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19 package org.apache.hadoop.hbase.snapshot;
20
21 import java.io.FileNotFoundException;
22 import java.io.IOException;
23 import java.util.ArrayList;
24 import java.util.Collections;
25 import java.util.Comparator;
26 import java.util.LinkedList;
27 import java.util.List;
28
29 import org.apache.commons.logging.Log;
30 import org.apache.commons.logging.LogFactory;
31
32 import org.apache.hadoop.classification.InterfaceAudience;
33 import org.apache.hadoop.classification.InterfaceStability;
34 import org.apache.hadoop.conf.Configuration;
35 import org.apache.hadoop.conf.Configured;
36 import org.apache.hadoop.fs.FSDataInputStream;
37 import org.apache.hadoop.fs.FSDataOutputStream;
38 import org.apache.hadoop.fs.FileChecksum;
39 import org.apache.hadoop.fs.FileStatus;
40 import org.apache.hadoop.fs.FileSystem;
41 import org.apache.hadoop.fs.FileUtil;
42 import org.apache.hadoop.fs.Path;
43 import org.apache.hadoop.fs.permission.FsPermission;
44 import org.apache.hadoop.hbase.HBaseConfiguration;
45 import org.apache.hadoop.hbase.HConstants;
46 import org.apache.hadoop.hbase.io.HFileLink;
47 import org.apache.hadoop.hbase.io.HLogLink;
48 import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription;
49 import org.apache.hadoop.hbase.regionserver.StoreFile;
50 import org.apache.hadoop.hbase.snapshot.ExportSnapshotException;
51 import org.apache.hadoop.hbase.snapshot.SnapshotDescriptionUtils;
52 import org.apache.hadoop.hbase.snapshot.SnapshotReferenceUtil;
53 import org.apache.hadoop.hbase.util.Bytes;
54 import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
55 import org.apache.hadoop.hbase.util.FSUtils;
56 import org.apache.hadoop.hbase.util.Pair;
57 import org.apache.hadoop.io.NullWritable;
58 import org.apache.hadoop.io.SequenceFile;
59 import org.apache.hadoop.io.Text;
60 import org.apache.hadoop.mapreduce.Job;
61 import org.apache.hadoop.mapreduce.Mapper;
62 import org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFormat;
63 import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;
64 import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
65 import org.apache.hadoop.mapreduce.lib.output.NullOutputFormat;
66 import org.apache.hadoop.util.StringUtils;
67 import org.apache.hadoop.util.Tool;
68 import org.apache.hadoop.util.ToolRunner;
69
70
71
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73
74
75
76
77 @InterfaceAudience.Public
78 @InterfaceStability.Evolving
79 public final class ExportSnapshot extends Configured implements Tool {
80 private static final Log LOG = LogFactory.getLog(ExportSnapshot.class);
81
82 private static final String CONF_FILES_USER = "snapshot.export.files.attributes.user";
83 private static final String CONF_FILES_GROUP = "snapshot.export.files.attributes.group";
84 private static final String CONF_FILES_MODE = "snapshot.export.files.attributes.mode";
85 private static final String CONF_CHECKSUM_VERIFY = "snapshot.export.checksum.verify";
86 private static final String CONF_OUTPUT_ROOT = "snapshot.export.output.root";
87 private static final String CONF_INPUT_ROOT = "snapshot.export.input.root";
88 private static final String CONF_STAGING_ROOT = "snapshot.export.staging.root";
89
90 private static final String INPUT_FOLDER_PREFIX = "export-files.";
91
92
93 public enum Counter { MISSING_FILES, COPY_FAILED, BYTES_EXPECTED, BYTES_COPIED };
94
95 private static class ExportMapper extends Mapper<Text, NullWritable, NullWritable, NullWritable> {
96 final static int REPORT_SIZE = 1 * 1024 * 1024;
97 final static int BUFFER_SIZE = 64 * 1024;
98
99 private boolean verifyChecksum;
100 private String filesGroup;
101 private String filesUser;
102 private short filesMode;
103
104 private FileSystem outputFs;
105 private Path outputArchive;
106 private Path outputRoot;
107
108 private FileSystem inputFs;
109 private Path inputArchive;
110 private Path inputRoot;
111
112 @Override
113 public void setup(Context context) {
114 Configuration conf = context.getConfiguration();
115 verifyChecksum = conf.getBoolean(CONF_CHECKSUM_VERIFY, true);
116
117 filesGroup = conf.get(CONF_FILES_GROUP);
118 filesUser = conf.get(CONF_FILES_USER);
119 filesMode = (short)conf.getInt(CONF_FILES_MODE, 0);
120 outputRoot = new Path(conf.get(CONF_OUTPUT_ROOT));
121 inputRoot = new Path(conf.get(CONF_INPUT_ROOT));
122
123 inputArchive = new Path(inputRoot, HConstants.HFILE_ARCHIVE_DIRECTORY);
124 outputArchive = new Path(outputRoot, HConstants.HFILE_ARCHIVE_DIRECTORY);
125
126 try {
127 inputFs = FileSystem.get(inputRoot.toUri(), conf);
128 } catch (IOException e) {
129 throw new RuntimeException("Could not get the input FileSystem with root=" + inputRoot, e);
130 }
131
132 try {
133 outputFs = FileSystem.get(outputRoot.toUri(), conf);
134 } catch (IOException e) {
135 throw new RuntimeException("Could not get the output FileSystem with root="+ outputRoot, e);
136 }
137 }
138
139 @Override
140 public void map(Text key, NullWritable value, Context context)
141 throws InterruptedException, IOException {
142 Path inputPath = new Path(key.toString());
143 Path outputPath = getOutputPath(inputPath);
144
145 LOG.info("copy file input=" + inputPath + " output=" + outputPath);
146 if (copyFile(context, inputPath, outputPath)) {
147 LOG.info("copy completed for input=" + inputPath + " output=" + outputPath);
148 }
149 }
150
151
152
153
154
155
156 private Path getOutputPath(final Path inputPath) throws IOException {
157 Path path;
158 if (HFileLink.isHFileLink(inputPath) || StoreFile.isReference(inputPath)) {
159 String family = inputPath.getParent().getName();
160 String table = HFileLink.getReferencedTableName(inputPath.getName());
161 String region = HFileLink.getReferencedRegionName(inputPath.getName());
162 String hfile = HFileLink.getReferencedHFileName(inputPath.getName());
163 path = new Path(table, new Path(region, new Path(family, hfile)));
164 } else if (isHLogLinkPath(inputPath)) {
165 String logName = inputPath.getName();
166 path = new Path(new Path(outputRoot, HConstants.HREGION_OLDLOGDIR_NAME), logName);
167 } else {
168 path = inputPath;
169 }
170 return new Path(outputArchive, path);
171 }
172
173 private boolean copyFile(final Context context, final Path inputPath, final Path outputPath)
174 throws IOException {
175 FSDataInputStream in = openSourceFile(inputPath);
176 if (in == null) {
177 context.getCounter(Counter.MISSING_FILES).increment(1);
178 return false;
179 }
180
181 try {
182
183 FileStatus inputStat = getFileStatus(inputFs, inputPath);
184 if (inputStat == null) return false;
185
186
187 if (outputFs.exists(outputPath)) {
188 FileStatus outputStat = outputFs.getFileStatus(outputPath);
189 if (sameFile(inputStat, outputStat)) {
190 LOG.info("Skip copy " + inputPath + " to " + outputPath + ", same file.");
191 return true;
192 }
193 }
194
195 context.getCounter(Counter.BYTES_EXPECTED).increment(inputStat.getLen());
196
197
198 outputFs.mkdirs(outputPath.getParent());
199 FSDataOutputStream out = outputFs.create(outputPath, true);
200 try {
201 if (!copyData(context, inputPath, in, outputPath, out, inputStat.getLen()))
202 return false;
203 } finally {
204 out.close();
205 }
206
207
208 return preserveAttributes(outputPath, inputStat);
209 } finally {
210 in.close();
211 }
212 }
213
214
215
216
217 private boolean preserveAttributes(final Path path, final FileStatus refStat) {
218 FileStatus stat;
219 try {
220 stat = outputFs.getFileStatus(path);
221 } catch (IOException e) {
222 LOG.warn("Unable to get the status for file=" + path);
223 return false;
224 }
225
226 try {
227 if (filesMode > 0 && stat.getPermission().toShort() != filesMode) {
228 outputFs.setPermission(path, new FsPermission(filesMode));
229 } else if (!stat.getPermission().equals(refStat.getPermission())) {
230 outputFs.setPermission(path, refStat.getPermission());
231 }
232 } catch (IOException e) {
233 LOG.error("Unable to set the permission for file=" + path, e);
234 return false;
235 }
236
237 try {
238 String user = (filesUser != null) ? filesUser : refStat.getOwner();
239 String group = (filesGroup != null) ? filesGroup : refStat.getGroup();
240 if (!(user.equals(stat.getOwner()) && group.equals(stat.getGroup()))) {
241 outputFs.setOwner(path, user, group);
242 }
243 } catch (IOException e) {
244 LOG.error("Unable to set the owner/group for file=" + path, e);
245 return false;
246 }
247
248 return true;
249 }
250
251 private boolean copyData(final Context context,
252 final Path inputPath, final FSDataInputStream in,
253 final Path outputPath, final FSDataOutputStream out,
254 final long inputFileSize) {
255 final String statusMessage = "copied %s/" + StringUtils.humanReadableInt(inputFileSize) +
256 " (%.3f%%)";
257
258 try {
259 byte[] buffer = new byte[BUFFER_SIZE];
260 long totalBytesWritten = 0;
261 int reportBytes = 0;
262 int bytesRead;
263
264 while ((bytesRead = in.read(buffer)) > 0) {
265 out.write(buffer, 0, bytesRead);
266 totalBytesWritten += bytesRead;
267 reportBytes += bytesRead;
268
269 if (reportBytes >= REPORT_SIZE) {
270 context.getCounter(Counter.BYTES_COPIED).increment(reportBytes);
271 context.setStatus(String.format(statusMessage,
272 StringUtils.humanReadableInt(totalBytesWritten),
273 totalBytesWritten/(float)inputFileSize) +
274 " from " + inputPath + " to " + outputPath);
275 reportBytes = 0;
276 }
277 }
278
279 context.getCounter(Counter.BYTES_COPIED).increment(reportBytes);
280 context.setStatus(String.format(statusMessage,
281 StringUtils.humanReadableInt(totalBytesWritten),
282 totalBytesWritten/(float)inputFileSize) +
283 " from " + inputPath + " to " + outputPath);
284
285
286 if (totalBytesWritten != inputFileSize) {
287 LOG.error("number of bytes copied not matching copied=" + totalBytesWritten +
288 " expected=" + inputFileSize + " for file=" + inputPath);
289 context.getCounter(Counter.COPY_FAILED).increment(1);
290 return false;
291 }
292
293 return true;
294 } catch (IOException e) {
295 LOG.error("Error copying " + inputPath + " to " + outputPath, e);
296 context.getCounter(Counter.COPY_FAILED).increment(1);
297 return false;
298 }
299 }
300
301 private FSDataInputStream openSourceFile(final Path path) {
302 try {
303 if (HFileLink.isHFileLink(path) || StoreFile.isReference(path)) {
304 return new HFileLink(inputRoot, inputArchive, path).open(inputFs);
305 } else if (isHLogLinkPath(path)) {
306 String serverName = path.getParent().getName();
307 String logName = path.getName();
308 return new HLogLink(inputRoot, serverName, logName).open(inputFs);
309 }
310 return inputFs.open(path);
311 } catch (IOException e) {
312 LOG.error("Unable to open source file=" + path, e);
313 return null;
314 }
315 }
316
317 private FileStatus getFileStatus(final FileSystem fs, final Path path) {
318 try {
319 if (HFileLink.isHFileLink(path) || StoreFile.isReference(path)) {
320 HFileLink link = new HFileLink(inputRoot, inputArchive, path);
321 return link.getFileStatus(fs);
322 } else if (isHLogLinkPath(path)) {
323 String serverName = path.getParent().getName();
324 String logName = path.getName();
325 return new HLogLink(inputRoot, serverName, logName).getFileStatus(fs);
326 }
327 return fs.getFileStatus(path);
328 } catch (IOException e) {
329 LOG.warn("Unable to get the status for file=" + path);
330 return null;
331 }
332 }
333
334 private FileChecksum getFileChecksum(final FileSystem fs, final Path path) {
335 try {
336 return fs.getFileChecksum(path);
337 } catch (IOException e) {
338 LOG.warn("Unable to get checksum for file=" + path, e);
339 return null;
340 }
341 }
342
343
344
345
346
347 private boolean sameFile(final FileStatus inputStat, final FileStatus outputStat) {
348
349 if (inputStat.getLen() != outputStat.getLen()) return false;
350
351
352 if (!verifyChecksum) return true;
353
354
355 FileChecksum inChecksum = getFileChecksum(inputFs, inputStat.getPath());
356 if (inChecksum == null) return false;
357
358 FileChecksum outChecksum = getFileChecksum(outputFs, outputStat.getPath());
359 if (outChecksum == null) return false;
360
361 return inChecksum.equals(outChecksum);
362 }
363
364
365
366
367
368
369 private static boolean isHLogLinkPath(final Path path) {
370 return path.depth() == 2;
371 }
372 }
373
374
375
376
377
378 private List<Pair<Path, Long>> getSnapshotFiles(final FileSystem fs, final Path snapshotDir)
379 throws IOException {
380 SnapshotDescription snapshotDesc = SnapshotDescriptionUtils.readSnapshotInfo(fs, snapshotDir);
381
382 final List<Pair<Path, Long>> files = new ArrayList<Pair<Path, Long>>();
383 final String table = snapshotDesc.getTable();
384 final Configuration conf = getConf();
385
386
387 SnapshotReferenceUtil.visitReferencedFiles(fs, snapshotDir,
388 new SnapshotReferenceUtil.FileVisitor() {
389 public void storeFile (final String region, final String family, final String hfile)
390 throws IOException {
391 Path path = HFileLink.createPath(table, region, family, hfile);
392 long size = new HFileLink(conf, path).getFileStatus(fs).getLen();
393 files.add(new Pair<Path, Long>(path, size));
394 }
395
396 public void recoveredEdits (final String region, final String logfile)
397 throws IOException {
398
399 }
400
401 public void logFile (final String server, final String logfile)
402 throws IOException {
403 long size = new HLogLink(conf, server, logfile).getFileStatus(fs).getLen();
404 files.add(new Pair<Path, Long>(new Path(server, logfile), size));
405 }
406 });
407
408 return files;
409 }
410
411
412
413
414
415
416
417
418
419 static List<List<Path>> getBalancedSplits(final List<Pair<Path, Long>> files, int ngroups) {
420
421 Collections.sort(files, new Comparator<Pair<Path, Long>>() {
422 public int compare(Pair<Path, Long> a, Pair<Path, Long> b) {
423 long r = a.getSecond() - b.getSecond();
424 return (r < 0) ? -1 : ((r > 0) ? 1 : 0);
425 }
426 });
427
428
429 List<List<Path>> fileGroups = new LinkedList<List<Path>>();
430 long[] sizeGroups = new long[ngroups];
431 int hi = files.size() - 1;
432 int lo = 0;
433
434 List<Path> group;
435 int dir = 1;
436 int g = 0;
437
438 while (hi >= lo) {
439 if (g == fileGroups.size()) {
440 group = new LinkedList<Path>();
441 fileGroups.add(group);
442 } else {
443 group = fileGroups.get(g);
444 }
445
446 Pair<Path, Long> fileInfo = files.get(hi--);
447
448
449 sizeGroups[g] += fileInfo.getSecond();
450 group.add(fileInfo.getFirst());
451
452
453 g += dir;
454 if (g == ngroups) {
455 dir = -1;
456 g = ngroups - 1;
457 } else if (g < 0) {
458 dir = 1;
459 g = 0;
460 }
461 }
462
463 if (LOG.isDebugEnabled()) {
464 for (int i = 0; i < sizeGroups.length; ++i) {
465 LOG.debug("export split=" + i + " size=" + StringUtils.humanReadableInt(sizeGroups[i]));
466 }
467 }
468
469 return fileGroups;
470 }
471
472 private static Path getInputFolderPath(final FileSystem fs, final Configuration conf)
473 throws IOException, InterruptedException {
474 String stagingName = "exportSnapshot-" + EnvironmentEdgeManager.currentTimeMillis();
475 Path stagingDir = new Path(conf.get(CONF_STAGING_ROOT, fs.getWorkingDirectory().toString())
476 , stagingName);
477 fs.mkdirs(stagingDir);
478 return new Path(stagingDir, INPUT_FOLDER_PREFIX +
479 String.valueOf(EnvironmentEdgeManager.currentTimeMillis()));
480 }
481
482
483
484
485
486
487
488 private static Path[] createInputFiles(final Configuration conf,
489 final List<Pair<Path, Long>> snapshotFiles, int mappers)
490 throws IOException, InterruptedException {
491 FileSystem fs = FileSystem.get(conf);
492 Path inputFolderPath = getInputFolderPath(fs, conf);
493 LOG.debug("Input folder location: " + inputFolderPath);
494
495 List<List<Path>> splits = getBalancedSplits(snapshotFiles, mappers);
496 Path[] inputFiles = new Path[splits.size()];
497
498 Text key = new Text();
499 for (int i = 0; i < inputFiles.length; i++) {
500 List<Path> files = splits.get(i);
501 inputFiles[i] = new Path(inputFolderPath, String.format("export-%d.seq", i));
502 SequenceFile.Writer writer = SequenceFile.createWriter(fs, conf, inputFiles[i],
503 Text.class, NullWritable.class);
504 LOG.debug("Input split: " + i);
505 try {
506 for (Path file: files) {
507 LOG.debug(file.toString());
508 key.set(file.toString());
509 writer.append(key, NullWritable.get());
510 }
511 } finally {
512 writer.close();
513 }
514 }
515
516 return inputFiles;
517 }
518
519
520
521
522 private boolean runCopyJob(final Path inputRoot, final Path outputRoot,
523 final List<Pair<Path, Long>> snapshotFiles, final boolean verifyChecksum,
524 final String filesUser, final String filesGroup, final int filesMode,
525 final int mappers) throws IOException, InterruptedException, ClassNotFoundException {
526 Configuration conf = getConf();
527 if (filesGroup != null) conf.set(CONF_FILES_GROUP, filesGroup);
528 if (filesUser != null) conf.set(CONF_FILES_USER, filesUser);
529 conf.setInt(CONF_FILES_MODE, filesMode);
530 conf.setBoolean(CONF_CHECKSUM_VERIFY, verifyChecksum);
531 conf.set(CONF_OUTPUT_ROOT, outputRoot.toString());
532 conf.set(CONF_INPUT_ROOT, inputRoot.toString());
533 conf.setInt("mapreduce.job.maps", mappers);
534
535
536 conf.setBoolean("mapreduce.map.speculative", false);
537 conf.setBoolean("mapreduce.reduce.speculative", false);
538 conf.setBoolean("mapred.map.tasks.speculative.execution", false);
539 conf.setBoolean("mapred.reduce.tasks.speculative.execution", false);
540
541 Job job = new Job(conf);
542 job.setJobName("ExportSnapshot");
543 job.setJarByClass(ExportSnapshot.class);
544 job.setMapperClass(ExportMapper.class);
545 job.setInputFormatClass(SequenceFileInputFormat.class);
546 job.setOutputFormatClass(NullOutputFormat.class);
547 job.setNumReduceTasks(0);
548 for (Path path: createInputFiles(conf, snapshotFiles, mappers)) {
549 LOG.debug("Add Input Path=" + path);
550 SequenceFileInputFormat.addInputPath(job, path);
551 }
552
553 return job.waitForCompletion(true);
554 }
555
556
557
558
559
560 @Override
561 public int run(String[] args) throws Exception {
562 boolean verifyChecksum = true;
563 String snapshotName = null;
564 String filesGroup = null;
565 String filesUser = null;
566 Path outputRoot = null;
567 int filesMode = 0;
568 int mappers = getConf().getInt("mapreduce.job.maps", 1);
569
570
571 for (int i = 0; i < args.length; i++) {
572 String cmd = args[i];
573 try {
574 if (cmd.equals("-snapshot")) {
575 snapshotName = args[++i];
576 } else if (cmd.equals("-copy-to")) {
577 outputRoot = new Path(args[++i]);
578 } else if (cmd.equals("-no-checksum-verify")) {
579 verifyChecksum = false;
580 } else if (cmd.equals("-mappers")) {
581 mappers = Integer.parseInt(args[++i]);
582 } else if (cmd.equals("-chuser")) {
583 filesUser = args[++i];
584 } else if (cmd.equals("-chgroup")) {
585 filesGroup = args[++i];
586 } else if (cmd.equals("-chmod")) {
587 filesMode = Integer.parseInt(args[++i], 8);
588 } else if (cmd.equals("-h") || cmd.equals("--help")) {
589 printUsageAndExit();
590 } else {
591 System.err.println("UNEXPECTED: " + cmd);
592 printUsageAndExit();
593 }
594 } catch (Exception e) {
595 printUsageAndExit();
596 }
597 }
598
599
600 if (snapshotName == null) {
601 System.err.println("Snapshot name not provided.");
602 printUsageAndExit();
603 }
604
605 if (outputRoot == null) {
606 System.err.println("Destination file-system not provided.");
607 printUsageAndExit();
608 }
609
610 Configuration conf = getConf();
611 Path inputRoot = FSUtils.getRootDir(conf);
612 FileSystem inputFs = FileSystem.get(conf);
613 FileSystem outputFs = FileSystem.get(outputRoot.toUri(), conf);
614
615 Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshotName, inputRoot);
616 Path snapshotTmpDir = SnapshotDescriptionUtils.getWorkingSnapshotDir(snapshotName, outputRoot);
617 Path outputSnapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshotName, outputRoot);
618
619
620 if (outputFs.exists(outputSnapshotDir)) {
621 System.err.println("The snapshot '" + snapshotName +
622 "' already exists in the destination: " + outputSnapshotDir);
623 return 1;
624 }
625
626
627 if (outputFs.exists(snapshotTmpDir)) {
628 System.err.println("A snapshot with the same name '" + snapshotName + "' may be in-progress");
629 System.err.println("Please check " + snapshotTmpDir + ". If the snapshot has completed, ");
630 System.err.println("consider removing " + snapshotTmpDir + " before retrying export");
631 return 1;
632 }
633
634
635 final List<Pair<Path, Long>> files = getSnapshotFiles(inputFs, snapshotDir);
636
637
638
639
640 try {
641 FileUtil.copy(inputFs, snapshotDir, outputFs, snapshotTmpDir, false, false, conf);
642 } catch (IOException e) {
643 System.err.println("Failed to copy the snapshot directory: from=" + snapshotDir +
644 " to=" + snapshotTmpDir);
645 e.printStackTrace(System.err);
646 return 1;
647 }
648
649
650
651
652 try {
653 if (files.size() == 0) {
654 LOG.warn("There are 0 store file to be copied. There may be no data in the table.");
655 } else {
656 if (!runCopyJob(inputRoot, outputRoot, files, verifyChecksum,
657 filesUser, filesGroup, filesMode, mappers)) {
658 throw new ExportSnapshotException("Snapshot export failed!");
659 }
660 }
661
662
663 if (!outputFs.rename(snapshotTmpDir, outputSnapshotDir)) {
664 System.err.println("Snapshot export failed!");
665 System.err.println("Unable to rename snapshot directory from=" +
666 snapshotTmpDir + " to=" + outputSnapshotDir);
667 return 1;
668 }
669
670 return 0;
671 } catch (Exception e) {
672 System.err.println("Snapshot export failed!");
673 e.printStackTrace(System.err);
674 outputFs.delete(outputSnapshotDir, true);
675 return 1;
676 }
677 }
678
679
680 private void printUsageAndExit() {
681 System.err.printf("Usage: bin/hbase %s [options]%n", getClass().getName());
682 System.err.println(" where [options] are:");
683 System.err.println(" -h|-help Show this help and exit.");
684 System.err.println(" -snapshot NAME Snapshot to restore.");
685 System.err.println(" -copy-to NAME Remote destination hdfs://");
686 System.err.println(" -no-checksum-verify Do not verify checksum.");
687 System.err.println(" -chuser USERNAME Change the owner of the files to the specified one.");
688 System.err.println(" -chgroup GROUP Change the group of the files to the specified one.");
689 System.err.println(" -chmod MODE Change the permission of the files to the specified one.");
690 System.err.println(" -mappers Number of mappers to use during the copy (mapreduce.job.maps).");
691 System.err.println();
692 System.err.println("Examples:");
693 System.err.println(" hbase " + getClass() + " \\");
694 System.err.println(" -snapshot MySnapshot -copy-to hdfs:///srv2:8082/hbase \\");
695 System.err.println(" -chuser MyUser -chgroup MyGroup -chmod 700 -mappers 16");
696 System.exit(1);
697 }
698
699
700
701
702
703
704
705
706 static int innerMain(final Configuration conf, final String [] args) throws Exception {
707 return ToolRunner.run(conf, new ExportSnapshot(), args);
708 }
709
710 public static void main(String[] args) throws Exception {
711 System.exit(innerMain(HBaseConfiguration.create(), args));
712 }
713 }