Berkeley CSUA MOTD:Entry 11620
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2025/05/25 [General] UID:1000 Activity:popular
5/25    

2003/12/31-2004/1/1 [Computer/HW/Drives] UID:11620 Activity:nil
12/30   When copying a file from one IDE hard disk to another in one PC,
        what's to prevent a bit from getting flipped? are there hardware
        checksums?
        \_ yes, but....  Once you start copying gigs or TBs around the
           error rates are high enough that bad bits really happen.  The
           odds of this happening on your mp3 or porn collection are really
           slim and the odds that the altered bit actually changes a file
           in such a way that you notice is even slimmer but yes it can
           and does happen in the real world on PC quality hardware.
           \_ isn't there error-checking?  IDE drives are supposed to resend
              data when there's too much cross-talk, aren't they?
              \_ Get what you pay for, caveat emptor, and all those
                 other platitudes...
           \_ urlP
        \_ I don't know the answer, but you can do a file compare afterwards if
           there's a way to tell the OS to flush all file cache.
2025/05/25 [General] UID:1000 Activity:popular
5/25    

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2012/1/4-2/6 [Computer/HW/Drives] UID:54281 Activity:nil
1/4     I want to test how my servers behave during a disk failure and
        a RAID reconstruction so I want to simulate a hardware failure.
        How can I do this in Linux without having to physically pull
        a drive? These disks are behind a RAID card and run Linux. -ausman
        \_ According to the Linux RAID wiki, you might be able to use mdadm
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2011/9/14-10/25 [Computer/HW/Drives] UID:54173 Activity:nil
9/13    Thanks to Jordan, our disk server is no longer virtualized. Our long
        nightmare of poor IO performance should hopefully be over. Prepare for
        another long nightmare of poor hardware reliability!
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2011/2/14-4/20 [Computer/SW/Unix] UID:54039 Activity:nil
2/14    You sure soda isn't running windows in disguise?  It would explain the
        uptimes.
        \_ hardly, My winbox stays up longer.
        \_ Nobody cares about uptime anymore brother, that's what web2.0 has
           taught us.  Everything is "stateless".
           \_ You;d think gamers would care more about uptime.
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2010/7/22-8/9 [Computer/SW/OS/FreeBSD, Computer/HW/Drives] UID:53893 Activity:nil
7/22    Playing with dd if=/dev/random of=/dev/<disk> on linux and bsd:
        2 questions, on linux when <disk>==hda it always gives me this off
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2009/10/27-11/3 [Computer/HW/Drives] UID:53474 Activity:nil
10/27   I just read an article that Facebook had moved their database
        to all SSD to speed throughput, but now I can't find it. Has
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        \_ I hope you're not running mission critical data:
           http://ask.slashdot.org/story/09/10/27/1559248/Reliability-of-PC-Flash-SSDs?from=rss
        \_ Do you have any idea how much storage space is used by Facebook,
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2009/8/4-13 [Computer/SW/OS/Windows] UID:53239 Activity:kinda low
8/3     VMWare + Windows XP + Validation question. I need to test stuff with
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        actually *bought* a copy, please don't flame me for supporting evil
        M$). Is it possible to register the key once, and then duplicate it
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2009/7/28-8/6 [Computer/HW/Drives] UID:53216 Activity:nil
7/28    Does it make sense to defragment disks on VMWare? My 80GB disk
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2009/7/24-27 [Computer/SW/WWW/Browsers, Computer/SW/OS/OsX] UID:53191 Activity:kinda low
7/24    Firefox 3.5.1 on MacOS is a piece of crap. It crashes ALL THE TIME.
        It has crashed 3 or 4 times on me in the last hour, and not on
        the same pages either. The new Yahoo! home page also sucks ass.
        \_ os x keeps trashing my raid disk: '11 hours to rebuild. have fun
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2009/7/17-24 [Computer/SW/OS/OsX] UID:53156 Activity:kinda low
7/17    -rw-r--r--@
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        \_ The file has metadata attributes
           \_ How do I add/delete attributes to files? What about
              -rw-r--r--+ <-- what is the "+" sign? Also how do you make
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	...