Content-type: text/html Man page of scu


Section: Maintenance Commands (8)
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scu - SCSI CAM Utility Program  


/sbin/scu [ -options... ] [ command [ keywords... ]]  


The SCSI utility program, scu, interfaces with the CAM I/O subsystem and the peripherals attached to the SCSI buses. Use this program to maintain and diagnose problems with SCSI peripherals and the CAM I/O subsystem.

The scu utility program has an extensive help feature. Log in as root and enter /sbin/scu help at the command prompt to view the help overview and enter a ? at the topic> prompt to view a list of the utility's commands and conventions.

The file /sbin/scu.hlp contains the help information used in the help feature.  


Specifies the user agent path. Specify the raw device pathname. You must specify a character device special file, for example, /dev/rrz3c.

If the device name is not specified on the command line, the program checks the environment variable SCU_DEVICE to define the device name. Do not execute a startup script. Enable pipe operation mode. Specify a script startup file name.  


The following table summarizes the scu commands and their functions. Refer to the help command for complete syntax and examples of use.


allowAllows media removal from a device
changeChanges mode pages for a device
downloadDownloads microcode to a device
dumpDumps data from a device
ejectStops a CD-ROM and then ejects its caddy
erasePerforms erase operations on a device
exit Exit the scu program. Ctrl/d can be used in interactive operation. An alias for exit is quit.
evaluateEvaluates an expression
formatFormats disk media
helpDisplays help on scu command elements
mbadProduces hard and soft errors on disks
mtIssues one of the supported magnetic tape commands
onerrorControls program actions when an error occurs
pausePauses playing a CD-ROM audio disk
playPlays tracks on a CD-ROM audio disk
preventPrevents removal of media from a device
readPerforms read operations on a device
reassignReassigns a defective block on a disk device
releaseReleases a reserved device or a frozen SIM queue
repeatDefines a repeat count for a series of commands
reserveReserves a device for exclusive use
resumeResumes playing a paused CD-ROM audio disk
resetResets a bus or device
rezeroIssues a CAM Bus Reset CCB command
scan Scans device media or the CAM Equipment Device Table (EDT)
seekSeeks a logical block address
set Sets parameters for a device or the scu program
shellExits to shell program until you exit the shell
show Displays parameters for a device or the scu program
sleep Specifies the time the scu program is to sleep
sourceSources input from an external command file
startStarts a unit that is stopped
stopStops a unit
switchSwitches to another device
systemPasses one system command to the shell program
testPerforms tests on a controller
timeTimes command sequences
turIssues a Test Unit Ready command to a device
usleep Specifies the time the scu program is to sleep (in microseconds).
verifyPerforms verify operations on a device
writePerforms write operations on a device
xzaPerforms operations on the KZMSA controller
zeroZeros device or scu program parameters



Commands that modify device data or device parameters require write access to the device entry. Applications that change the volume level of the CDROM must open the device for write access since a SCSI Mode Select command is used to modify the volume level.  


To format an RX26 diskette at extra density, enter: scu> format density ED

To verify 1024 blocks starting at block 1000, enter: scu> verify media starting 1000 length 1024

To display all changeable mode pages for a device, enter: scu> show page pcf changeable

To display inquiry information for all devices on the first SCSI bus at lun 0 in the Equipment Device Table (EDT), enter: scu> show edt bus 0 lun 0 full  


For all commands, scu runs and exits with 0 for success, 1 for warning, or -1 for failure status.  


When a SCSI device error occurs, both the sense key and the addition sense code or qualifier are decoded and displayed as follows: scu: Sense Key = 0x5 = ILLEGAL REQUEST - Illegal request or CDB parameter,
     Sense Code/Qualifier = (0x20, 0) = Invalid command operation code

This error indicates that you have issued a command that is not supported by the selected device. This can happen for optional commands that are not supported by all devices.  


The SCSI Utility executable file. The device entry for the CAM User Agent driver. Contains the scu help information.  


Commands: file(1), more(1).

Functions: open(2), close(2), ioctl(2), fopen(3), fgets(3), fputs(3), popen(3), pclose(3), malloc(3), printf(3), fprintf(3).

American National Standard for Information Systems, Small Computer Systems Interface - 2 (SCSI - 2), X3.131-199X

American National Standard for Information Systems, SCSI-2 Common Access Method: Transport and SCSI Interface Module, working draft, X3T9.2/90-186 delim off




This document was created by man2html, using the manual pages.
Time: 02:40:27 GMT, October 02, 2010