diff options
Diffstat (limited to 'doc/sg_scan.8.linux')
-rw-r--r-- | doc/sg_scan.8.linux | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/doc/sg_scan.8.linux b/doc/sg_scan.8.linux new file mode 100644 index 00000000..06980004 --- /dev/null +++ b/doc/sg_scan.8.linux @@ -0,0 +1,78 @@ +.TH SG_SCAN "8" "May 2013" "sg3_utils\-1.36" SG3_UTILS +.SH NAME +sg_scan \- scans sg devices (or SCSI/ATAPI/ATA devices) and prints +results +.SH SYNOPSIS +.B sg_scan +[\fI\-a\fR] +[\fI\-i\fR] +[\fI\-n\fR] +[\fI\-w\fR] +[\fI\-x\fR] +[\fIDEVICE\fR]* +.SH DESCRIPTION +.\" Add any additional description here +.PP +If no \fIDEVICE\fR names are given, sg_scan does a scan of the sg +devices and outputs a line of information for each sg device that is +currently bound to a SCSI device. If one or more \fIDEVICE\fRs are given +only those devices are scanned. +Each device is opened with the O_NONBLOCK flag so that the scan will +not "hang" on any device that another process holds an O_EXCL lock on. +.PP +Any given \fIDEVICE\fR name is expected to comply +with (to some extent) the Storage Architecture Model (SAM see www.t10.org). +Any device names associated with the Linux SCSI subsystem (e.g. /dev/sda +and /dev/st0m) are suitable. Devices names associated with ATAPI +devices (e.g. most CD/DVD drives and ATAPI tape drives) are also suitable. +If the device does not fall into the above categories then an ATA +IDENTIFY command is tried. +.PP +In Linux 2.6 and 3 series kernels, the lsscsi utility may be helpful. Apart +from providing more information (by data\-mining in the sysfs pseudo file +system), it does not need root permissions to execute, as this utility +would typically need. +.SH OPTIONS +.TP +\fB\-a\fR +do alphabetical scan (i.e. sga, sgb, sgc). Note that sg device nodes with +an alphabetical index have been deprecated since the Linux kernel 2.2 +series. +.TP +\fB\-i\fR +do a SCSI INQUIRY, output results in a second (indented) line. If the device +is an ATA disk then output information from an ATA IDENTIFY command +.TP +\fB\-n\fR +do numeric scan (i.e. sg0, sg1...) [default] +.TP +\fB\-w\fR +use a read/write flag when opening sg device (default is read\-only) +.TP +\fB\-x\fR +extra information output about queueing +.SH NOTES +This utility was written at a time when hotplugging of SCSI devices +was not supported in Linux. It used a simple algorithm to scan sg +device nodes in ascending numeric or alphabetical order, stopping +after there were 4 consecutive errors. +.PP +In the Linux kernel 2.6 series, this utility uses sysfs to find which +sg device nodes are active and only checks those. Hence there can be +large "holes" in the numbering of sg device nodes (e.g. after an +adapter has been removed) and still all active sg device nodes will +be listed. This utility assumes that sg device nodes are named using +the normal conventions and searches from /dev/sg0 to /dev/sg4095 +inclusive. +.SH EXIT STATUS +The exit status of sg_scan is 0 when it is successful. Otherwise see +the sg3_utils(8) man page. +.SH AUTHORS +Written by D. Gilbert and F. Jansen +.SH COPYRIGHT +Copyright \(co 1999\-2013 Douglas Gilbert +.br +This software is distributed under the GPL version 2. There is NO +warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. +.SH "SEE ALSO" +.B lsscsi(8) |