1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
|
#!/usr/bin/python3
"""
Copyright (C) 2023 Michael Ablassmeier <abi@grinser.de>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
"""
import os
import sys
import tempfile
import signal
import time
import argparse
import logging
from functools import partial
from libvirtnbdbackup import argopt
from libvirtnbdbackup import __version__
from libvirtnbdbackup import sighandle
from libvirtnbdbackup.map import changes
from libvirtnbdbackup.map import ranges
from libvirtnbdbackup.map import requirements
from libvirtnbdbackup.qemu import util as qemu
from libvirtnbdbackup.qemu.exceptions import ProcessError, QemuHelperError
from libvirtnbdbackup.exceptions import RestoreError
from libvirtnbdbackup.output.exceptions import OutputException
from libvirtnbdbackup import common as lib
from libvirtnbdbackup.logcount import logCount
from libvirtnbdbackup.sparsestream import streamer
from libvirtnbdbackup.sparsestream import types
# pylint: disable=unreachable
def main() -> None:
"""Map full backup file to nbd device for single file or
instant recovery"""
parser = argparse.ArgumentParser(
description="Map backup image(s) to block device",
epilog=(
"Examples:\n"
" # Map full backup to device /dev/nbd0:\n"
"\t%(prog)s -f /backup/sda.full.data\n"
" # Map full backup to device /dev/nbd2:\n"
"\t%(prog)s -f /backup/sda.full.data -d /dev/nbd2\n"
" # Map sequence of full and incremental to device /dev/nbd2:\n"
"\t%(prog)s -f /backup/sda.full.data,/backup/sda.inc.1.data -d /dev/nbd2\n"
),
formatter_class=argparse.RawTextHelpFormatter,
)
opt = parser.add_argument_group("General options")
opt.add_argument(
"-f", "--file", required=True, type=str, help="List of Backup files to map"
)
opt.add_argument(
"-b",
"--blocksize",
required=False,
type=str,
default="4096",
help="Maximum blocksize passed to nbdkit. (default: %(default)s)",
)
opt.add_argument(
"-d",
"--device",
default="/dev/nbd0",
type=str,
help="Target device. (default: %(default)s)",
)
opt.add_argument(
"-e",
"--export-name",
default="sda",
type=str,
help="Export name passed to nbdkit. (default: %(default)s)",
)
opt.add_argument(
"-t",
"--threads",
default=1,
type=str,
help="Amount of threads passed to nbdkit process. (default: %(default)s)",
)
opt.add_argument(
"-l",
"--listen-address",
default="127.0.0.1",
type=str,
help="IP Address for nbdkit process to listen on. (default: %(default)s)",
)
opt.add_argument(
"-p",
"--listen-port",
default="10809",
type=str,
help="Port for nbdkit process to listen on. (default: %(default)s)",
)
opt.add_argument(
"-n",
"--noprogress",
required=False,
action="store_true",
default=False,
help="Disable progress bar",
)
logopt = parser.add_argument_group("Logging options")
argopt.addLogArgs(logopt, parser.prog)
argopt.addLogColorArgs(logopt)
debopt = parser.add_argument_group("Debug options")
debopt.add_argument(
"-r",
"--readonly",
required=False,
action="store_true",
help="Map image readonly (default: %(default)s)",
)
debopt.add_argument(
"-H",
"--hexdump",
required=False,
action="store_true",
help="Hexdump data to logfile for debugging (default: %(default)s)",
)
argopt.addDebugArgs(debopt)
args = lib.argparse(parser)
args.sshClient = None
args.quiet = False
fileLog = lib.getLogFile(args.logfile) or sys.exit(1)
lib.setThreadName()
counter = logCount()
lib.configLogger(args, fileLog, counter)
lib.printVersion(__version__)
nbdkitModule = requirements.plugin(args)
logging.info("Logfile: [%s]", args.logfile)
logging.info("Plugin location: [%s]", nbdkitModule)
requirements.executables()
requirements.device(args)
dataFiles = args.file.split(",")
if len(dataFiles) > 1 and not "full.data" in dataFiles[0]:
logging.error("Sequence must start with a full backup")
if len(dataFiles) > 1 and args.readonly:
logging.error("Device mapping with incrementals doesn't work in readonly mode")
if counter.count.errors > 0:
sys.exit(1)
fullImage = os.path.abspath(dataFiles[0])
stream = streamer.SparseStream(types)
sTypes = types.SparseStreamTypes()
# pylint: disable=consider-using-with
blockMap = tempfile.NamedTemporaryFile(delete=False, prefix="block.", suffix=".map")
logging.info("Write blockmap to temporary file: [%s]", blockMap.name)
try:
dataRanges = ranges.get(args, stream, sTypes, dataFiles)
except RestoreError as e:
logging.error(e)
sys.exit(1)
if not ranges.dump(blockMap, dataRanges):
sys.exit(1)
blockMap.flush()
blockMap.close()
logging.info("Target device: %s", args.device)
qFh = qemu.util(args.export_name)
try:
nbdkitProcess = qFh.startNbdkitProcess(
args, nbdkitModule, blockMap.name, fullImage
)
except QemuHelperError as e:
logging.error("Failed to start nbdkit process: [%s]", e)
sys.exit(1)
logging.info(
"Started nbdkit process pid: [%s], Logfile: [%s]",
nbdkitProcess.pid,
nbdkitProcess.logFile,
)
signal.signal(
signal.SIGINT,
partial(sighandle.Map.catch, args, nbdkitProcess, blockMap, logging),
)
maxRetry = 10
retryCnt = 0
nbdCmd = [
"qemu-nbd",
"-c",
f"{args.device}",
f"nbd://{args.listen_address}:{args.listen_port}/{args.export_name}",
"-f",
"raw",
]
if args.readonly:
logging.warning("Device will be mapped readonly without cow.")
logging.warning("Mounting will only work with '-o norecovery,ro'")
nbdCmd.append("-r")
logging.debug(nbdCmd)
while True:
try:
qemu.command.run(cmdLine=nbdCmd, toPipe=True)
break
except ProcessError as e:
if retryCnt >= maxRetry:
logging.info("Unable to connect device after service start: %s", e)
lib.killProc(nbdkitProcess.pid)
break
if "Connection refused" in str(e):
logging.info("NBD server refused connection, retry [%s]", retryCnt)
time.sleep(1)
retryCnt += 1
else:
logging.error("Failed to map device:")
logging.error("Stderr: [%s]", str(e))
lib.killProc(nbdkitProcess.pid)
if len(dataFiles) > 1:
try:
changes.replay(dataRanges, args)
except OutputException as e:
logging.error("Failed to replay changes: %s", e)
qemu.util("").disconnect(args.device)
lib.killProc(nbdkitProcess.pid)
sys.exit(1)
logging.info("Done mapping backup image to [%s]", args.device)
logging.info("Press CTRL+C to disconnect")
while True:
time.sleep(60)
if __name__ == "__main__":
main()
|
