Two days ago RyanWI posted about an unidentified partition which generates errors in the vmkernel log. Today I visited a customer with the same setup, Dell servers and an EMC SAN and I was curious if I could reproduce this error. Well I did not had not much trouble reproducing the error because they already had the same issue. I encountered the following errors in the vmkernel log:

Feb 12 09:16:47 esx1 kernel: SCSI device sdc: 2097151 512-byte hdwr sectors (1074 MB)
Feb 12 09:16:47 esx1 kernel: sdc: I/O error: dev 08:20, sector 0
Feb 12 09:16:47 esx1 kernel: I/O error: dev 08:20, sector 0
Feb 12 09:16:47 esx1 kernel: unable to read partition table

After a close inspection it seems that in the DRAC Bios of the Dell server the “Virtual Media Configuration, Virtual Media” is set to “attached”, this causes a unrecognizable device to appear which causes the above errors. If you set the “Virtual Media” to “detached” the problem is solved.