NAME

nbdkit-partition-filter - nbdkit partition filter

SYNOPSIS

 nbdkit --filter=partition plugin partition=PART [plugin-args...]

DESCRIPTION

nbdkit-partition-filter is a filter that limits requests to a single partition within a disk image that is served by another plugin.

Partition numbers are specified by the required partition parameter, and count from 1.

This works like the qemu-nbd -P option.

The opposite of this filter is nbdkit-partitioning-plugin(1) which adds a virtual partition table to a file or files.

PARAMETERS

partition=PART

The partition number to serve, counting from 1.

This parameter is required.

partition-sectorsize=SECTOR_SIZE

The default for this parameter is chosen according to the minimum block size advertised by the underlying device. If it is 512 or 4K, then the sector size is set to that. If the underlying device does not advertise a minimum block size, or it is something other than 512 or 4K, the default is 512 bytes.

The user may specify 512 or 4096 as the sector size manually via config.

However set, this parameter instructs the partition table logic to treat the underlying storage as having the indicated sector size. This is important for MBR and GPT logic using LBA (logical block addressing).

EXAMPLE

disk.img is a partitioned disk image (eg. a virtual machine disk image). To serve the first partition only use:

 nbdkit --filter=partition file disk.img partition=1

FILES

$filterdir/nbdkit-partition-filter.so

The filter.

Use nbdkit --dump-config to find the location of $filterdir.

VERSION

nbdkit-partition-filter first appeared in nbdkit 1.2.

SEE ALSO

nbdkit(1), nbdkit-file-plugin(1), nbdkit-filter(3), nbdkit-offset-filter(1), nbdkit-partitioning-plugin(1), nbdkit-protect-filter(1), nbdkit-truncate-filter(1), parted(8).

AUTHORS

Eric Blake

Richard W.M. Jones

COPYRIGHT

Copyright Red Hat

LICENSE

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.