We've got a bunch of SATA Seagate Barracuda ES drives, namely, ST3250620NS -- "enterprize" class. And now I wonder what's wrong with - either those drives, or sdparm, or kernel. In particular, sdparm can't change WCE bit, like this: # sdparm --clear=WCE -v -v /dev/sda mp_settings: page,subpage=0x8,0x0 num=1 pdt=0 start_byte=0x2 start_bit=2 num_bits=1 val=0 acronym: WCE inquiry cdb: 12 00 00 00 24 00 /dev/sda: ATA ST3250620NS 3.AE mode sense (10) cdb: 5a 00 08 00 00 00 00 00 04 00 mode sense (10) cdb: 5a 00 08 00 00 00 00 00 24 00 mode select (10) cdb: 55 10 00 00 00 00 00 00 24 00 mode select (10) parameter block 00 00 00 00 00 00 00 08 00 00 00 00 00 00 02 00 08 12 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 mode select (10): Fixed format, current; Sense key: Illegal Request Additional sense: Invalid field in cdb Raw sense data (in hex): 70 00 05 00 00 00 00 0a 00 00 00 00 24 00 00 00 00 00 change_mode_page: failed setting page: Caching (SBC) # _ We also have several "desktop" drives similar to the ones above -- ST3250620AS. And with those, I can change settings, unlike with the NS series: # sdparm --clear=WCE /dev/sda /dev/sda: ATA ST3250620AS J # _ What I also observed is that `sdparm -a' output is a bit different for the two. For the NS series, it looks like this: Caching (SBC) mode page: WCE 1 ... While for the AS series, it is like: Caching (SBC) mode page: WCE 1 [cha: y] ... The difference is that for the AS drives, sdparm displays whenever the parameter is changeable, while for the NS ("enterprise") disk, it does not. So I wonder -- is it the drive which is bad, or something's wrong with sdparm? To me, it should work the opposite way (IF there should be any difference at all) -- i.e., I can understand when for a "desktop" (consumer) drive I can't change some settings, while for "enterprise" class drive I have more control. Any ideas? Should I RMA those drives and/or replace them with the AS ones? :) Thanks. /mjt - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html