Hi, Chirs, It’s great to get your reply, I find I can continue the upgrade for detained. Two questions: 1. I always find the upgrade for detained very slow. Each datanode contains 20T data in my cluster, it take 30 minutes for upgrade approximately; 2. Currently is it possible to downgrade the nematode and datanode in my cluster? if so, what is the proper procedure.
--Jin > 在 2016年8月17日，上午2:22，Chris Nauroth <[email protected]> 写道： > > Hello, > > Running “hdfs dfsadmin -rollingUpgrade finalize” finalized the upgrade. This > is a terminal state for the upgrade process, so afterwards, it is no longer > possible to run “hdfs dfsadmin -rollingUpgrade downgrade”. > > Rolling upgrade supports upgrading individual daemons independent of other > daemons (e.g. just the DataNodes). If you want to proceed with upgrading > your 2.5.0 DataNodes to 2.7.2, then I expect you can start a new rolling > upgrade and proceed with the upgrade process on just the subset of DataNodes > still running 2.5.0. > --Chris Nauroth > > From: jinxing <[email protected]> > Date: Tuesday, August 16, 2016 at 6:02 AM > To: "[email protected]" <[email protected]> > Subject: hfs downgrade from 2.7.2 to 2.5.0 > > Hello, it’s great to join this mailing list. > > Can I ask a question? > > Is it possible to downgrade cluster ? > > I have already upgrade my cluster’s namenodes(with one stand by for HA) and > several datanodes from 2.5.0 folloing > https://hadoop.apache.org/docs/r2.7.2/hadoop-project-dist/hadoop-hdfs/HdfsRollingUpgrade.html#Downgrade_and_Rollback > > <https://hadoop.apache.org/docs/r2.7.2/hadoop-project-dist/hadoop-hdfs/HdfsRollingUpgrade.html#Downgrade_and_Rollback>; > > I take following steps: > 1. hdfs dfsadmin -rollingUpgrade prepare; > 2. hdfs dfsadmin -rollingUpgrade query; > 3. hdfs dfsadmin -shutdownDatanode <host:port> upgrade > 4. restart and upgrade datanode; > > However, I terminated the upgrade by mistake with command "hfs dfsadmin > -rollingUpgrade finalize" > > Currently, I have two 2.7.2 nematodes, and three 2.7.2 datanodes and 63 2.5.0 > datanodes; Now I want to downgrade the nematodes and datanodes from 2.7.2 > back to 2.5.0; > > But when I try to downgrade nematode and restart with “-rollingUpgrade > downgrade”, namenode cannot get started, I get rolling exception: > 2016-08-16 20:37:08,642 WARN > org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Encountered exception > loading fsimage > org.apache.hadoop.hdfs.server.common.IncorrectVersionException: Unexpected > version of storage directory /home/maintain/hadoop/data/hdfs-namenode. > Reported: -63. Expecting = -57. > at > org.apache.hadoop.hdfs.server.common.StorageInfo.setLayoutVersion(StorageInfo.java:178) > at > org.apache.hadoop.hdfs.server.common.StorageInfo.setFieldsFromProperties(StorageInfo.java:131) > at > org.apache.hadoop.hdfs.server.namenode.NNStorage.setFieldsFromProperties(NNStorage.java:608) > at > org.apache.hadoop.hdfs.server.common.StorageInfo.readProperties(StorageInfo.java:228) > at > org.apache.hadoop.hdfs.server.namenode.FSImage.recoverStorageDirs(FSImage.java:323) > at > org.apache.hadoop.hdfs.server.namenode.FSImage.recoverTransitionRead(FSImage.java:202) > at > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.loadFSImage(FSNamesystem.java:955) > at > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.loadFromDisk(FSNamesystem.java:700) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.loadNamesystem(NameNode.java:529) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:585) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:751) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:735) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1407) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1473) > 2016-08-16 20:37:08,645 INFO org.mortbay.log: Stopped > HttpServer2$SelectChannelConnectorWithSafeStartup@dx-pipe-sata61-pm:50070 > 2016-08-16 20:37:08,745 INFO > org.apache.hadoop.metrics2.impl.MetricsSystemImpl: Stopping NameNode metrics > system... > 2016-08-16 20:37:08,746 INFO > org.apache.hadoop.metrics2.impl.MetricsSystemImpl: NameNode metrics system > stopped. > 2016-08-16 20:37:08,746 INFO > org.apache.hadoop.metrics2.impl.MetricsSystemImpl: NameNode metrics system > shutdown complete. > 2016-08-16 20:37:08,746 FATAL > org.apache.hadoop.hdfs.server.namenode.NameNode: Exception in namenode join > org.apache.hadoop.hdfs.server.common.IncorrectVersionException: Unexpected > version of storage directory /home/maintain/hadoop/data/hdfs-namenode. > Reported: -63. Expecting = -57. > at > org.apache.hadoop.hdfs.server.common.StorageInfo.setLayoutVersion(StorageInfo.java:178) > at > org.apache.hadoop.hdfs.server.common.StorageInfo.setFieldsFromProperties(StorageInfo.java:131) > at > org.apache.hadoop.hdfs.server.namenode.NNStorage.setFieldsFromProperties(NNStorage.java:608) > at > org.apache.hadoop.hdfs.server.common.StorageInfo.readProperties(StorageInfo.java:228) > at > org.apache.hadoop.hdfs.server.namenode.FSImage.recoverStorageDirs(FSImage.java:323) > at > org.apache.hadoop.hdfs.server.namenode.FSImage.recoverTransitionRead(FSImage.java:202) > at > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.loadFSImage(FSNamesystem.java:955) > at > org.apache.hadoop.hdfs.server.namenode.FSNamesystem.loadFromDisk(FSNamesystem.java:700) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.loadNamesystem(NameNode.java:529) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:585) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:751) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:735) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1407) > at > org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1473) > > It’s great if someone can help? >
