FreeBSD Manual Pages
SG_PREVENT(8) SG3_UTILS SG_PREVENT(8) NAME sg_prevent - send SCSI PREVENT ALLOW MEDIUM REMOVAL command SYNOPSIS sg_prevent [--allow] [--help] [--prevent=PC] [--verbose] [--version] DEVICE DESCRIPTION Sends a SCSI PREVENT ALLOW MEDIUM REMOVAL command to DEVICE. The de- fault action of this utility is to prevent the removing or ejecting of the medium from a drive. This is done by ignoring the SCSI START STOP UNIT command (see sg_start) and ignoring the eject button on the drive when the user presses it. Drives that hold removable disks, tape car- tridges or cd/dvd media typically implement this command. The defini- tion of the "prevent" codes for this command differ between disks and tapes (covered by SBC-3 and SSC-3) and cd/dvd drives (covered by MMC-5). The "prevent codes" described here are from MMC-5. OPTIONS Arguments to long options are mandatory for short options as well. -a, --allow allow medium removal. This is equivalent to setting to '--pre- vent=2'. Cannot be used with --prevent=PC option (i.e. either use no options (hence prevent removal), this option or --pre- vent=PC). -h, --help output the usage message then exit. -p, --prevent=PC where PC is a prevent code value. Defined values are: 0 allows removal, 1 prevents removal (default), 2 allows persistent re- moval while 3 prevents persistent removal. "Persistent" in this context means that the initiator (port) that successfully uses code 3 blocks other initiators (ports) from allowing removal. A "persistent prevent" state can be cleared by the owner allowing persistent removal (code 2) or a power cycle (or anything that resets the device (LU)) or some special commands (e.g. various service actions of Persistent Reserve Out, see SPC-3). -v, --verbose increase the level of verbosity, (i.e. debug output). -V, --version print the version string and then exit. EXIT STATUS The exit status of sg_prevent is 0 when it is successful. Otherwise see the sg3_utils(8) man page. AUTHORS Written by Douglas Gilbert. REPORTING BUGS Report bugs to <dgilbert at interlog dot com>. COPYRIGHT Copyright (C) 2004-2012 Douglas Gilbert This software is distributed under a BSD-2-Clause license. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR- POSE. SEE ALSO sg_start(sg3_utils), sg_persist(sg3_utils) sg3_utils-1.35 November 2012 SG_PREVENT(8)
NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT STATUS | AUTHORS | REPORTING BUGS | COPYRIGHT | SEE ALSO
Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=sg_prevent&sektion=8&manpath=FreeBSD+Ports+14.3.quarterly>