Hi, Toasters

We have one disk experiencing the following error:

Mon Apr 22 11:57:14 CES [ispfc_main:error]: Disk 0a.33: op 0x28:00ab0ae8:0008 sector 0 recovered error - (1 5d, 0) Mon Apr 22 11:57:14 CES [scsi.cmd.checkCondition:error]: Device 0a.33: Check Condition: CDB 0x28:00ab0ae8:0008: Sense Data recovered error - (0x1 - 0x5d 0x0 0x43).

Does anyone have any idea of what causes this error? Is it a harware error or just an error produced because a 'missmatch' in the data stored in the data and the parity disk? Usually, a media recovered error is reported by ontap as the following (usually, during disk scrub):

Sun Apr 14 01:24:11 CES [correonfs2: ispfc_main:error]: Disk 8a.18: op 0x28:01c67000:0080 sector 29782108 medium error - Unrecovered read error (3 11, 0) Sun Apr 14 01:24:11 CES [correonfs2: ispfc_main:notice]: Disk 8a.18: sector 29782108 will be reassigned Sun Apr 14 01:24:11 CES [correonfs2: ispfc_main:error]: Medium err for disk 8a.18 (serial no. 3EK0PAKS00007216RQAM). Sun Apr 14 01:24:11 CES [correonfs2: scsi.cmd.checkCondition:error]: Device 8a.18: Check Condition: CDB 0x28:01c67000:0080: Sense Data medium error - Unrecovered read error (0x3 - 0x11 0x0 0xe4). Sun Apr 14 01:24:11 CES [correonfs2: ispfc_main:error]: Disk 8a.18: op 0x28:01c67058:0008 sector 29782108 medium error - Unrecovered read error (3 11, 0) Sun Apr 14 01:24:11 CES [correonfs2: ispfc_main:notice]: Disk 8a.18: sector 29782108 will be reassigned Sun Apr 14 01:24:11 CES [correonfs2: ispfc_main:error]: Medium err for disk 8a.18 (serial no. 3EK0PAKS00007216RQAM). Sun Apr 14 01:24:11 CES [correonfs2: scsi.cmd.checkCondition:error]: Device 8a.18: Check Condition: CDB 0x28:01c67058:0008: Sense Data medium error - Unrecovered read error (0x3 - 0x11 0x0 0xe4). Sun Apr 14 01:24:11 CES [correonfs2: raid_stripe_owner:info]: read error from disk 8a.18 (S/N 3EK0PAKS00007216RQAM) block 3722763 Sun Apr 14 01:24:11 CES [correonfs2: raid_stripe_owner:notice]: Rewriting bad block from parity on disk 8a.18, block #3722763 Sun Apr 14 01:24:12 CES [correonfs2: ispfc_main:notice]: Disk 8a.18: sector 29782108 was reassigned

In the case below, it seems like sector 29782108 has been reassigned (by the internal hardware of the disk, I guess). In the first case (disk 0a.33), it has been recovered (I don't know how, it does not say anything about the parity disk).

What is a 'Sense Data error'? How is it produced?

Just willing to know a little more about how ontap manages its disks ...

Thanks in advantage. Kind Regards. _____________________________________________________

Oscar Rodríguez Hernández Dpto. HelpDesk de Sistemas email: orh@satec.es

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