NAME¶nbdkit-file-plugin - nbdkit file plugin
nbdkit file [file=]FILENAME
DESCRIPTION¶"nbdkit-file-plugin" is a file serving plugin for nbdkit(1).
It serves the named "FILENAME" over NBD. Local block devices (eg. /dev/sda) may also be served.
To concatenate multiple files, use nbdkit-split-plugin(1).
If you want to expose a file that resides on a file system known to have poor lseek(2) performance when searching for holes ("tmpfs" is known to be one such file system), you can use nbdkit-noextents-filter(1) to avoid the penalty of probing for holes.
- Serve the file named "FILENAME". A local
block device name can also be used here.
This parameter is required.
"file=" is a magic config key and may be omitted in most cases. See "Magic parameters" in nbdkit(1).
- These plugin parameters have been moved to the nbdkit-delay-filter(1) filter. Modify the command line to add --filter=delay in order to use these parameters.
DUMP-PLUGIN OUTPUT¶You can obtain extra information about how the file plugin was compiled by doing:
nbdkit file --dump-plugin
Some of the fields which may appear are listed below. Note these are for information only and may be changed or removed at any time in the future.
- If both set, the plugin may be able to efficiently zero ranges of block devices, where the driver and block device itself supports this.
- If set, the plugin may be able to punch holes (make sparse) files and block devices.
- If set, the plugin may be able to efficiently zero ranges of files and block devices.
- -D file.zero=1
- This enables very verbose debugging of the NBD zero request. This can be used to tell if the file plugin is able to zero ranges in the file or block device efficiently or not.
SEE ALSO¶nbdkit(1), nbdkit-plugin(3), nbdkit-split-plugin(1), nbdkit-partitioning-plugin(1), nbdkit-noextents-filter(1).
Richard W.M. Jones
COPYRIGHT¶Copyright (C) 2013-2018 Red Hat Inc.
LICENSE¶Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
- Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
- Neither the name of Red Hat nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
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