/// <summary> /// Confirm that FSImage files in all StorageDirectory are the same, /// and non-empty, and there are the expected number of them. /// </summary> /// <param name="fsn">- the FSNamesystem being checked.</param> /// <param name="numImageDirs">- the configured number of StorageDirectory of type IMAGE. /// </param> /// <returns>- the md5 hash of the most recent FSImage files, which must all be the same. /// </returns> /// <exception cref="System.Exception"> /// if image files are empty or different, /// if less than two StorageDirectory are provided, or if the /// actual number of StorageDirectory is less than configured. /// </exception> public static string CheckImages(FSNamesystem fsn, int numImageDirs) { NNStorage stg = fsn.GetFSImage().GetStorage(); //any failed StorageDirectory is removed from the storageDirs list NUnit.Framework.Assert.AreEqual("Some StorageDirectories failed Upgrade", numImageDirs , stg.GetNumStorageDirs(NNStorage.NameNodeDirType.Image)); NUnit.Framework.Assert.IsTrue("Not enough fsimage copies in MiniDFSCluster " + "to test parallel write" , numImageDirs > 1); // List of "current/" directory from each SD IList <FilePath> dirs = FSImageTestUtil.GetCurrentDirs(stg, NNStorage.NameNodeDirType .Image); // across directories, all files with same names should be identical hashes FSImageTestUtil.AssertParallelFilesAreIdentical(dirs, Sharpen.Collections.EmptySet <string>()); FSImageTestUtil.AssertSameNewestImage(dirs); // Return the hash of the newest image file Storage.StorageDirectory firstSd = stg.DirIterator(NNStorage.NameNodeDirType.Image ).Next(); FilePath latestImage = FSImageTestUtil.FindLatestImageFile(firstSd); string md5 = FSImageTestUtil.GetImageFileMD5IgnoringTxId(latestImage); System.Console.Error.WriteLine("md5 of " + latestImage + ": " + md5); return(md5); }