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geom(8) [freebsd man page]

GEOM(8) 						    BSD System Manager's Manual 						   GEOM(8)

NAME
geom -- universal control utility for GEOM classes SYNOPSIS
geom class help geom class list [-a] [name ...] geom class status [-ags] [name ...] geom class load [-v] geom class unload [-v] DESCRIPTION
The geom utility is used to control various GEOM classes. A class has to be aware of geom(8) communication methods, but there are also some standard commands which can be used for existing geom(8) unaware classes. Here is the list of standard commands: help List all available commands for the given class. list Print detailed information (within the given class) about all geoms (if no additional arguments were specified) or the given geoms. This command is only available if the given class exists in the kernel. Additional options include: -a Print information for geoms without providers. status Print general information (within the given class) about all geoms (if no additional arguments were specified) or the given geoms. This command is only available if the given class exists in the kernel. Additional options include: -a When used with -g, print status for geoms without providers. -g Report statuses for geoms instead of providers. -s Produce script-friendly output. load Load the kernel module that implements the given class. This command is only available if the class does not yet exist in the kernel and the file geom_<class>.ko can be found in one of the directories specified in kern.module_path sysctl. unload Unload the kernel module which implements the given class. This command is only available if the given class is loaded as a kernel module. Class-specific commands are implemented as shared libraries which are stored in /lib/geom/ directory and are loaded via dlopen(3) function when the class name is known. When a class-specific shared library exists, a direct utility should also be available under the name of gclass. Currently available classes which are aware of geom(8): o CACHE o CONCAT o ELI o JOURNAL o LABEL o MIRROR o MOUNTVER o MULTIPATH o NOP o PART o RAID o RAID3 o SCHED o SHSEC o STRIPE o VIRSTOR ENVIRONMENT
The following environment variables affect the execution of geom: GEOM_LIBRARY_PATH Specifies the path where shared libraries are stored instead of /lib/geom/. Multiple paths can be specified with a colon- separated list of paths. EXIT STATUS
Exit status is 0 on success, and 1 if the command fails. EXAMPLES
The following example shows how to set up a stripe on three disks for automatic configuration: geom stripe label -v -s 65536 data /dev/da0 /dev/da1 /dev/da2 or: gstripe label -v -s 65536 data /dev/da0 /dev/da1 /dev/da2 Print the list of all providers from the DISK class: geom disk list Unload a kernel module which implements the MD class: geom md unload SEE ALSO
libgeom(3), geom(4), gcache(8), gconcat(8), geli(8), gjournal(8), glabel(8), gmirror(8), gmountver(8), gmultipath(8), gnop(8), gpart(8), graid3(8), gsched(8), gshsec(8), gstripe(8), gvirstor(8) HISTORY
The geom utility appeared in FreeBSD 5.3. AUTHORS
Pawel Jakub Dawidek <pjd@FreeBSD.org> BSD
January 5, 2011 BSD

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GNOP(8) 						    BSD System Manager's Manual 						   GNOP(8)

NAME
gnop -- control utility for NOP GEOM class SYNOPSIS
gnop create [-v] [-e error] [-o offset] [-r rfailprob] [-s size] [-S secsize] [-w wfailprob] dev ... gnop configure [-v] [-e error] [-r rfailprob] [-w wfailprob] prov ... gnop destroy [-fv] prov ... gnop reset [-v] prov ... gnop list gnop status gnop load gnop unload DESCRIPTION
The gnop utility is used for setting up transparent providers on existing ones. Its main purpose is testing other GEOM classes, as it allows forced provider removal and I/O error simulation with a given probability. It also gathers the following statistics: number of read requests, number of write requests, number of bytes read and number of bytes written. In addition, it can be used as a good starting point for implementing new GEOM classes. The first argument to gnop indicates an action to be performed: create Set up a transparent provider on the given devices. If the operation succeeds, the new provider should appear with name /dev/<dev>.nop. The kernel module geom_nop.ko will be loaded if it is not loaded already. configure Configure existing transparent provider. At the moment it is only used for changing failure probability. destroy Turn off the given transparent providers. reset Reset statistics for the given transparent providers. list See geom(8). status See geom(8). load See geom(8). unload See geom(8). Additional options: -e error Specifies the error number to return on failure. -f Force the removal of the specified provider. -o offset Where to begin on the original provider. -r rfailprob Specifies read failure probability in percent. -s size Size of the transparent provider. -S secsize Sector size of the transparent provider. -w wfailprob Specifies write failure probability in percent. -v Be more verbose. SYSCTL VARIABLES
The following sysctl(8) variables can be used to control the behavior of the NOP GEOM class. The default value is shown next to each vari- able. kern.geom.nop.debug: 0 Debug level of the NOP GEOM class. This can be set to a number between 0 and 2 inclusive. If set to 0, minimal debug information is printed. If set to 1, basic debug information is logged along with the I/O requests that were returned as errors. If set to 2, the maximum amount of debug information is printed including all I/O requests. EXIT STATUS
Exit status is 0 on success, and 1 if the command fails. EXAMPLES
The following example shows how to create a transparent provider for disk /dev/da0 with 50% write failure probability, and how to destroy it. gnop create -v -w 50 da0 gnop destroy -v da0.nop The traffic statistics for the given transparent providers can be obtained with the list command. The example below shows the number of bytes written with newfs(8): gnop create da0 newfs /dev/da0.nop gnop list SEE ALSO
geom(4), geom(8) HISTORY
The gnop utility appeared in FreeBSD 5.3. AUTHORS
Pawel Jakub Dawidek <pjd@FreeBSD.org> BSD
April 14, 2013 BSD

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