cvmkfile(1) [osx man page]
cvmkfile(1) cvmkfile(1) NAME
cvmkfile - Create a pre-allocated file SYNOPSIS
cvmkfile [-k <key>] [-p] [-s] [-w] [-z] <size>[k|m|g] <filename> DESCRIPTION
cvmkfile can be used to pre-allocate a file on the Xsan volume. This is useful and preferable when preparing a file for use in a real-time or streaming environment as the entire file is represented in only one file system extent. Additionally, a file can be placed onto a specific storage pool by specifying the <key> value, which is used as the affin- ity locator. See cvfs_config(4) for more details about affinities. USAGE
The -k <key> optionally tells the file system where to place the data file. If an Affinity Key is specified, the file is placed on storage pools that are specified to support this key. If there is no storage pool with the key specified, then the file is placed in non-exclusive data pools. If there are no non-exclusive data pools, then ENOSPC (no space) is returned. The -p option forces the allocation and any subsequent expansions to be fitted "perfectly" as multiples of the InodeExpandMin configuration parameter. The allocation extent will always line up on and be a per- fect multiple of the blocks specified in InodeExpandMin. The -s option forces the allocation to line up on the beginning block modulus of the storage pool. This can help performance in situations where the I/O size perfectly spans the width of the storage pool's disks. The -w option sets the file size to be equal to <size>. Without this option the blocks are allocated but the size is set to zero. NOTE: Unless the -z option is used, the new file will contain undefined data. Using the -w option is not recommended unless absolutely needed. The -z option causes the file to be physically zeroed out. This can take a significant amount of time. The <size> argument specifies the number of bytes, kilobytes(k), megabytes(m) or gigabytes(g) to allocate for the file. There is no guarantee that all requested space will be allocated. If there is insufficient contiguous available space to satisfy the requested amount then a "best effort" will be performed. In this case a success value is returned even though not all of the requested amount is allocated to the file. Even though the allocation may not be fully satisfied, if the -w option is specified then the file size will still reflect the requested <size> value. EXAMPLES
Make a file of one gigabyte with zero length. Allocate it on a storage pool that favors the media type 6100_n8. rock # cvmkfile -k 6100_n8 1g foobar SEE ALSO
cvfs_config(4), cvmkdir(1) Xsan File System December 2005 cvmkfile(1)
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Sys::Virt::StoragePool(3) User Contributed Perl Documentation Sys::Virt::StoragePool(3) NAME
Sys::Virt::StoragePool - Represent & manage a libvirt storage pool DESCRIPTION
The "Sys::Virt::StoragePool" module represents a storage pool managed by libvirt. There are a variety of storage pool implementations for LVM, Local directories/filesystems, network filesystems, disk partitioning, iSCSI, and SCSI. METHODS
my $uuid = $pool->get_uuid() Returns a 16 byte long string containing the raw globally unique identifier (UUID) for the storage pool. my $uuid = $pool->get_uuid_string() Returns a printable string representation of the raw UUID, in the format 'XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX'. my $name = $pool->get_name() Returns a string with a locally unique name of the storage pool $pool->is_active() Returns a true value if the storage pool is currently running $pool->is_persistent() Returns a true value if the storage pool has a persistent configuration file defined my $xml = $pool->get_xml_description() Returns an XML document containing a complete description of the storage pool's configuration $pool->create() Start a storage pool whose configuration was previously defined using the "define_storage_pool" method in Sys::Virt. $pool->undefine() Remove the configuration associated with a storage pool previously defined with the "define_storage pool" method in Sys::Virt. If the storage pool is running, you probably want to use the "shutdown" or "destroy" methods instead. $pool->destroy() Immediately terminate the machine, and remove it from the virtual machine monitor. The $pool handle is invalid after this call completes and should not be used again. $flag = $pool->get_autostart(); Return a true value if the storage pool is configured to automatically start upon boot. Return false, otherwise $pool->set_autostart($flag) Set the state of the autostart flag, which determines whether the storage pool will automatically start upon boot of the host OS $pool->refresh([$flags]); Refresh the storage pool state. Typically this will rescan the list of storage volumes. The $flags parameter is currently unused and if omitted defaults to zero. $pool->build([$flags]); Construct the storage pool if it does not exist. As an example, for a disk based storage pool this would ensure a partition table exists. The $flags parameter allows control over the build operation and if omitted defaults to zero. $pool->delete([$flags]); Delete the storage pool. The $flags parameter allows the data to be optionally wiped during delete and if omitted defaults to zero. $info = $pool->get_info() Retrieve information about the current storage pool state. The returned hash reference has the following keys state The current status of the storage pool. See constants later. capacity The total logical size of the storage pool allocation The current physical allocation of the storage pool available The available space for creation of new volumes. This may be less than the difference between capacity & allocation if there are sizing / metadata constraints for volumes my $nnames = $pool->num_of_storage_volumes() Return the number of running volumes in this storage pool. The value can be used as the "maxnames" parameter to "list_storage_vol_names". my @volNames = $pool->list_storage_vol_names($maxnames) Return a list of all volume names in this storage pool. The names can be used with the "get_volume_by_name" method. my @vols = $pool->list_volumes() Return a list of all volumes in the storage pool. The elements in the returned list are instances of the Sys::Virt::StorageVol class. This method requires O(n) RPC calls, so the "list_all_volumes" method is recommended as a more efficient alternative. my @volumes = $pool->list_all_volumes($flags) Return a list of all storage volumes associated with this pool. The elements in the returned list are instances of the Sys::Virt::StorageVol class. The $flags parameter can be used to filter the list of return storage volumes. my $vol = $pool->get_volume_by_name($name) Return the volume with a name of $name. The returned object is an instance of the Sys::Virt::StorageVol class. my $vol = $pool->create_volume($xml) Create a new volume based on the XML description passed into the $xml parameter. The returned object is an instance of the Sys::Virt::StorageVol class. If the optional "clonevol" is provided, data will be copied from that source volume my $vol = $pool->clone_volume($xml, $clonevol); Create a new volume based on the XML description passed into the $xml parameter. The returned object is an instance of the Sys::Virt::StorageVol class. The new volume will be populated with data from the specified clone source volume. CONSTANTS
The following sets of constants may be useful in dealing with some of the methods in this package POOL STATES The following constants are useful for interpreting the "state" key value in the hash returned by "get_info" Sys::Virt::StoragePool::STATE_INACTIVE The storage pool is not currently active Sys::Virt::StoragePool::STATE_BUILDING The storage pool is still being constructed and is not ready for use yet. Sys::Virt::StoragePool::STATE_RUNNING The storage pool is running and can be queried for volumes Sys::Virt::StoragePool::STATE_DEGRADED The storage pool is running, but its operation is degraded due to a failure. Sys::Virt::StoragePool::STATE_INACCESSIBLE The storage pool is not currently accessible DELETION MODES Sys::Virt::StoragePool::DELETE_NORMAL Delete the pool without any attempt to scrub data Sys::Virt::StoragePool::DELETE_ZEROED Fill the allocated storage with zeros when deleting BUILD MODES Sys::Virt::StoragePool::BUILD_NEW Construct a new storage pool from constituent bits Sys::Virt::StoragePool::BUILD_RESIZE Resize an existing built storage pool preserving data where appropriate Sys::Virt::StoragePool::BUILD_REPAIR Repair an existing storage pool operating in degraded mode Sys::Virt::StoragePool::BUILD_NO_OVERWRITE Do not overwrite existing storage pool data Sys::Virt::StoragePool::BUILD_OVERWRITE Overwrite existing storage pool data XML DOCUMENTS The following constants are useful when requesting XML for storage pools Sys::Virt::StoragePool::XML_INACTIVE Return XML describing the inactive state of the storage pool. LIST FILTERING
The following constants are used to filter object lists Sys::Virt::StoragePool::LIST_ACTIVE Include storage pools which are active Sys::Virt::StoragePool::LIST_INACTIVE Include storage pools which are inactive Sys::Virt::StoragePool::LIST_AUTOSTART Include storage pools which are marked for autostart Sys::Virt::StoragePool::LIST_NO_AUTOSTART Include storage pools which are not marked for autostart Sys::Virt::StoragePool::LIST_PERSISTENT Include storage pools which are persistent Sys::Virt::StoragePool::LIST_TRANSIENT Include storage pools which are transient Sys::Virt::StoragePool::LIST_DIR Include directory storage pools Sys::Virt::StoragePool::LIST_DISK Include disk storage pools Sys::Virt::StoragePool::LIST_FS Include filesytem storage pools Sys::Virt::StoragePool::LIST_ISCSI Include iSCSI storage pools Sys::Virt::StoragePool::LIST_LOGICAL Include LVM storage pools Sys::Virt::StoragePool::LIST_MPATH Include multipath storage pools Sys::Virt::StoragePool::LIST_NETFS Include network filesystem storage pools Sys::Virt::StoragePool::LIST_RBD Include RBD storage pools Sys::Virt::StoragePool::LIST_SCSI Include SCSI storage pools Sys::Virt::StoragePool::LIST_SHEEPDOG Include sheepdog storage pools 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" perl v5.16.3 2013-07-30 Sys::Virt::StoragePool(3)