ceph/src/ceph-volume/ceph_volume/devices/lvm/zap.py

   1 import argparse
   2 import logging
   3
   4 from textwrap import dedent
   5
   6 from ceph_volume import decorators, terminal, process
   7 from ceph_volume.api import lvm as api
   8 from ceph_volume.util import system, encryption, disk
   9
  10 logger = logging.getLogger(__name__)
  11 mlogger = terminal.MultiLogger(__name__)
  12
  13
  14 def wipefs(path):
  15     """
  16     Removes the filesystem from an lv or partition.
  17     """
  18     process.run([
  19         'wipefs',
  20         '--all',
  21         path
  22     ])
  23
  24
  25 def zap_data(path):
  26     """
  27     Clears all data from the given path. Path should be
  28     an absolute path to an lv or partition.
  29
  30     10M of data is written to the path to make sure that
  31     there is no trace left of any previous Filesystem.
  32     """
  33     process.run([
  34         'dd',
  35         'if=/dev/zero',
  36         'of={path}'.format(path=path),
  37         'bs=1M',
  38         'count=10',
  39     ])
  40
  41
  42 class Zap(object):
  43
  44     help = 'Removes all data and filesystems from a logical volume or partition.'
  45
  46     def __init__(self, argv):
  47         self.argv = argv
  48
  49     @decorators.needs_root
  50     def zap(self, args):
  51         device = args.device
  52         lv = api.get_lv_from_argument(device)
  53         if lv:
  54             # we are zapping a logical volume
  55             path = lv.lv_path
  56         else:
  57             # we are zapping a partition
  58             #TODO: ensure device is a partition
  59             path = device
  60
  61         mlogger.info("Zapping: %s", path)
  62
  63         # check if there was a pv created with the
  64         # name of device
  65         pv = api.get_pv(pv_name=device)
  66         if pv:
  67             vg_name = pv.vg_name
  68             lv = api.get_lv(vg_name=vg_name)
  69
  70         dmcrypt = False
  71         dmcrypt_uuid = None
  72         if lv:
  73             osd_path = "/var/lib/ceph/osd/{}-{}".format(lv.tags['ceph.cluster_name'], lv.tags['ceph.osd_id'])
  74             dmcrypt_uuid = lv.lv_uuid
  75             dmcrypt = lv.encrypted
  76             if system.path_is_mounted(osd_path):
  77                 mlogger.info("Unmounting %s", osd_path)
  78                 system.unmount(osd_path)
  79         else:
  80             # we're most likely dealing with a partition here, check to
  81             # see if it was encrypted
  82             partuuid = disk.get_partuuid(device)
  83             if encryption.status("/dev/mapper/{}".format(partuuid)):
  84                 dmcrypt_uuid = partuuid
  85                 dmcrypt = True
  86
  87         if dmcrypt and dmcrypt_uuid:
  88             dmcrypt_path = "/dev/mapper/{}".format(dmcrypt_uuid)
  89             mlogger.info("Closing encrypted path %s", dmcrypt_path)
  90             encryption.dmcrypt_close(dmcrypt_path)
  91
  92         if args.destroy and pv:
  93             logger.info("Found a physical volume created from %s, will destroy all it's vgs and lvs", device)
  94             vg_name = pv.vg_name
  95             mlogger.info("Destroying volume group %s because --destroy was given", vg_name)
  96             api.remove_vg(vg_name)
  97             mlogger.info("Destroying physical volume %s because --destroy was given", device)
  98             api.remove_pv(device)
  99         elif args.destroy and not pv:
 100             mlogger.info("Skipping --destroy because no associated physical volumes are found for %s", device)
 101
 102         wipefs(path)
 103         zap_data(path)
 104
 105         if lv and not pv:
 106             # remove all lvm metadata
 107             lv.clear_tags()
 108
 109         terminal.success("Zapping successful for: %s" % path)
 110
 111     def main(self):
 112         sub_command_help = dedent("""
 113         Zaps the given logical volume, raw device or partition for reuse by ceph-volume.
 114         If given a path to a logical volume it must be in the format of vg/lv. Any
 115         filesystems present on the given device, vg/lv, or partition will be removed and
 116         all data will be purged.
 117
 118         If the logical volume, raw device or partition is being used for any ceph related
 119         mount points they will be unmounted.
 120
 121         However, the lv or partition will be kept intact.
 122
 123         Example calls for supported scenarios:
 124
 125           Zapping a logical volume:
 126
 127               ceph-volume lvm zap {vg name/lv name}
 128
 129           Zapping a partition:
 130
 131               ceph-volume lvm zap /dev/sdc1
 132
 133         If the --destroy flag is given and you are zapping a raw device or partition
 134         then all vgs and lvs that exist on that raw device or partition will be destroyed.
 135
 136         This is especially useful if a raw device or partition was used by ceph-volume lvm create
 137         or ceph-volume lvm prepare commands previously and now you want to reuse that device.
 138
 139         For example:
 140
 141           ceph-volume lvm zap /dev/sda --destroy
 142
 143         If the --destroy flag is given and you are zapping an lv then the lv is still
 144         kept intact for reuse.
 145
 146         """)
 147         parser = argparse.ArgumentParser(
 148             prog='ceph-volume lvm zap',
 149             formatter_class=argparse.RawDescriptionHelpFormatter,
 150             description=sub_command_help,
 151         )
 152
 153         parser.add_argument(
 154             'device',
 155             metavar='DEVICE',
 156             nargs='?',
 157             help='Path to an lv (as vg/lv), partition (as /dev/sda1) or device (as /dev/sda)'
 158         )
 159         parser.add_argument(
 160             '--destroy',
 161             action='store_true',
 162             default=False,
 163             help='Destroy all volume groups and logical volumes if you are zapping a raw device or partition',
 164         )
 165         if len(self.argv) == 0:
 166             print(sub_command_help)
 167             return
 168         args = parser.parse_args(self.argv)
 169         self.zap(args)