gstripe(8)

NAME

gstripe - control utility for striped devices

SYNOPSIS

gstripe create [-v] [-s stripesize] name prov prov ...
gstripe destroy [-fv] name ...
gstripe label [-hv] [-s stripesize] name prov prov ...
gstripe stop [-fv] name ...
gstripe clear [-v] prov ...
gstripe dump prov ...
gstripe list
gstripe status
gstripe load
gstripe unload

DESCRIPTION

The gstripe utility is used for setting up a stripe on two

or more disks.
The striped device can be configured using two different

methods:
``manual'' or ``automatic''. When using the ``manual''

method, no metadata are stored on the devices, so the striped device has to

be configured by hand every time it is needed. The ``automatic''

method uses ondisk metadata to detect devices. Once devices are labeled,

they will be
automatically detected and configured.

The first argument to gstripe indicates an action to be per

formed:

create Set up a striped device from the given devices

with speci

fied name. This is the ``manual'' method and

the stripe
will not exist after a reboot (see DESCRIPTION

above). The
kernel module geom_stripe.ko will be loaded if

it is not
loaded already.

label Set up a striped device from the given devices

with the

specified name. This is the ``automatic''

method, where
metadata are stored in every device's last sec

tor. The kernel module geom_stripe.ko will be loaded if it

is not loaded
already.

stop Turn off an existing striped device by its

name. This com

mand does not touch on-disk metadata!

destroy Same as stop.

clear Clear metadata on the given devices.

dump Dump metadata stored on the given devices.

list See geom(8).

status See geom(8).

load See geom(8).

unload See geom(8).

Additional options:

-f Force the removal of the specified

striped device.

-h Hardcode providers' names in metadata.

-s stripesize Specifies size of stripe block in

bytes. The

stripesize must be a multiple of the

largest sector
size of all the providers.

-v Be more verbose.

SYSCTL VARIABLES

The following sysctl(8) variables can be used to control the

behavior of
the STRIPE GEOM class. The default value is shown next to

each variable.

kern.geom.stripe.debug: 0

Debug level of the STRIPE GEOM class. This can be

set to a number between 0 and 3 inclusive. If set to 0 minimal

debug information is printed, and if set to 3 the maximum

amount of debug
information is printed.

kern.geom.stripe.fast: 0

If set to a non-zero value enable ``fast mode'' in

stead of the
normal ``economic mode''. Compared to ``economic

mode'', ``fast
mode'' uses more memory, but it is much faster for

smaller stripe
sizes. If enough memory cannot be allocated, STRIPE

will fall
back to ``economic mode''.

kern.geom.stripe.maxmem: 13107200

Maximum amount of memory that can be consumed by

``fast mode''
(in bytes). This sysctl(8) variable is read-only

and can only be
set as a tunable in loader.conf(5).

kern.geom.stripe.fast_failed

A count of how many times ``fast mode'' has failed

due to an
insufficient amount of memory. If this value is

large, you
should consider increasing the

kern.geom.stripe.maxmem value.

EXIT STATUS

Exit status is 0 on success, and 1 if the command fails.

EXAMPLES

The following example shows how to set up a striped device

from four
disks with a 128KB stripe size for automatic configuration,

create a file
system on it, and mount it:

gstripe label -v -s 131072 data /dev/da0 /dev/da1

/dev/da2 /dev/da3
newfs /dev/stripe/data
mount /dev/stripe/data /mnt
[...]
umount /mnt
gstripe stop data
gstripe unload

COMPATIBILITY

The gstripe interleave is in number of bytes, unlike ccdcon

fig(8) and
atacontrol(8) which use the number of sectors. A ccdcon

fig(8) ileave of
`128' is 64 KB (128 512B sectors). The same stripe inter

leave would be
specified as `65536' for gstripe.

SEE ALSO

geom(4), loader.conf(5), atacontrol(8), ccdconfig(8), ge

om(8), mount(8),
newfs(8), sysctl(8), umount(8), vinum(8)

HISTORY

The gstripe utility appeared in FreeBSD 5.3.

AUTHORS

Pawel Jakub Dawidek <pjd@FreeBSD.org>

BSD May 21, 2004

BSD