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 on-disk 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 performed:

create

Set up a striped device from the given devices with specified 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 sector. 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 command 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” instead 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 ccdconfig(8) which use the number of sectors. A ccdconfig(8) ileave of ‘ 128’ is 64 KB (128 512B sectors). The same stripe interleave would be specified as ‘ 65536’ for gstripe.

SEE ALSO

geom(4), loader.conf(5), ccdconfig(8), geom(8), gvinum(8), mount(8), newfs(8), sysctl(8), umount(8)

HISTORY

The gstripe utility appeared in FreeBSD 5.3.

AUTHORS

Pawel Jakub Dawidek <pjd@FreeBSD.org>