/**
* Get the rootdir. Make sure its wholesome and exists before returning.
* @param rd
* @param conf
* @param fs
* @return hbase.rootdir (after checks for existence and bootstrapping if
* needed populating the directory with necessary bootup files).
* @throws IOException
*/
private Path checkRootDir(final Path rd, final Configuration c,
final FileSystem fs)
throws IOException {
// If FS is in safe mode wait till out of it.
FSUtils.waitOnSafeMode(c, c.getInt(HConstants.THREAD_WAKE_FREQUENCY,
10 * 1000));
// Filesystem is good. Go ahead and check for hbase.rootdir.
try {
if (!fs.exists(rd)) {
fs.mkdirs(rd);
// DFS leaves safe mode with 0 DNs when there are 0 blocks.
// We used to handle this by checking the current DN count and waiting until
// it is nonzero. With security, the check for datanode count doesn't work --
// it is a privileged op. So instead we adopt the strategy of the jobtracker
// and simply retry file creation during bootstrap indefinitely. As soon as
// there is one datanode it will succeed. Permission problems should have
// already been caught by mkdirs above.
FSUtils.setVersion(fs, rd, c.getInt(HConstants.THREAD_WAKE_FREQUENCY,
10 * 1000), c.getInt(HConstants.VERSION_FILE_WRITE_ATTEMPTS,
HConstants.DEFAULT_VERSION_FILE_WRITE_ATTEMPTS));
} else {
if (!fs.isDirectory(rd)) {
throw new IllegalArgumentException(rd.toString() + " is not a directory");
}
// as above
FSUtils.checkVersion(fs, rd, true, c.getInt(HConstants.THREAD_WAKE_FREQUENCY,
10 * 1000), c.getInt(HConstants.VERSION_FILE_WRITE_ATTEMPTS,
HConstants.DEFAULT_VERSION_FILE_WRITE_ATTEMPTS));
}
} catch (IllegalArgumentException iae) {
LOG.fatal("Please fix invalid configuration for "
+ HConstants.HBASE_DIR + " " + rd.toString(), iae);
throw iae;
}
// Make sure cluster ID exists
if (!FSUtils.checkClusterIdExists(fs, rd, c.getInt(
HConstants.THREAD_WAKE_FREQUENCY, 10 * 1000))) {
FSUtils.setClusterId(fs, rd, UUID.randomUUID().toString(), c.getInt(
HConstants.THREAD_WAKE_FREQUENCY, 10 * 1000));
}
clusterId = FSUtils.getClusterId(fs, rd);
// Make sure the root region directory exists!
if (!FSUtils.rootRegionExists(fs, rd)) {
bootstrap(rd, c);
}
createRootTableInfo(rd);
return rd;
}
