[CentOS] kernel errors

For monday this week I began to receive these advice by email from the server; Wht's the meaning?

Disk read problem or else?

--------------------- Kernel Begin ------------------------

WARNING: Kernel Errors Present I/O error: dev 08:02, sect...: 4Time(s) Additional sense indicates Unrecovered read error...: 4Time(s) Info fld=0x4f9c9, Current sd08:02: sense key Medium Error...: 1Time(s) Info fld=0x50e37, Current sd08:02: sense key Medium Error...: 1Time(s) Info fld=0x517a1, Current sd08:02: sense key Medium Error...: 1Time(s) Info fld=0x517e2, Current sd08:02: sense key Medium Error...: 1Time(s) ------------------------------------------------------------------------------------------

--- Michel Donais