Messages in this thread | | | Date | Sat, 19 Apr 2003 19:41:20 +0100 | From | "Dr. David Alan Gilbert" <> | Subject | Re: Are linux-fs's drive-fault-tolerant by concept? |
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Hi, Besides the problem that most drive manufacturers now seem to use cheese as the data storage surface, I think there are some other problems:
1) I don't trust drive firmware. 2) I don't think all drives are set to remap sectors by default. 3) I don't believe that all drivers recover neatly from a drive error. 4) It is OK saying return the drive and get a new one - but many of us can't do this in a commercial environment where the contents of the drive are confidential - leading to stacks of dead drives (often many inside their now short warranty periods).
To be fair I'm not sure if it is only the drive firmware I don't trust - it could be the controllers and the IDE drivers as well - I don't know.
While RAID works well for drives that just go pop and die, for drives with dodgy firmware we just sit there and watch the filesystems decay. I don't think the kernel can do much about that - but it is a sad state.
I'd find two things useful in this respect: 1) A tool to check the consistency of a RAID - presuming I shut my RAID down safely I should actually be able to use the redundant information to test it; this should reveal corruption early. (Perhaps the kernel could check a few sectors a second in the background)
2) A disc exerciser - something that I can use to see if this drive, connected to this controller, on this motherboard on this kernel actually works and keeps its data safe before I put it into live service.
Dave (After a few weeks of fighting pissy IDE hard drives)
---------------- Have a happy GNU millennium! ---------------------- / Dr. David Alan Gilbert | Running GNU/Linux on Alpha,68K| Happy \ \ gro.gilbert @ treblig.org | MIPS,x86,ARM,SPARC,PPC & HPPA | In Hex / \ _________________________|_____ http://www.treblig.org |_______/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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