nbdkit-partition-filter - Man Page

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

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.

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).

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

$filterdir/nbdkit-partition-filter.so

The filter.

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

nbdkit-partition-filter first appeared in nbdkit 1.2.

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).

Eric Blake

Richard W.M. Jones

Copyright Red Hat

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nbdkit(1), nbdkit-ext2-filter(1), nbdkit-filter(3), nbdkit-linuxdisk-plugin(1), nbdkit-luks-filter(1), nbdkit-lzip-filter(1), nbdkit-nbd-plugin(1), nbdkit-offset-filter(1), nbdkit-partitioning-plugin(1), nbdkit-protect-filter(1), nbdkit-release-notes-1.12(1), nbdkit-release-notes-1.36(1), nbdkit-release-notes-1.8(1), nbdkit-truncate-filter(1).