| Sys::Virt::StorageVol(3) | User Contributed Perl Documentation | Sys::Virt::StorageVol(3) |
NAME¶
Sys::Virt::StorageVol - Represent & manage a libvirt storage volume
DESCRIPTION¶
The "Sys::Virt::StorageVol" module represents a storage volume managed by libvirt. A storage volume is always associated with a containing storage pool ("Sys::Virt::StoragePool").
METHODS¶
- my $name = $vol->get_name()
- Returns a string with a locally unique name of the storage vol
- my $name = $vol->get_key()
- Returns a string with a globally unique key for the storage vol
- my $name = $vol->get_path()
- Returns a string with a locally unique file path of the storage vol
- my $xml = $vol->get_xml_description()
- Returns an XML document containing a complete description of the storage vol's configuration
- $vol->delete($flags)
- Immediately delete the storage volume freeing its storage resources. The "flags" parameter indicates any special action to be taken when deleting the volume.
- $vol->resize($newcapacity, $flags=0)
- Adjust the size of the storage volume. The $newcapacity value semantics depend on the $flags parameter. If $flags specifies "RESIZE_DELTA" then the $newcapacity is relative to the current size. If $flags specifies "RESIZE_SHRINK" then the $newcapacity value is the amount of space to remove
- $vol->wipe($flags = 0)
- Clear the data in the storage volume to avoid future information leak. The "flags" parameter is currently unused and defaults to zero.
- $vol->wipe_pattern($algorithm, $flags = 0)
- Clear the data in the storage volume to avoid future information leak. The $algorithm parameter specifies the data pattern used to erase data, and should be one of the WIPE ALGORITHM CONSTANTS listed later. The "flags" parameter is currently unused and defaults to zero.
- my $info = $vol->get_info($flags = 0)
- Retrieve live information about the storage volume. The returned $info hash reference contains three keys. "type" indicates whether the volume is a file or block device. "capacity" provides the maximum logical size of the volume. "allocation" provides the current physical usage of the volume. The allocation may be less than the capacity for sparse, or grow-on-demand volumes. The allocation may also be larger than the capacity, if there is a metadata overhead for the volume format. $flags may take one of the values
- Sys::Virt::StorageVol::USE_ALLOCATION
- Return the current allocation in allocation
- Sys::Virt::StorageVol::GET_PHYSICAL
- Return the physical size in allocation
- $vol->download($st, $offset, $length, $flags=0);
- Download data from $vol using the stream $st. If $offset and $length are non-zero, then restrict data to the specified volume byte range. The $flags accept the following values:
- Sys::Virt::StorageVol::VOL_DOWNLOAD_SPARSE_STREAM
- If this flag is is set in @flags effective transmission of holes is enabled. This assumes using the stream $st with combination of "sparse_recv_all" or "recv($flags = VIR_STREAM_RECV_STOP_AT_HOLE)" for honouring holes sent by server.
- $vol->upload($st, $offset, $length, $flags=0);
- Upload data to $vol using the stream $st. If $offset and $length are non-zero, then restrict data to the specified volume byte range. The $flags accept the following values:
- Sys::Virt::StorageVol::VOL_UPLOAD_SPARSE_STREAM
- If this is set in $flags effective transmission of holes is enabled. This assumes using the stream $st with combination of "sparse_send_all" or "send_hole" to preserve source file sparseness.
CONSTANTS¶
The following sets of constants are useful when dealing with storage volumes
VOLUME TYPES¶
The following constants are useful for interpreting the "type" field in the hash returned by the "get_info" method
- Sys::Virt::StorageVol::TYPE_FILE
- The volume is a plain file
- Sys::Virt::StorageVol::TYPE_BLOCK
- The volume is a block device
- Sys::Virt::StorageVol::TYPE_DIR
- The volume is a directory
- Sys::Virt::StorageVol::TYPE_NETWORK
- The volume is a network source
- Sys::Virt::StorageVol::TYPE_NETDIR
- The volume is a network directory
- Sys::Virt::StorageVol::TYPE_PLOOP
- The volume is a ploop directory
CREATE MODES¶
The following constants are useful for the "flags" parameter of the "create" method
- Sys::Virt::StorageVol::CREATE_PREALLOC_METADATA
- Preallocate header metadata when creating the volume.
- Sys::Virt::StorageVol::CREATE_REFLINK
- Perform lightweight reference copy
DELETE MODES¶
The following constants are useful for the "flags" parameter of the "delete" method
- Sys::Virt::StorageVol::DELETE_NORMAL
- Do a plain delete without any attempt to scrub data.
- Sys::Virt::StorageVol::DELETE_ZEROED
- Zero out current allocated blocks when deleteing the volume
- Sys::Virt::StorageVol::DELETE_WITH_SNAPSHOTS
- Delete snapshots associated with the volume
WIPE ALGORITHM CONSTANTS¶
The following constants specify the algorithm for erasing data
- Sys::Virt::StorageVol::WIPE_ALG_BSI
- 9-pass method recommended by the German Center of Security in Information Technologies
- Sys::Virt::StorageVol::WIPE_ALG_DOD
- 4-pass Dod 5220.22-M section, 8-306 procedure
- Sys::Virt::StorageVol::WIPE_ALG_GUTMANN
- The canonical 35-pass sequence
- Sys::Virt::StorageVol::WIPE_ALG_NNSA
- 4-pass NNSA Policy Letter NAP-14.1-C (XVI-8)
- Sys::Virt::StorageVol::WIPE_ALG_PFITZNER7
- 7-pass random
- Sys::Virt::StorageVol::WIPE_ALG_PFITZNER33
- 33-pass random
- Sys::Virt::StorageVol::WIPE_ALG_RANDOM
- 1-pass random
- Sys::Virt::StorageVol::WIPE_ALG_SCHNEIER
- 7-pass method described by Bruce Schneier in "Applied Cryptography" (1996)
- Sys::Virt::StorageVol::WIPE_ALG_ZERO
- 1-pass, all zeroes
- Sys::Virt::StorageVol::WIPE_ALG_TRIM
- 1-pass, trim all data on the volume by using TRIM or DISCARD
VOLUME RESIZE CONSTANTS
The following constants control how storage volumes can be resized
- Sys::Virt::StorageVol::RESIZE_ALLOCATE
- Fully allocate the extra space required during resize
- Sys::Virt::StorageVol::RESIZE_DELTA
- Treat the new capacity as a delta to the current capacity
- Sys::Virt::StorageVol::RESIZE_SHRINK
- Treat the new capacity as an amount to remove from the capacity
AUTHORS¶
Daniel P. Berrange <berrange@redhat.com>
COPYRIGHT¶
Copyright (C) 2006-2009 Red Hat Copyright (C) 2006-2009 Daniel P. Berrange
LICENSE¶
This program is free software; you can redistribute it and/or modify it under the terms of either the GNU General Public License as published by the Free Software Foundation (either version 2 of the License, or at your option any later version), or, the Artistic License, as specified in the Perl README file.
SEE ALSO¶
Sys::Virt, Sys::Virt::Error, "http://libvirt.org"
| 2018-10-31 | perl v5.16.3 |