/// <summary>Create a new checkpoint</summary>
/// <exception cref="System.IO.IOException"/>
internal virtual void DoCheckpoint()
{
BackupImage bnImage = GetFSImage();
NNStorage bnStorage = bnImage.GetStorage();
long startTime = Time.MonotonicNow();
bnImage.FreezeNamespaceAtNextRoll();
NamenodeCommand cmd = GetRemoteNamenodeProxy().StartCheckpoint(backupNode.GetRegistration
());
CheckpointCommand cpCmd = null;
switch (cmd.GetAction())
{
case NamenodeProtocol.ActShutdown:
{
Shutdown();
throw new IOException("Name-node " + backupNode.nnRpcAddress + " requested shutdown."
);
}
case NamenodeProtocol.ActCheckpoint:
{
cpCmd = (CheckpointCommand)cmd;
break;
}
default:
{
throw new IOException("Unsupported NamenodeCommand: " + cmd.GetAction());
}
}
bnImage.WaitUntilNamespaceFrozen();
CheckpointSignature sig = cpCmd.GetSignature();
// Make sure we're talking to the same NN!
sig.ValidateStorageInfo(bnImage);
long lastApplied = bnImage.GetLastAppliedTxId();
Log.Debug("Doing checkpoint. Last applied: " + lastApplied);
RemoteEditLogManifest manifest = GetRemoteNamenodeProxy().GetEditLogManifest(bnImage
.GetLastAppliedTxId() + 1);
bool needReloadImage = false;
if (!manifest.GetLogs().IsEmpty())
{
RemoteEditLog firstRemoteLog = manifest.GetLogs()[0];
// we don't have enough logs to roll forward using only logs. Need
// to download and load the image.
if (firstRemoteLog.GetStartTxId() > lastApplied + 1)
{
Log.Info("Unable to roll forward using only logs. Downloading " + "image with txid "
+ sig.mostRecentCheckpointTxId);
MD5Hash downloadedHash = TransferFsImage.DownloadImageToStorage(backupNode.nnHttpAddress
, sig.mostRecentCheckpointTxId, bnStorage, true);
bnImage.SaveDigestAndRenameCheckpointImage(NNStorage.NameNodeFile.Image, sig.mostRecentCheckpointTxId
, downloadedHash);
lastApplied = sig.mostRecentCheckpointTxId;
needReloadImage = true;
}
if (firstRemoteLog.GetStartTxId() > lastApplied + 1)
{
throw new IOException("No logs to roll forward from " + lastApplied);
}
// get edits files
foreach (RemoteEditLog log in manifest.GetLogs())
{
TransferFsImage.DownloadEditsToStorage(backupNode.nnHttpAddress, log, bnStorage);
}
if (needReloadImage)
{
Log.Info("Loading image with txid " + sig.mostRecentCheckpointTxId);
FilePath file = bnStorage.FindImageFile(NNStorage.NameNodeFile.Image, sig.mostRecentCheckpointTxId
);
bnImage.ReloadFromImageFile(file, backupNode.GetNamesystem());
}
RollForwardByApplyingLogs(manifest, bnImage, backupNode.GetNamesystem());
}
long txid = bnImage.GetLastAppliedTxId();
backupNode.namesystem.WriteLock();
try
{
backupNode.namesystem.SetImageLoaded();
if (backupNode.namesystem.GetBlocksTotal() > 0)
{
backupNode.namesystem.SetBlockTotal();
}
bnImage.SaveFSImageInAllDirs(backupNode.GetNamesystem(), txid);
bnStorage.WriteAll();
}
finally
{
backupNode.namesystem.WriteUnlock();
}
if (cpCmd.NeedToReturnImage())
{
TransferFsImage.UploadImageFromStorage(backupNode.nnHttpAddress, conf, bnStorage,
NNStorage.NameNodeFile.Image, txid);
}
GetRemoteNamenodeProxy().EndCheckpoint(backupNode.GetRegistration(), sig);
if (backupNode.GetRole() == HdfsServerConstants.NamenodeRole.Backup)
{
bnImage.ConvergeJournalSpool();
}
backupNode.SetRegistration();
// keep registration up to date
long imageSize = bnImage.GetStorage().GetFsImageName(txid).Length();
Log.Info("Checkpoint completed in " + (Time.MonotonicNow() - startTime) / 1000 +
" seconds." + " New Image Size: " + imageSize);
}
public virtual void TestBackupNodeTailsEdits()
{
Configuration conf = new HdfsConfiguration();
HAUtil.SetAllowStandbyReads(conf, true);
MiniDFSCluster cluster = null;
FileSystem fileSys = null;
BackupNode backup = null;
try
{
cluster = new MiniDFSCluster.Builder(conf).NumDataNodes(0).Build();
fileSys = cluster.GetFileSystem();
backup = StartBackupNode(conf, HdfsServerConstants.StartupOption.Backup, 1);
BackupImage bnImage = (BackupImage)backup.GetFSImage();
TestBNInSync(cluster, backup, 1);
// Force a roll -- BN should roll with NN.
NameNode nn = cluster.GetNameNode();
NamenodeProtocols nnRpc = nn.GetRpcServer();
nnRpc.RollEditLog();
NUnit.Framework.Assert.AreEqual(bnImage.GetEditLog().GetCurSegmentTxId(), nn.GetFSImage
().GetEditLog().GetCurSegmentTxId());
// BN should stay in sync after roll
TestBNInSync(cluster, backup, 2);
long nnImageBefore = nn.GetFSImage().GetStorage().GetMostRecentCheckpointTxId();
// BN checkpoint
backup.DoCheckpoint();
// NN should have received a new image
long nnImageAfter = nn.GetFSImage().GetStorage().GetMostRecentCheckpointTxId();
NUnit.Framework.Assert.IsTrue("nn should have received new checkpoint. before: "
+ nnImageBefore + " after: " + nnImageAfter, nnImageAfter > nnImageBefore);
// BN should stay in sync after checkpoint
TestBNInSync(cluster, backup, 3);
// Stop BN
Storage.StorageDirectory sd = bnImage.GetStorage().GetStorageDir(0);
backup.Stop();
backup = null;
// When shutting down the BN, it shouldn't finalize logs that are
// still open on the NN
FileJournalManager.EditLogFile editsLog = FSImageTestUtil.FindLatestEditsLog(sd);
NUnit.Framework.Assert.AreEqual(editsLog.GetFirstTxId(), nn.GetFSImage().GetEditLog
().GetCurSegmentTxId());
NUnit.Framework.Assert.IsTrue("Should not have finalized " + editsLog, editsLog.IsInProgress
());
// do some edits
NUnit.Framework.Assert.IsTrue(fileSys.Mkdirs(new Path("/edit-while-bn-down")));
// start a new backup node
backup = StartBackupNode(conf, HdfsServerConstants.StartupOption.Backup, 1);
TestBNInSync(cluster, backup, 4);
NUnit.Framework.Assert.IsNotNull(backup.GetNamesystem().GetFileInfo("/edit-while-bn-down"
, false));
}
finally
{
Log.Info("Shutting down...");
if (backup != null)
{
backup.Stop();
}
if (fileSys != null)
{
fileSys.Close();
}
if (cluster != null)
{
cluster.Shutdown();
}
}
AssertStorageDirsMatch(cluster.GetNameNode(), backup);
}
/// <summary>Register this backup node with the active name-node.</summary>
/// <param name="nsInfo">namespace information</param>
/// <exception cref="System.IO.IOException"/>
private void RegisterWith(NamespaceInfo nsInfo)
{
BackupImage bnImage = (BackupImage)GetFSImage();
NNStorage storage = bnImage.GetStorage();
// verify namespaceID
if (storage.GetNamespaceID() == 0)
{
// new backup storage
storage.SetStorageInfo(nsInfo);
storage.SetBlockPoolID(nsInfo.GetBlockPoolID());
storage.SetClusterID(nsInfo.GetClusterID());
}
else
{
nsInfo.ValidateStorage(storage);
}
bnImage.InitEditLog(HdfsServerConstants.StartupOption.Regular);
SetRegistration();
NamenodeRegistration nnReg = null;
while (!IsStopRequested())
{
try
{
nnReg = namenode.RegisterSubordinateNamenode(GetRegistration());
break;
}
catch (SocketTimeoutException e)
{
// name-node is busy
Log.Info("Problem connecting to name-node: " + nnRpcAddress);
try
{
Sharpen.Thread.Sleep(1000);
}
catch (Exception)
{
Log.Warn("Encountered exception ", e);
}
}
}
string msg = null;
if (nnReg == null)
{
// consider as a rejection
msg = "Registration rejected by " + nnRpcAddress;
}
else
{
if (!nnReg.IsRole(HdfsServerConstants.NamenodeRole.Namenode))
{
msg = "Name-node " + nnRpcAddress + " is not active";
}
}
if (msg != null)
{
msg += ". Shutting down.";
Log.Error(msg);
throw new IOException(msg);
}
// stop the node
nnRpcAddress = nnReg.GetAddress();
}