error, you may try updating the controller drivers or firmware or even ProLiant Support Pack if available for CentOS 6.x.
Thank You!
I am a HP employee.