ESX boot hangs on loading storage drivers

i have a ESX4 server，ESX boot Hangs onLoading storage-drivers，10minutes later  then continue booting normally

and when i shutdown/reboot ESX also hangs on

“please stand by while rebooting the system...

[1229.671924] Synchronizing SCSI cache for disk sdj :

[1229.67xxxx] Synchronizing SCSI cache for disk sdi :

[1229.671924] Synchronizing SCSI cache for disk sdh : "

so i reinstall the esx server, but the problem persists, and  i found that install/boot both Hangs onLoading storage-drivers 10minutes

i use DELL MD3000 storage, 2 controller, i found warning, then i switch all lun path to controller 0, but after some time all lun path auto switch use controller 1, others is OK

To make an earnest, thanks