244 lines
4.9 KiB
HTML
244 lines
4.9 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
|
|
<HTML
|
|
><HEAD
|
|
><TITLE
|
|
>Device Names in scsidev</TITLE
|
|
><META
|
|
NAME="GENERATOR"
|
|
CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
|
|
REL="HOME"
|
|
TITLE="The Linux 2.4 SCSI subsystem HOWTO"
|
|
HREF="index.html"><LINK
|
|
REL="UP"
|
|
TITLE="Names and Addresses"
|
|
HREF="names.html"><LINK
|
|
REL="PREVIOUS"
|
|
TITLE="Device Names in devfs"
|
|
HREF="dnamesdevfs.html"><LINK
|
|
REL="NEXT"
|
|
TITLE="Kernel Configuration"
|
|
HREF="kconfig.html"></HEAD
|
|
><BODY
|
|
CLASS="sect1"
|
|
BGCOLOR="#FFFFFF"
|
|
TEXT="#000000"
|
|
LINK="#0000FF"
|
|
VLINK="#840084"
|
|
ALINK="#0000FF"
|
|
><DIV
|
|
CLASS="NAVHEADER"
|
|
><TABLE
|
|
SUMMARY="Header navigation table"
|
|
WIDTH="100%"
|
|
BORDER="0"
|
|
CELLPADDING="0"
|
|
CELLSPACING="0"
|
|
><TR
|
|
><TH
|
|
COLSPAN="3"
|
|
ALIGN="center"
|
|
>The Linux 2.4 SCSI subsystem HOWTO</TH
|
|
></TR
|
|
><TR
|
|
><TD
|
|
WIDTH="10%"
|
|
ALIGN="left"
|
|
VALIGN="bottom"
|
|
><A
|
|
HREF="dnamesdevfs.html"
|
|
ACCESSKEY="P"
|
|
>Prev</A
|
|
></TD
|
|
><TD
|
|
WIDTH="80%"
|
|
ALIGN="center"
|
|
VALIGN="bottom"
|
|
>Chapter 3. Names and Addresses</TD
|
|
><TD
|
|
WIDTH="10%"
|
|
ALIGN="right"
|
|
VALIGN="bottom"
|
|
><A
|
|
HREF="kconfig.html"
|
|
ACCESSKEY="N"
|
|
>Next</A
|
|
></TD
|
|
></TR
|
|
></TABLE
|
|
><HR
|
|
ALIGN="LEFT"
|
|
WIDTH="100%"></DIV
|
|
><DIV
|
|
CLASS="sect1"
|
|
><H1
|
|
CLASS="sect1"
|
|
><A
|
|
NAME="dnamesscsidev"
|
|
></A
|
|
>3.4. Device Names in scsidev</H1
|
|
><P
|
|
> A utility program called <B
|
|
CLASS="command"
|
|
>scsidev</B
|
|
> adds device names to
|
|
the <TT
|
|
CLASS="filename"
|
|
>/dev/scsi</TT
|
|
> directory that reflect the SCSI address
|
|
of each device. The first 2 letters of the name are the upper level SCSI
|
|
driver name (i.e. either sd, sr, st or sg). The number following the "h"
|
|
is the host number while the number following the "-" is meant for
|
|
host identification purposes. For PCI adapters this seems to be always
|
|
0 while for ISA adapters it is their IO address. [Perhaps this field
|
|
could be made more informative or dropped.] The numbers following
|
|
the "c", "i" and "l" are channel (bus), target id and lun values
|
|
respectively. Raw disks are shown without a trailing partition number
|
|
while partitions contained within them are shown with the partition
|
|
number following a "p".
|
|
</P
|
|
><P
|
|
> The <B
|
|
CLASS="command"
|
|
>scsidev</B
|
|
> would typically be run as part of the
|
|
boot up sequence. It may also be useful to run it after the SCSI
|
|
configuration has changed (e.g. adding or removing lower level driver
|
|
modules, or the use of the add/remove-single-device command). After
|
|
<B
|
|
CLASS="command"
|
|
>scsidev</B
|
|
> has been run on my system which contains
|
|
2 disks, a cd reader and writer plus a scanner, then the following
|
|
names were added in the <TT
|
|
CLASS="filename"
|
|
>/dev/scsi</TT
|
|
> directory:
|
|
<TABLE
|
|
BORDER="0"
|
|
BGCOLOR="#E0E0E0"
|
|
WIDTH="100%"
|
|
><TR
|
|
><TD
|
|
><FONT
|
|
COLOR="#000000"
|
|
><PRE
|
|
CLASS="programlisting"
|
|
> $ ls -l /dev/scsi/ # abridged
|
|
total 0
|
|
brw------- 8, 0 Sep 2 11:56 sdh0-0c0i0l0
|
|
brw------- 8, 1 Sep 2 11:56 sdh0-0c0i0l0p1
|
|
...
|
|
brw------- 8, 8 Sep 2 11:56 sdh0-0c0i0l0p8
|
|
brw------- 8, 16 Sep 2 11:56 sdh0-0c0i1l0
|
|
brw------- 8, 17 Sep 2 11:56 sdh0-0c0i1l0p1
|
|
...
|
|
brw------- 8, 24 Sep 2 11:56 sdh0-0c0i1l0p8
|
|
crw------- 21, 0 Sep 2 11:56 sgh0-0c0i0l0
|
|
crw------- 21, 1 Sep 2 11:56 sgh0-0c0i1l0
|
|
crw------- 21, 2 Sep 2 11:56 sgh1-0c0i2l0
|
|
crw------- 21, 3 Sep 2 11:56 sgh1-0c0i5l0
|
|
crw------- 21, 4 Sep 2 11:56 sgh1-0c0i6l0
|
|
br-------- 11, 0 Sep 2 11:56 srh1-0c0i2l0
|
|
br-------- 11, 1 Sep 2 11:56 srh1-0c0i6l0
|
|
</PRE
|
|
></FONT
|
|
></TD
|
|
></TR
|
|
></TABLE
|
|
>
|
|
The mapping between the SCSI generic device names (sg) and their corresponding
|
|
names when controlled by other upper level drivers (i.e. sd, sr or st) can
|
|
be seen by looking for name matches when the second letter is ignored.
|
|
Hence "sdh0-0c0i0l0" and "sgh0-0c0i0l0" refer to the same device. By process
|
|
of elimination the "sgh1-0c0i5l0" filename is the scanner since that class
|
|
of devices can only be accessed via the sg interface.
|
|
</P
|
|
><P
|
|
> The scsidev package also includes the ability to introduce names like
|
|
<TT
|
|
CLASS="filename"
|
|
>/dev/scsi/scanner</TT
|
|
> by manipulating the <TT
|
|
CLASS="filename"
|
|
> /etc/scsi.alias</TT
|
|
> configuration file. The package also includes
|
|
the useful <B
|
|
CLASS="command"
|
|
>rescan-scsi-bus.sh</B
|
|
> utility.
|
|
For further information about <B
|
|
CLASS="command"
|
|
>scsidev</B
|
|
> see
|
|
<A
|
|
HREF="refs.html#W6"
|
|
>W6</A
|
|
>. On my system, both devfs and scsidev
|
|
co-exist happily.
|
|
</P
|
|
></DIV
|
|
><DIV
|
|
CLASS="NAVFOOTER"
|
|
><HR
|
|
ALIGN="LEFT"
|
|
WIDTH="100%"><TABLE
|
|
SUMMARY="Footer navigation table"
|
|
WIDTH="100%"
|
|
BORDER="0"
|
|
CELLPADDING="0"
|
|
CELLSPACING="0"
|
|
><TR
|
|
><TD
|
|
WIDTH="33%"
|
|
ALIGN="left"
|
|
VALIGN="top"
|
|
><A
|
|
HREF="dnamesdevfs.html"
|
|
ACCESSKEY="P"
|
|
>Prev</A
|
|
></TD
|
|
><TD
|
|
WIDTH="34%"
|
|
ALIGN="center"
|
|
VALIGN="top"
|
|
><A
|
|
HREF="index.html"
|
|
ACCESSKEY="H"
|
|
>Home</A
|
|
></TD
|
|
><TD
|
|
WIDTH="33%"
|
|
ALIGN="right"
|
|
VALIGN="top"
|
|
><A
|
|
HREF="kconfig.html"
|
|
ACCESSKEY="N"
|
|
>Next</A
|
|
></TD
|
|
></TR
|
|
><TR
|
|
><TD
|
|
WIDTH="33%"
|
|
ALIGN="left"
|
|
VALIGN="top"
|
|
>Device Names in devfs</TD
|
|
><TD
|
|
WIDTH="34%"
|
|
ALIGN="center"
|
|
VALIGN="top"
|
|
><A
|
|
HREF="names.html"
|
|
ACCESSKEY="U"
|
|
>Up</A
|
|
></TD
|
|
><TD
|
|
WIDTH="33%"
|
|
ALIGN="right"
|
|
VALIGN="top"
|
|
>Kernel Configuration</TD
|
|
></TR
|
|
></TABLE
|
|
></DIV
|
|
></BODY
|
|
></HTML
|
|
> |