1PVCREATE(8) System Manager's Manual PVCREATE(8)
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6 pvcreate - initialize a disk or partition for use by LVM
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9 pvcreate [-d|--debug] [-h|--help] [-t|--test] [-v|--verbose] [--ver‐
10 sion] [-f[f]|--force [--force]] [-y|--yes] [--labelsector] [-M|--meta‐
11 datatype type] [--[pv]metadatacopies #copies] [--metadatasize size]
12 [--metadataignore {y|n}] [--dataalignment alignment] [--dataalign‐
13 mentoffset alignment_offset] [--restorefile file] [--norestorefile]
14 [--setphysicalvolumesize size] [-u|--uuid uuid] [-Z|--zero {y|n}] Phys‐
15 icalVolume [PhysicalVolume...]
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18 pvcreate initializes PhysicalVolume for later use by the Logical Volume
19 Manager (LVM). Each PhysicalVolume can be a disk partition, whole
20 disk, meta device, or loopback file. For DOS disk partitions, the par‐
21 tition id should be set to 0x8e using fdisk(8), cfdisk(8), or a equiva‐
22 lent. For whole disk devices only the partition table must be erased,
23 which will effectively destroy all data on that disk. This can be done
24 by zeroing the first sector with:
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26 dd if=/dev/zero of=PhysicalVolume bs=512 count=1
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28 Continue with vgcreate(8) to create a new volume group on PhysicalVol‐
29 ume, or vgextend(8) to add PhysicalVolume to an existing volume group.
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32 See lvm(8) for common options.
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34 -f, --force
35 Force the creation without any confirmation. You can not recre‐
36 ate (reinitialize) a physical volume belonging to an existing
37 volume group. In an emergency you can override this behaviour
38 with -ff.
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40 -u, --uuid uuid
41 Specify the uuid for the device. Without this option, pvcreate
42 generates a random uuid. All of your physical volumes must have
43 unique uuids. You need to use this option before restoring a
44 backup of LVM metadata onto a replacement device - see vgcfgre‐
45 store(8). As such, use of --restorefile is compulsory unless
46 the --norestorefile is used.
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48 -y, --yes
49 Answer yes to all questions.
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51 -Z, --zero y|n
52 Whether or not the first 4 sectors (2048 bytes) of the device
53 should be wiped. If this option is not given, the default is to
54 wipe these sectors unless either or both of the --restorefile or
55 --uuid options were specified.
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58 LVM2 introduces a new format for storing metadata on disk. This new
59 format is more efficient and resilient than the format the original
60 version of LVM used and offers the advanced user greater flexibility
61 and control.
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63 The new format may be selected on the command line with -M2 or by set‐
64 ting format = "lvm2" in the global section of lvm.conf. Each physical
65 volume in the same volume group must use the same format, but different
66 volume groups on a machine may use different formats simultaneously:
67 the tools can handle both formats. Additional formats can be added as
68 shared libraries.
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70 Additional tools for manipulating the locations and sizes of metadata
71 areas will be written in due course. Use the verbose/debug options on
72 the tools to see where the metadata areas are placed.
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74 --metadatasize size
75 The approximate amount of space to be set aside for each meta‐
76 data area. (The size you specify may get rounded.)
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78 --dataalignment alignment
79 Align the start of the data to a multiple of this number. You
80 should also specify an appropriate PhysicalExtentSize when cre‐
81 ating the Volume Group with vgcreate.
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83 To see the location of the first Physical Extent of an existing
84 Physical Volume use pvs -o +pe_start . It will be a multiple of
85 the requested alignment. In addition it may be shifted by
86 alignment_offset from data_alignment_offset_detection (if
87 enabled in lvm.conf) or --dataalignmentoffset.
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89 --dataalignmentoffset alignment_offset
90 Shift the start of the data area by this additional align‐
91 ment_offset.
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93 --[pv]metadatacopies copies
94 The number of metadata areas to set aside on each PV. Currently
95 this can be 0, 1 or 2. If set to 2, two copies of the volume
96 group metadata are held on the PV, one at the front of the PV
97 and one at the end. If set to 1 (the default), one copy is kept
98 at the front of the PV (starting in the 5th sector). If set to
99 0, no copies are kept on this PV - you might wish to use this
100 with VGs containing large numbers of PVs. But if you do this
101 and then later use vgsplit you must ensure that each VG is still
102 going to have a suitable number of copies of the metadata after
103 the split!
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105 --metadataignore y|n
106 Ignore or un-ignore metadata areas on this physical volume. The
107 default is "n". This setting can be changed with pvchange. If
108 metadata areas on a physical volume are ignored, LVM will not
109 not store metadata in the metadata areas present on this Physi‐
110 cal Volume. Metadata areas cannot be created or extended after
111 Logical Volumes have been allocated on the device. If you do not
112 want to store metadata on this device, it is still wise always
113 to allocate a metadata area in case you need it in the future
114 and to use this option to instruct LVM2 to ignore it.
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116 --restorefile file
117 In conjunction with --uuid, this extracts the location and size
118 of the data on the PV from the file (produced by vgcfgbackup)
119 and ensures that the metadata that the program produces is con‐
120 sistent with the contents of the file i.e. the physical extents
121 will be in the same place and not get overwritten by new meta‐
122 data. This provides a mechanism to upgrade the metadata format
123 or to add/remove metadata areas. Use with care. See also vgcon‐
124 vert(8).
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126 --norestorefile
127 In conjunction with --uuid, this allows a uuid to be specified
128 without also requiring that a backup of the metadata be pro‐
129 vided.
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131 --labelsector sector
132 By default the PV is labelled with an LVM2 identifier in its
133 second sector (sector 1). This lets you use a different sector
134 near the start of the disk (between 0 and 3 inclusive - see
135 LABEL_SCAN_SECTORS in the source). Use with care.
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137 --setphysicalvolumesize size
138 Overrides the automatically-detected size of the PV. Use with
139 care.
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142 Initialize partition #4 on the third SCSI disk and the entire fifth
143 SCSI disk for later use by LVM:
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145 pvcreate /dev/sdc4 /dev/sde
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147 If the 2nd SCSI disk is a 4KB sector drive that compensates for windows
148 partitioning (sector 7 is the lowest aligned logical block, the 4KB
149 sectors start at LBA -1, and consequently sector 63 is aligned on a 4KB
150 boundary) manually account for this when initializing for use by LVM:
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152 pvcreate --dataalignmentoffset 7s /dev/sdb
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156 lvm.conf(5), lvm(8), vgcreate(8), vgextend(8), lvcreate(8), cfdisk(8),
157 fdisk(8), losetup(8), mdadm(8), vgcfgrestore(8), vgconvert(8)
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161Sistina Software UK LVM TOOLS 2.02.84(2) (2011-02-09) PVCREATE(8)