[lkml]   [2001]   [Jan]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: Linux not adhering to BIOS Drive boot order?
    "J . A . Magallon" wrote:

    > Average users you are targetting with that automagical
    > card detection even do not know there are SCSI and IDE disks. They just
    > want a 30Gb ide disk to install linux and play. If they involve with SCSI
    > and ID numbers and multiple cards and so on they can read some docs and
    > rebuild a kernel.

    Like Michael Meissner, I have been using Unix-like systems
    since it first came to Japan around 1981 : the first one was
    on a VAX at a university computer centre. (Its official English
    name was spelled with centre.)

    I came to use Linux after I bought Yggdrasil Fall 1994 disk.
    I began using it regularly for the last two or three years
    (after OS/2).

    Anyway, I view myself a typical Linux end-user in
    the framework of linux system hacker, linux
    tools developer and the rest (user).
    All I do on my PC is run netscape, read e-mails,
    post news articles, run editor to edit documents,
    and compile a few utilities and such (for
    using openssh).

    And maybe I occasionally produce patches when I notice
    a few problems in these utilities and send them
    to the original writers or the current maintainers.
    (The average users that J.A. Magallon have in mind
    may not produce patches, but I am not sure.)

    Granted I probably have more general knowledge of computers,
    (administered and used Data General MV [:-)], DEC, HP, Sun, ...]
    than average users,
    but then I was totally confused about the
    recognition order of SCSI devices under Linux when I
    had the second SCSI adaptor in my PC.
    As a matter of fact, I hit on a dormant bug/feature
    in the SCSI subsystem and was helpless until
    I wrote to Kurt Garloff(DC390(tmscsim) maintainer).

    There was not much documentation to rely on then.
    Is there enough, today? I wonder.

    It is true that with 2.4.x kernel:
    - we can control the recognition order of different
    brand of SCSI cards using scsihosts kernel parameter.
    (Don't know if this works under non-x86 platforms.)
    I use loadlin and scsihosts does work.

    - we can possibly control the recognition order of
    the same brand of cards either by
    - the driver (module) parameter if the driver supports
    it, or
    - by swapping the bus slots of the drivers (sometimes),
    - or probably swapping the cable if all the devices
    are external to the box (if appropriate).
    These might be documented somewhere, but I am not sure.
    Maybe the config script or rather the short help message
    that appears might want to mention this somewhere.

    Then there is the naming scheme:

    As noted recently, the name of the devices
    shift if we add, say, a disk in the SCSI chain.

    By going to `devfs', I am told that the naming becomes
    consistent, but unfortunately, I have not
    yet figured out how to write the initializing devfs
    script for my Debian GNU/Linux system yet.
    (Yes, I went to R. Gooch home page and started to
    read the howto doc there, but I am not entire sure of
    the way initializing script under /etc/rc" ought to be
    written for my Debian GNU/Linux : rather than risking
    my system's health, I have given up and hoping that
    Debian distribution will have devfs as part of standard
    installation soon.)

    Anyway, from the viewpoint of Linux (end) users,

    - there is not much in the way of documentation.
    I wonder if the SCSI-HOWTO is ever updated these days.

    - Read the source also doesn't work very well
    even if the user does read C source code with
    15+ years of C programming (from my own experience)
    SCSI subsystem is rather hard to read.
    It is a good thing that Alan Cox did the
    major surgery of re-formatting the code
    during 2.3.xx development.

    My point is that SCSI subsystem under Linux is
    not very user-friendly as of now.

    I have to wonder then what subsystems of Linux is
    user-friendlier than SCSI subsystem. I don't know.
    I have configured network card, Intel EEPRO/100 under linux,
    and didn't have much trouble, but then
    I have configured network at the office many many times, and
    so it helped me, I guess.

    In comparison, the problem with Linux SCSI subsystem is that
    I have configured SCSI disks, tape drives, etc. at the office
    many times, but the experience didn't carry over very well.
    That is it.

    I can't pin point what (mis-)features of linux make it difficult
    for me to share the past SCSI experience:
    Maybe the devfs thing would help if only it has
    better introduction documents somewhere.

    It could be that this is the fate of open source system where the
    device drivers are written by totally independent groups
    with various features creeping/implemented at different
    speeds in different drivers. If this is the case, then
    there is no intrinsic cure.

    Anyway, better documentation would help to certain extent certainly.
    The paragraph between " ......" above can be
    ripped and inserted with more detailed explanation of
    scsihosts in such a document.

    Anyway, viewing the (end) users as dumb who just want to play
    puts me in a very uncomfortable position.
    I guess (hope) I am not that dumb at all, and yet
    for heaven's sake, I could not get my two SCSI cards
    working for a few weeks (due to a bug), and I had
    read the docs many times during the time.

    There will be more users like Michael Meissner and me
    who have past experience with other systems before
    and yet a NEWBIE linux users initially: There will be
    more such users since Linux seems to get more management
    nods in the future.

    And these experienced NEWBIESs probably
    can't figure out these SCSI problems under linux either and
    I frankly doubt if the old SCSI-HOWTO docs might help.
    (I checked a few web pages : was the current
    how-to re-written in 1996?)

    Something needs to be done here.

    PS: I have now about 5 or 6 SCSI host adaptors in
    a few PC boxes.
    I hate IDE/ATA disks with all the geometry problems.
    Also, being able to use external drives help cool down
    the PC boxes IMHO.

    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to
    Please read the FAQ at

     \ /
      Last update: 2005-03-22 13:22    [W:0.030 / U:6.832 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site