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#!/usr/bin/python |
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# |
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|
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# Copyright (C) 2006, 2007, 2011, 2012 Google Inc. |
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# |
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# This program is free software; you can redistribute it and/or modify |
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# it under the terms of the GNU General Public License as published by |
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# the Free Software Foundation; either version 2 of the License, or |
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# (at your option) any later version. |
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# |
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# This program is distributed in the hope that it will be useful, but |
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# WITHOUT ANY WARRANTY; without even the implied warranty of |
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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# General Public License for more details. |
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# |
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# You should have received a copy of the GNU General Public License |
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# along with this program; if not, write to the Free Software |
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
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# 02110-1301, USA. |
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|
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|
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"""Program which configures LVM on the Ganeti nodes. |
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|
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This program wipes disks and creates a volume group on top of them. It |
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can also show disk information to help you decide which disks you want |
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to wipe. |
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|
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The error handling is done by raising our own exceptions from most of |
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the functions; these exceptions then handled globally in the main() |
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function. The exceptions that each function can raise are not |
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documented individually, since almost every error path ends in a |
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raise. |
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|
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Another two exceptions that are handled globally are IOError and |
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OSError. The idea behind this is, since we run as root, we should |
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usually not get these errors, but if we do it's most probably a system |
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error, so they should be handled and the user instructed to report |
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them. |
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|
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""" |
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|
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|
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import os |
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import sys |
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import optparse |
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import time |
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import errno |
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import re |
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|
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from ganeti.utils import RunCmd, ReadFile |
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from ganeti import constants |
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from ganeti import cli |
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from ganeti import compat |
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|
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USAGE = ("\tlvmstrap diskinfo\n" |
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"\tlvmstrap [--vg-name=NAME] [--allow-removable]" |
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" { --alldisks | --disks DISKLIST } [--use-sfdisk]" |
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" create") |
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|
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verbose_flag = False |
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|
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#: Supported disk types (as prefixes) |
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SUPPORTED_TYPES = [ |
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"hd", |
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"sd", |
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"md", |
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"ubd", |
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] |
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|
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#: Excluded filesystem types |
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EXCLUDED_FS = compat.UniqueFrozenset([ |
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"nfs", |
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"nfs4", |
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"autofs", |
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"tmpfs", |
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"proc", |
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"sysfs", |
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"usbfs", |
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"devpts", |
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]) |
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|
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#: A regular expression that matches partitions (must be kept in sync |
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# with L{SUPPORTED_TYPES} |
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PART_RE = re.compile("^((?:h|s|m|ub)d[a-z]{1,2})[0-9]+$") |
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|
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#: Minimum partition size to be considered (1 GB) |
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PART_MINSIZE = 1024 * 1024 * 1024 |
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MBR_MAX_SIZE = 2 * (10 ** 12) |
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|
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|
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class Error(Exception): |
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"""Generic exception""" |
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pass |
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|
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|
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class ProgrammingError(Error): |
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"""Exception denoting invalid assumptions in programming. |
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|
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This should catch sysfs tree changes, or otherwise incorrect |
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assumptions about the contents of the /sys/block/... directories. |
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|
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""" |
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pass |
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|
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|
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class SysconfigError(Error): |
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"""Exception denoting invalid system configuration. |
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|
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If the system configuration is somehow wrong (e.g. /dev files |
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missing, or having mismatched major/minor numbers relative to |
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/sys/block devices), this exception will be raised. |
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|
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This should usually mean that the installation of the Xen node |
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failed in some steps. |
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|
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""" |
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pass |
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|
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|
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class PrereqError(Error): |
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"""Exception denoting invalid prerequisites. |
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|
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If the node does not meet the requirements for cluster membership, this |
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exception will be raised. Things like wrong kernel version, or no |
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free disks, etc. belong here. |
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|
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This should usually mean that the build steps for the Xen node were |
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not followed correctly. |
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|
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""" |
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pass |
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|
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|
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class OperationalError(Error): |
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"""Exception denoting actual errors. |
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|
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Errors during the bootstrapping are signaled using this exception. |
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|
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""" |
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pass |
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|
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|
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class ParameterError(Error): |
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"""Exception denoting invalid input from user. |
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|
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Wrong disks given as parameters will be signaled using this |
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exception. |
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|
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""" |
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pass |
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|
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|
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def Usage(): |
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"""Shows program usage information and exits the program. |
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|
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""" |
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print >> sys.stderr, "Usage:" |
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print >> sys.stderr, USAGE |
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sys.exit(2) |
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|
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|
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def ParseOptions(): |
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"""Parses the command line options. |
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|
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In case of command line errors, it will show the usage and exit the |
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program. |
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|
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@rtype: tuple |
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@return: a tuple of (options, args), as returned by |
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OptionParser.parse_args |
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|
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""" |
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global verbose_flag # pylint: disable=W0603 |
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|
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parser = optparse.OptionParser(usage="\n%s" % USAGE, |
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version="%%prog (ganeti) %s" % |
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constants.RELEASE_VERSION) |
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|
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parser.add_option("--alldisks", dest="alldisks", |
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help="erase ALL disks", action="store_true", |
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default=False) |
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parser.add_option("-d", "--disks", dest="disks", |
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help="Choose disks (e.g. hda,hdg)", |
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metavar="DISKLIST") |
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parser.add_option(cli.VERBOSE_OPT) |
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parser.add_option("-r", "--allow-removable", |
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action="store_true", dest="removable_ok", default=False, |
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help="allow and use removable devices too") |
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parser.add_option("-g", "--vg-name", type="string", |
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dest="vgname", default="xenvg", metavar="NAME", |
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help="the volume group to be created [default: xenvg]") |
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parser.add_option("--use-sfdisk", dest="use_sfdisk", |
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action="store_true", default=False, |
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help="use sfdisk instead of parted") |
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|
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options, args = parser.parse_args() |
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if len(args) != 1: |
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Usage() |
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|
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verbose_flag = options.verbose |
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|
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return options, args |
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|
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|
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def IsPartitioned(disk): |
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"""Returns whether a given disk should be used partitioned or as-is. |
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|
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Currently only md devices are used as is. |
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|
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""" |
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return not (disk.startswith("md") or PART_RE.match(disk)) |
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|
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|
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def DeviceName(disk): |
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"""Returns the appropriate device name for a disk. |
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|
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For non-partitioned devices, it returns the name as is, otherwise it |
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returns the first partition. |
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|
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""" |
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if IsPartitioned(disk): |
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device = "/dev/%s1" % disk |
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else: |
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device = "/dev/%s" % disk |
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return device |
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|
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|
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def SysfsName(disk): |
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"""Returns the sysfs name for a disk or partition. |
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|
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""" |
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match = PART_RE.match(disk) |
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if match: |
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# this is a partition, which resides in /sys/block under a different name |
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disk = "%s/%s" % (match.group(1), disk) |
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return "/sys/block/%s" % disk |
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|
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|
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def ExecCommand(command): |
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"""Executes a command. |
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|
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This is just a wrapper around commands.getstatusoutput, with the |
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difference that if the command line argument -v has been given, it |
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will print the command line and the command output on stdout. |
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|
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@param command: the command line to be executed |
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@rtype: tuple |
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@return: a tuple of (status, output) where status is the exit status |
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and output the stdout and stderr of the command together |
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|
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""" |
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if verbose_flag: |
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print command |
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result = RunCmd(command) |
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if verbose_flag: |
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print result.output |
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return result |
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|
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|
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def CheckPrereq(): |
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"""Check the prerequisites of this program. |
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|
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It check that it runs on Linux 2.6, and that /sys is mounted and the |
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fact that /sys/block is a directory. |
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|
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""" |
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if os.getuid() != 0: |
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raise PrereqError("This tool runs as root only. Really.") |
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|
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osname, _, release, _, _ = os.uname() |
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if osname != "Linux": |
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raise PrereqError("This tool only runs on Linux" |
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" (detected OS: %s)." % osname) |
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|
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if not (release.startswith("2.6.") or release.startswith("3.")): |
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raise PrereqError("Wrong major kernel version (detected %s, needs" |
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" 2.6.* or 3.*)" % release) |
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|
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if not os.path.ismount("/sys"): |
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raise PrereqError("Can't find a filesystem mounted at /sys." |
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" Please mount /sys.") |
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|
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if not os.path.isdir("/sys/block"): |
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raise SysconfigError("Can't find /sys/block directory. Has the" |
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" layout of /sys changed?") |
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|
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if not os.path.ismount("/proc"): |
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raise PrereqError("Can't find a filesystem mounted at /proc." |
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" Please mount /proc.") |
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|
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if not os.path.exists("/proc/mounts"): |
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raise SysconfigError("Can't find /proc/mounts") |
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|
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|
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def CheckVGExists(vgname): |
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"""Checks to see if a volume group exists. |
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|
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@param vgname: the volume group name |
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|
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@return: a four-tuple (exists, lv_count, vg_size, vg_free), where: |
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- exists: True if the volume exists, otherwise False; if False, |
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all other members of the tuple are None |
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- lv_count: The number of logical volumes in the volume group |
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- vg_size: The total size of the volume group (in gibibytes) |
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- vg_free: The available space in the volume group |
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|
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""" |
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result = ExecCommand("vgs --nohead -o lv_count,vg_size,vg_free" |
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" --nosuffix --units g" |
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" --ignorelockingfailure %s" % vgname) |
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if not result.failed: |
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try: |
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lv_count, vg_size, vg_free = result.stdout.strip().split() |
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except ValueError: |
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# This means the output of vgdisplay can't be parsed |
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raise PrereqError("cannot parse output of vgs (%s)" % result.stdout) |
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else: |
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lv_count = vg_size = vg_free = None |
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|
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return not result.failed, lv_count, vg_size, vg_free |
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|
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|
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def CheckSysDev(name, devnum): |
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"""Checks consistency between /sys and /dev trees. |
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|
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In /sys/block/<name>/dev and /sys/block/<name>/<part>/dev are the |
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kernel-known device numbers. The /dev/<name> block/char devices are |
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created by userspace and thus could differ from the kernel |
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view. This function checks the consistency between the device number |
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read from /sys and the actual device number in /dev. |
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|
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Note that since the system could be using udev which removes and |
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recreates the device nodes on partition table rescan, we need to do |
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some retries here. Since we only do a stat, we can afford to do many |
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short retries. |
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|
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@param name: the device name, e.g. 'sda' |
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@param devnum: the device number, e.g. 0x803 (2051 in decimal) for sda3 |
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@raises SysconfigError: in case of failure of the check |
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|
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""" |
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path = "/dev/%s" % name |
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for _ in range(40): |
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if os.path.exists(path): |
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break |
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time.sleep(0.250) |
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else: |
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raise SysconfigError("the device file %s does not exist, but the block" |
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" device exists in the /sys/block tree" % path) |
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rdev = os.stat(path).st_rdev |
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if devnum != rdev: |
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raise SysconfigError("For device %s, the major:minor in /dev is %04x" |
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" while the major:minor in sysfs is %s" % |
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(path, rdev, devnum)) |
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|
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|
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def ReadDev(syspath): |
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"""Reads the device number from a sysfs path. |
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|
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The device number is given in sysfs under a block device directory |
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in a file named 'dev' which contains major:minor (in ASCII). This |
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function reads that file and converts the major:minor pair to a dev |
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number. |
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|
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@type syspath: string |
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@param syspath: the path to a block device dir in sysfs, |
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e.g. C{/sys/block/sda} |
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|
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@return: the device number |
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|
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""" |
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if not os.path.exists("%s/dev" % syspath): |
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raise ProgrammingError("Invalid path passed to ReadDev: %s" % syspath) |
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f = open("%s/dev" % syspath) |
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data = f.read().strip() |
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f.close() |
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major, minor = data.split(":", 1) |
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major = int(major) |
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minor = int(minor) |
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dev = os.makedev(major, minor) |
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return dev |
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|
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|
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def ReadSize(syspath): |
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"""Reads the size from a sysfs path. |
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|
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The size is given in sysfs under a block device directory in a file |
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named 'size' which contains the number of sectors (in ASCII). This |
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function reads that file and converts the number in sectors to the |
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size in bytes. |
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|
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@type syspath: string |
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@param syspath: the path to a block device dir in sysfs, |
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e.g. C{/sys/block/sda} |
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|
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@rtype: int |
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@return: the device size in bytes |
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|
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""" |
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|
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if not os.path.exists("%s/size" % syspath): |
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raise ProgrammingError("Invalid path passed to ReadSize: %s" % syspath) |
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f = open("%s/size" % syspath) |
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data = f.read().strip() |
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f.close() |
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size = 512L * int(data) |
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return size |
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|
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|
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def ReadPV(name): |
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"""Reads physical volume information. |
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|
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This function tries to see if a block device is a physical volume. |
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|
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@type name: string |
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@param name: the device name (e.g. sda) |
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|
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@return: the name of the volume group to which this PV belongs, or |
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"" if this PV is not in use, or None if this is not a PV |
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|
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""" |
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result = ExecCommand("pvdisplay -c /dev/%s" % name) |
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if result.failed: |
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return None |
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vgname = result.stdout.strip().split(":")[1] |
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return vgname |
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|
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|
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def GetDiskList(opts): |
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"""Computes the block device list for this system. |
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|
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This function examines the /sys/block tree and using information |
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therein, computes the status of the block device. |
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|
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@return: a list like [(name, size, dev, partitions, inuse), ...], where: |
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- name is the block device name (e.g. sda) |
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- size the size in bytes |
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- dev is the device number (e.g. 8704 for hdg) |
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- partitions is [(name, size, dev), ...] mirroring the disk list |
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data inuse is a boolean showing the in-use status of the disk, |
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computed as the possibility of re-reading the partition table |
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(the meaning of the operation varies with the kernel version, |
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but is usually accurate; a mounted disk/partition or swap-area |
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or PV with active LVs on it is busy) |
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|
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""" |
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dlist = [] |
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for name in os.listdir("/sys/block"): |
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if not compat.any([name.startswith(pfx) for pfx in SUPPORTED_TYPES]): |
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continue |
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|
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disksysfsname = "/sys/block/%s" % name |
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size = ReadSize(disksysfsname) |
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|
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f = open("/sys/block/%s/removable" % name) |
456 |
removable = int(f.read().strip()) |
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f.close() |
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|
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if removable and not opts.removable_ok: |
460 |
continue |
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|
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dev = ReadDev(disksysfsname) |
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CheckSysDev(name, dev) |
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inuse = InUse(name) |
465 |
# Enumerate partitions of the block device |
466 |
partitions = [] |
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for partname in os.listdir(disksysfsname): |
468 |
if not partname.startswith(name): |
469 |
continue |
470 |
partsysfsname = "%s/%s" % (disksysfsname, partname) |
471 |
partdev = ReadDev(partsysfsname) |
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partsize = ReadSize(partsysfsname) |
473 |
if partsize >= PART_MINSIZE: |
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CheckSysDev(partname, partdev) |
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partinuse = InUse(partname) |
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partitions.append((partname, partsize, partdev, partinuse)) |
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partitions.sort() |
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dlist.append((name, size, dev, partitions, inuse)) |
479 |
dlist.sort() |
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return dlist |
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|
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|
483 |
def GetMountInfo(): |
484 |
"""Reads /proc/mounts and computes the mountpoint-devnum mapping. |
485 |
|
486 |
This function reads /proc/mounts, finds the mounted filesystems |
487 |
(excepting a hard-coded blacklist of network and virtual |
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filesystems) and does a stat on these mountpoints. The st_dev number |
489 |
of the results is memorised for later matching against the |
490 |
/sys/block devices. |
491 |
|
492 |
@rtype: dict |
493 |
@return: a {mountpoint: device number} dictionary |
494 |
|
495 |
""" |
496 |
mountlines = ReadFile("/proc/mounts").splitlines() |
497 |
mounts = {} |
498 |
for line in mountlines: |
499 |
_, mountpoint, fstype, _ = line.split(None, 3) |
500 |
# fs type blacklist |
501 |
if fstype in EXCLUDED_FS: |
502 |
continue |
503 |
try: |
504 |
dev = os.stat(mountpoint).st_dev |
505 |
except OSError, err: |
506 |
# this should be a fairly rare error, since we are blacklisting |
507 |
# network filesystems; with this in mind, we'll ignore it, |
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# since the rereadpt check catches in-use filesystems, |
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# and this is used for disk information only |
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print >> sys.stderr, ("Can't stat mountpoint '%s': %s" % |
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(mountpoint, err)) |
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print >> sys.stderr, "Ignoring." |
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continue |
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mounts[dev] = mountpoint |
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return mounts |
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|
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|
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def GetSwapInfo(): |
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"""Reads /proc/swaps and returns the list of swap backing stores. |
520 |
|
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""" |
522 |
swaplines = ReadFile("/proc/swaps").splitlines()[1:] |
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return [line.split(None, 1)[0] for line in swaplines] |
524 |
|
525 |
|
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def DevInfo(name, dev, mountinfo): |
527 |
"""Computes miscellaneous information about a block device. |
528 |
|
529 |
@type name: string |
530 |
@param name: the device name, e.g. sda |
531 |
|
532 |
@return: a tuple (mpath, whatvg, fileinfo), where: |
533 |
- mpath is the mount path where this device is mounted or None |
534 |
- whatvg is the result of the ReadPV function |
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- fileinfo is the output of file -bs on the device |
536 |
|
537 |
""" |
538 |
if dev in mountinfo: |
539 |
mpath = mountinfo[dev] |
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else: |
541 |
mpath = None |
542 |
|
543 |
whatvg = ReadPV(name) |
544 |
|
545 |
result = ExecCommand("file -bs /dev/%s" % name) |
546 |
if result.failed: |
547 |
fileinfo = "<error: %s>" % result.stderr |
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fileinfo = result.stdout[:45] |
549 |
return mpath, whatvg, fileinfo |
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|
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|
552 |
def ShowDiskInfo(opts): |
553 |
"""Shows a nicely formatted block device list for this system. |
554 |
|
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This function shows the user a table with the information gathered |
556 |
by the other functions defined, in order to help the user make a |
557 |
choice about which disks should be allocated to our volume group. |
558 |
|
559 |
""" |
560 |
def _inuse(inuse): |
561 |
if inuse: |
562 |
return "yes" |
563 |
else: |
564 |
return "no" |
565 |
|
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mounts = GetMountInfo() |
567 |
dlist = GetDiskList(opts) |
568 |
|
569 |
print "------- Disk information -------" |
570 |
headers = { |
571 |
"name": "Name", |
572 |
"size": "Size[M]", |
573 |
"used": "Used", |
574 |
"mount": "Mount", |
575 |
"lvm": "LVM?", |
576 |
"info": "Info", |
577 |
} |
578 |
fields = ["name", "size", "used", "mount", "lvm", "info"] |
579 |
|
580 |
flatlist = [] |
581 |
# Flatten the [(disk, [partition,...]), ...] list |
582 |
for name, size, dev, parts, inuse in dlist: |
583 |
flatlist.append((name, size, dev, _inuse(inuse))) |
584 |
for partname, partsize, partdev, partinuse in parts: |
585 |
flatlist.append((partname, partsize, partdev, _inuse(partinuse))) |
586 |
|
587 |
strlist = [] |
588 |
for name, size, dev, in_use in flatlist: |
589 |
mp, vgname, fileinfo = DevInfo(name, dev, mounts) |
590 |
if mp is None: |
591 |
mp = "-" |
592 |
if vgname is None: |
593 |
lvminfo = "-" |
594 |
elif vgname == "": |
595 |
lvminfo = "yes,free" |
596 |
else: |
597 |
lvminfo = "in %s" % vgname |
598 |
|
599 |
if len(name) > 3: |
600 |
# Indent partitions |
601 |
name = " %s" % name |
602 |
|
603 |
strlist.append([name, "%.2f" % (float(size) / 1024 / 1024), |
604 |
in_use, mp, lvminfo, fileinfo]) |
605 |
|
606 |
data = cli.GenerateTable(headers, fields, None, |
607 |
strlist, numfields=["size"]) |
608 |
|
609 |
for line in data: |
610 |
print line |
611 |
|
612 |
|
613 |
def CheckSysfsHolders(name): |
614 |
"""Check to see if a device is 'hold' at sysfs level. |
615 |
|
616 |
This is usually the case for Physical Volumes under LVM. |
617 |
|
618 |
@rtype: boolean |
619 |
@return: true if the device is available according to sysfs |
620 |
|
621 |
""" |
622 |
try: |
623 |
contents = os.listdir("%s/holders/" % SysfsName(name)) |
624 |
except OSError, err: |
625 |
if err.errno == errno.ENOENT: |
626 |
contents = [] |
627 |
else: |
628 |
raise |
629 |
return not bool(contents) |
630 |
|
631 |
|
632 |
def CheckReread(name): |
633 |
"""Check to see if a block device is in use. |
634 |
|
635 |
Uses blockdev to reread the partition table of a block device (or |
636 |
fuser if the device is not partitionable), and thus compute the |
637 |
in-use status. See the discussion in GetDiskList about the meaning |
638 |
of 'in use'. |
639 |
|
640 |
@rtype: boolean |
641 |
@return: the in-use status of the device |
642 |
|
643 |
""" |
644 |
use_blockdev = IsPartitioned(name) |
645 |
if use_blockdev: |
646 |
cmd = "blockdev --rereadpt /dev/%s" % name |
647 |
else: |
648 |
cmd = "fuser -vam /dev/%s" % name |
649 |
|
650 |
for _ in range(3): |
651 |
result = ExecCommand(cmd) |
652 |
if not use_blockdev and result.failed: |
653 |
break |
654 |
elif use_blockdev and not result.failed: |
655 |
break |
656 |
time.sleep(2) |
657 |
|
658 |
if use_blockdev: |
659 |
return not result.failed |
660 |
else: |
661 |
return result.failed |
662 |
|
663 |
|
664 |
def CheckMounted(name): |
665 |
"""Check to see if a block device is a mountpoint. |
666 |
|
667 |
In recent distros/kernels, this is reported directly via fuser, but |
668 |
on older ones not, so we do an additional check here (manually). |
669 |
|
670 |
""" |
671 |
minfo = GetMountInfo() |
672 |
dev = ReadDev(SysfsName(name)) |
673 |
return dev not in minfo |
674 |
|
675 |
|
676 |
def CheckSwap(name): |
677 |
"""Check to see if a block device is being used as swap. |
678 |
|
679 |
""" |
680 |
name = "/dev/%s" % name |
681 |
return name not in GetSwapInfo() |
682 |
|
683 |
|
684 |
def InUse(name): |
685 |
"""Returns if a disk is in use or not. |
686 |
|
687 |
""" |
688 |
return not (CheckSysfsHolders(name) and CheckReread(name) and |
689 |
CheckMounted(name) and CheckSwap(name)) |
690 |
|
691 |
|
692 |
def WipeDisk(name): |
693 |
"""Wipes a block device. |
694 |
|
695 |
This function wipes a block device, by clearing and re-reading the |
696 |
partition table. If not successful, it writes back the old partition |
697 |
data, and leaves the cleanup to the user. |
698 |
|
699 |
@param name: the device name (e.g. sda) |
700 |
|
701 |
""" |
702 |
|
703 |
if InUse(name): |
704 |
raise OperationalError("CRITICAL: disk %s you selected seems to be in" |
705 |
" use. ABORTING!" % name) |
706 |
|
707 |
fd = os.open("/dev/%s" % name, os.O_RDWR | os.O_SYNC) |
708 |
olddata = os.read(fd, 512) |
709 |
if len(olddata) != 512: |
710 |
raise OperationalError("CRITICAL: Can't read partition table information" |
711 |
" from /dev/%s (needed 512 bytes, got %d" % |
712 |
(name, len(olddata))) |
713 |
newdata = "\0" * 512 |
714 |
os.lseek(fd, 0, 0) |
715 |
bytes_written = os.write(fd, newdata) |
716 |
os.close(fd) |
717 |
if bytes_written != 512: |
718 |
raise OperationalError("CRITICAL: Can't write partition table information" |
719 |
" to /dev/%s (tried to write 512 bytes, written" |
720 |
" %d. I don't know how to cleanup. Sorry." % |
721 |
(name, bytes_written)) |
722 |
|
723 |
if InUse(name): |
724 |
# try to restore the data |
725 |
fd = os.open("/dev/%s" % name, os.O_RDWR | os.O_SYNC) |
726 |
os.write(fd, olddata) |
727 |
os.close(fd) |
728 |
raise OperationalError("CRITICAL: disk %s which I have just wiped cannot" |
729 |
" reread partition table. Most likely, it is" |
730 |
" in use. You have to clean after this yourself." |
731 |
" I tried to restore the old partition table," |
732 |
" but I cannot guarantee nothing has broken." % |
733 |
name) |
734 |
|
735 |
|
736 |
def PartitionDisk(name, use_sfdisk): |
737 |
"""Partitions a disk. |
738 |
|
739 |
This function creates a single partition spanning the entire disk, |
740 |
by means of fdisk. |
741 |
|
742 |
@param name: the device name, e.g. sda |
743 |
|
744 |
""" |
745 |
|
746 |
# Check that parted exists |
747 |
result = ExecCommand("parted --help") |
748 |
if result.failed: |
749 |
use_sfdisk = True |
750 |
print >> sys.stderr, ("Unable to execute \"parted --help\"," |
751 |
" falling back to sfdisk.") |
752 |
|
753 |
# Check disk size - over 2TB means we need to use GPT |
754 |
size = ReadSize("/sys/block/%s" % name) |
755 |
if size > MBR_MAX_SIZE: |
756 |
label_type = "gpt" |
757 |
if use_sfdisk: |
758 |
raise OperationalError("Critical: Disk larger than 2TB detected, but" |
759 |
" parted is either not installed or --use-sfdisk" |
760 |
" has been specified") |
761 |
else: |
762 |
label_type = "msdos" |
763 |
|
764 |
if use_sfdisk: |
765 |
result = ExecCommand( |
766 |
"echo ,,8e, | sfdisk /dev/%s" % name) |
767 |
if result.failed: |
768 |
raise OperationalError("CRITICAL: disk %s which I have just partitioned" |
769 |
" cannot reread its partition table, or there" |
770 |
" is some other sfdisk error. Likely, it is in" |
771 |
" use. You have to clean this yourself. Error" |
772 |
" message from sfdisk: %s" % |
773 |
(name, result.output)) |
774 |
|
775 |
else: |
776 |
result = ExecCommand("parted -s /dev/%s mklabel %s" % (name, label_type)) |
777 |
if result.failed: |
778 |
raise OperationalError("Critical: failed to create %s label on %s" % |
779 |
(label_type, name)) |
780 |
result = ExecCommand("parted -s /dev/%s mkpart pri ext2 1 100%%" % name) |
781 |
if result.failed: |
782 |
raise OperationalError("Critical: failed to create partition on %s" % |
783 |
name) |
784 |
result = ExecCommand("parted -s /dev/%s set 1 lvm on" % name) |
785 |
if result.failed: |
786 |
raise OperationalError("Critical: failed to set partition on %s to LVM" % |
787 |
name) |
788 |
|
789 |
|
790 |
def CreatePVOnDisk(name): |
791 |
"""Creates a physical volume on a block device. |
792 |
|
793 |
This function creates a physical volume on a block device, overriding |
794 |
all warnings. So it can wipe existing PVs and PVs which are in a VG. |
795 |
|
796 |
@param name: the device name, e.g. sda |
797 |
|
798 |
""" |
799 |
device = DeviceName(name) |
800 |
result = ExecCommand("pvcreate -yff %s" % device) |
801 |
if result.failed: |
802 |
raise OperationalError("I cannot create a physical volume on" |
803 |
" %s. Error message: %s." |
804 |
" Please clean up yourself." % |
805 |
(device, result.output)) |
806 |
|
807 |
|
808 |
def CreateVG(vgname, disks): |
809 |
"""Creates the volume group. |
810 |
|
811 |
This function creates a volume group named `vgname` on the disks |
812 |
given as parameters. The physical extent size is set to 64MB. |
813 |
|
814 |
@param disks: a list of disk names, e.g. ['sda','sdb'] |
815 |
|
816 |
""" |
817 |
pnames = [DeviceName(d) for d in disks] |
818 |
result = ExecCommand("vgcreate -s 64MB '%s' %s" % (vgname, " ".join(pnames))) |
819 |
if result.failed: |
820 |
raise OperationalError("I cannot create the volume group %s from" |
821 |
" disks %s. Error message: %s. Please clean up" |
822 |
" yourself." % |
823 |
(vgname, " ".join(disks), result.output)) |
824 |
|
825 |
|
826 |
def ValidateDiskList(options): |
827 |
"""Validates or computes the disk list for create. |
828 |
|
829 |
This function either computes the available disk list (if the user |
830 |
gave --alldisks option), or validates the user-given disk list (by |
831 |
using the --disks option) such that all given disks are present and |
832 |
not in use. |
833 |
|
834 |
@param options: the options returned from OptParser.parse_options |
835 |
|
836 |
@return: a list of disk names, e.g. ['sda', 'sdb'] |
837 |
|
838 |
""" |
839 |
sysdisks = GetDiskList(options) |
840 |
if not sysdisks: |
841 |
raise PrereqError("no disks found (I looked for" |
842 |
" non-removable block devices).") |
843 |
sysd_free = [] |
844 |
sysd_used = [] |
845 |
for name, _, _, parts, used in sysdisks: |
846 |
if used: |
847 |
sysd_used.append(name) |
848 |
for partname, _, _, partused in parts: |
849 |
if partused: |
850 |
sysd_used.append(partname) |
851 |
else: |
852 |
sysd_free.append(partname) |
853 |
else: |
854 |
sysd_free.append(name) |
855 |
|
856 |
if not sysd_free: |
857 |
raise PrereqError("no free disks found! (%d in-use disks)" % |
858 |
len(sysd_used)) |
859 |
if options.alldisks: |
860 |
disklist = sysd_free |
861 |
elif options.disks: |
862 |
disklist = options.disks.split(",") |
863 |
for name in disklist: |
864 |
if name in sysd_used: |
865 |
raise ParameterError("disk %s is in use, cannot wipe!" % name) |
866 |
if name not in sysd_free: |
867 |
raise ParameterError("cannot find disk %s!" % name) |
868 |
else: |
869 |
raise ParameterError("Please use either --alldisks or --disks!") |
870 |
|
871 |
return disklist |
872 |
|
873 |
|
874 |
def BootStrap(): |
875 |
"""Actual main routine. |
876 |
|
877 |
""" |
878 |
CheckPrereq() |
879 |
|
880 |
options, args = ParseOptions() |
881 |
vgname = options.vgname |
882 |
command = args.pop(0) |
883 |
if command == "diskinfo": |
884 |
ShowDiskInfo(options) |
885 |
return |
886 |
if command != "create": |
887 |
Usage() |
888 |
|
889 |
exists, lv_count, vg_size, vg_free = CheckVGExists(vgname) |
890 |
if exists: |
891 |
raise PrereqError("It seems volume group '%s' already exists:\n" |
892 |
" LV count: %s, size: %s, free: %s." % |
893 |
(vgname, lv_count, vg_size, vg_free)) |
894 |
|
895 |
disklist = ValidateDiskList(options) |
896 |
|
897 |
for disk in disklist: |
898 |
WipeDisk(disk) |
899 |
if IsPartitioned(disk): |
900 |
PartitionDisk(disk, options.use_sfdisk) |
901 |
for disk in disklist: |
902 |
CreatePVOnDisk(disk) |
903 |
CreateVG(vgname, disklist) |
904 |
|
905 |
status, lv_count, size, _ = CheckVGExists(vgname) |
906 |
if status: |
907 |
print "Done! %s: size %s GiB, disks: %s" % (vgname, size, |
908 |
",".join(disklist)) |
909 |
else: |
910 |
raise OperationalError("Although everything seemed ok, the volume" |
911 |
" group did not get created.") |
912 |
|
913 |
|
914 |
def main(): |
915 |
"""Application entry point. |
916 |
|
917 |
This is just a wrapper over BootStrap, to handle our own exceptions. |
918 |
|
919 |
""" |
920 |
try: |
921 |
BootStrap() |
922 |
except PrereqError, err: |
923 |
print >> sys.stderr, "The prerequisites for running this tool are not met." |
924 |
print >> sys.stderr, ("Please make sure you followed all the steps in" |
925 |
" the build document.") |
926 |
print >> sys.stderr, "Description: %s" % str(err) |
927 |
sys.exit(1) |
928 |
except SysconfigError, err: |
929 |
print >> sys.stderr, ("This system's configuration seems wrong, at" |
930 |
" least is not what I expect.") |
931 |
print >> sys.stderr, ("Please check that the installation didn't fail" |
932 |
" at some step.") |
933 |
print >> sys.stderr, "Description: %s" % str(err) |
934 |
sys.exit(1) |
935 |
except ParameterError, err: |
936 |
print >> sys.stderr, ("Some parameters you gave to the program or the" |
937 |
" invocation is wrong. ") |
938 |
print >> sys.stderr, "Description: %s" % str(err) |
939 |
Usage() |
940 |
except OperationalError, err: |
941 |
print >> sys.stderr, ("A serious error has happened while modifying" |
942 |
" the system's configuration.") |
943 |
print >> sys.stderr, ("Please review the error message below and make" |
944 |
" sure you clean up yourself.") |
945 |
print >> sys.stderr, ("It is most likely that the system configuration" |
946 |
" has been partially altered.") |
947 |
print >> sys.stderr, str(err) |
948 |
sys.exit(1) |
949 |
except ProgrammingError, err: |
950 |
print >> sys.stderr, ("Internal application error. Please report this" |
951 |
" to the Ganeti developer list.") |
952 |
print >> sys.stderr, "Error description: %s" % str(err) |
953 |
sys.exit(1) |
954 |
except Error, err: |
955 |
print >> sys.stderr, "Unhandled application error: %s" % err |
956 |
sys.exit(1) |
957 |
except (IOError, OSError), err: |
958 |
print >> sys.stderr, "I/O error detected, please report." |
959 |
print >> sys.stderr, "Description: %s" % str(err) |
960 |
sys.exit(1) |
961 |
|
962 |
|
963 |
if __name__ == "__main__": |
964 |
main() |