Al Hopper wrote: > On Thu, 29 Nov 2007, Ross wrote: > > .... reformatted ... > >> Might be off-topic slightly, but why not raid-z2? We're looking at >> a thumper ourselves and I'd be nervous of data loss with single >> parity raid (I've had enough close calls with SCSI drives, let alone >> SATA). >> > > What do you mean by "let alone SATA"? > > One of the *big* issues with (parallel bus) SCSI, is, and always has > been, that a single "problem" SCSI device, could mess up the SCSI bus > and cause all kinds of nasty, system level, errors. And then there's > the old saying: "all SCSI issues are (caused by SCSI) bus termination > issues". All this aside from the issues with routing/supporting heavy > 68-wire external SCSI cables and connectors. > > I've personally (and professionally) been bitten by all 3 above > scenarios - more than once! IMHO, SATA point-to-point serial links > are far more reliable than anything I could build with SCSI > technology. > > Thank goodness for SATA and SAS.... >
pick your failure modes :-) I've got lots of scars from the first 8 years of SCSI... async vs sync, DB-50s, tagged queuing firmware bugs, terminators, simple parity protection, etc. Today many of these are more-or-less solved, but we do see RFI with the SATA/SAS interconnect and firmware will always have bugs. End-to-end error detection is a good thing. -- richard _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
