1PVMOVE(8)                   System Manager's Manual                  PVMOVE(8)
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NAME

6       pvmove — move physical extents
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SYNOPSIS

9       pvmove  [--abort]  [--alloc  AllocationPolicy]  [--atomic]  [-b|--back‐
10       ground]   [--commandprofile   ProfileName]   [-d|--debug]   [-h|--help]
11       [-i|--interval  Seconds] [--noudevsync] [-v|--verbose] [-n|--name Logi‐
12       calVolume] [SourcePhysicalVolume[:PE[-PE]...]  [DestinationPhysicalVol‐
13       ume[:PE[-PE]...]...]]
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DESCRIPTION

16       pvmove allows you to move the allocated physical extents (PEs) on Sour‐
17       cePhysicalVolume to one or more other physical volumes (PVs).  You  can
18       optionally  specify  a  source LogicalVolume in which case only extents
19       used by that LV will be moved to free (or specified) extents on  Desti‐
20       nationPhysicalVolume(s).  If no DestinationPhysicalVolume is specified,
21       the normal allocation rules for the Volume Group are used.
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23       If pvmove gets interrupted for any reason (e.g.  the  machine  crashes)
24       then  run  pvmove again without any PhysicalVolume arguments to restart
25       any moves that were in progress from  the  last  checkpoint.   Alterna‐
26       tively use pvmove --abort at any time to abort.  The resulting location
27       of logical volumes after an abort is  issued  depends  on  whether  the
28       --atomic option was used when starting the pvmove process.
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30       You  can run more than one pvmove at once provided they are moving data
31       off different SourcePhysicalVolumes, but additional pvmoves will ignore
32       any  Logical  Volumes  already in the process of being changed, so some
33       data might not get moved.
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35       pvmove works as follows:
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37       1. A temporary 'pvmove' Logical Volume is created to store  details  of
38       all the data movements required.
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40       2.  Every Logical Volume in the Volume Group is searched for contiguous
41       data that need moving according to the  command  line  arguments.   For
42       each  piece  of  data  found,  a new segment is added to the end of the
43       pvmove LV.  This segment takes the form of a temporary mirror  to  copy
44       the data from the original location to a newly-allocated location.  The
45       original LV is updated to use the new temporary mirror segment  in  the
46       pvmove LV instead of accessing the data directly.
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48       3. The Volume Group metadata is updated on disk.
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50       4.  The  first  segment  of  the pvmove Logical Volume is activated and
51       starts to mirror the first part of the data.  Only one segment is  mir‐
52       rored at once as this is usually more efficient.
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54       5.  A daemon repeatedly checks progress at the specified time interval.
55       When it detects that the first temporary mirror is in-sync,  it  breaks
56       that  mirror  so that only the new location for that data gets used and
57       writes a checkpoint into the Volume Group metadata on  disk.   Then  it
58       activates the mirror for the next segment of the pvmove LV.
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60       6.  When  there are no more segments left to be mirrored, the temporary
61       Logical Volume is removed and the Volume Group metadata is  updated  so
62       that the Logical Volumes reflect the new data locations.
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64       Note that this new process cannot support the original LVM1 type of on-
65       disk metadata.  Metadata can be converted using vgconvert(8).
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67       If the --atomic option is used, a slightly different approach  is  used
68       for the move.  Again, a temporary 'pvmove' logical volume is created to
69       store the details of all the data movements required.   This  temporary
70       LV  contains all the segments of the various LVs that need to be moved.
71       However this time, an identical logical volume is allocated  that  con‐
72       tains  the  same number of segments and a mirror is created to copy the
73       contents from the first temporary LV to the second.   When  a  complete
74       copy  is accomplished, the temporary logical volumes are removed, leav‐
75       ing behind the segments on the  destination  physical  volume.   If  an
76       abort  is  issued during the move, all logical volumes being moved will
77       remain on the source physical volume.
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OPTIONS

81       See lvm(8) for common options.
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83       --abort
84              Abort any moves in progress.  If the --atomic option was used to
85              start  the pvmove, all logical volumes will remain on the source
86              physical volume.  Otherwise, those segments that have  completed
87              the  move  will  stay  on the destination physical volume, while
88              those that have not will remain on the source physical volume.
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90       --atomic
91              Make the entire operation atomic.   That  is,  ensure  that  all
92              affected  logical  volumes are moved to the destination physical
93              volume together; unless the move has been aborted.  If the  move
94              has  been aborted, all logical volumes will remain on the source
95              physical volume.
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97       --noudevsync
98              Disable udev synchronisation. The  process  will  not  wait  for
99              notification  from  udev.   It will continue irrespective of any
100              possible udev processing in the background.  You should only use
101              this if udev is not running or has rules that ignore the devices
102              LVM2 creates.
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104       -b, --background
105              Run the daemon in the background.
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107       -i, --interval Seconds
108              Report progress as a percentage at regular intervals.
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110       -n, --name LogicalVolume
111              Move only the extents belonging to  LogicalVolume  from  Source‐
112              PhysicalVolume  instead of all allocated extents to the destina‐
113              tion physical volume(s).
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Examples

117       To move all Physical Extents that are used by simple Logical Volumes on
118       /dev/sdb1 to free Physical Extents elsewhere in the Volume Group use:
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120       pvmove /dev/sdb1
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122       Additionally,  a specific destination device /dev/sdc1 can be specified
123       like this:
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125       pvmove /dev/sdb1 /dev/sdc1
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127       To perform the action only on extents belonging to the  single  Logical
128       Volume lvol1 do this:
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130       pvmove -n lvol1 /dev/sdb1 /dev/sdc1
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132       Rather than moving the contents of the entire device, it is possible to
133       move a range of Physical Extents - for example  numbers  1000  to  1999
134       inclusive on /dev/sdb1 - like this:
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136       pvmove /dev/sdb1:1000-1999
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138       A range can also be specified as start+length, so
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140       pvmove /dev/sdb1:1000+1000
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142       also refers to 1000 Physical Extents starting from Physical Extent num‐
143       ber 1000.  (Counting starts from 0, so this refers to the 1001st to the
144       2000th inclusive.)
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146       To  move a range of Physical Extents to a specific location (which must
147       have sufficient free extents) use the form:
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149       pvmove /dev/sdb1:1000-1999 /dev/sdc1
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151       or
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153       pvmove /dev/sdb1:1000-1999 /dev/sdc1:0-999
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155       If the source and destination are on the same disk, the anywhere  allo‐
156       cation policy would be needed, like this:
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158       pvmove --alloc anywhere /dev/sdb1:1000-1999 /dev/sdb1:0-999
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160       The  part  of  a  specific  Logical Volume present within in a range of
161       Physical Extents can also be picked out and moved, like this:
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163       pvmove -n lvol1 /dev/sdb1:1000-1999 /dev/sdc1
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SEE ALSO

166       lvm(8), vgconvert(8) pvs(8)
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170Sistina Software UKLVM TOOLS 2.02.143(2)-RHEL6 (2016-12-13)          PVMOVE(8)
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