Hi , In HA while performing rollback , we use “hdfs namenode �Crollback” which would prompt user for confirmation. ( Implemented as part of HDFS-5138)
For Non-HA , as per doc if we perform rollback using “start-dfs.sh �Crollback” , then namenode startup hangs ( As it tries to start namenode in daemon mode , hence will not be able to prompt user for confirmation ) "main" prio=10 tid=0x000000000061d000 nid=0x3778 runnable [0x00007f5a573d8000] java.lang.Thread.State: RUNNABLE at java.io.FileOutputStream.writeBytes(Native Method) at java.io.FileOutputStream.write(FileOutputStream.java:345) at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:82) at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:140) - locked <0x00000000c868f3b0> (a java.io.BufferedOutputStream) at java.io.PrintStream.write(PrintStream.java:482) - locked <0x00000000c868f390> (a java.io.PrintStream) at sun.nio.cs.StreamEncoder.writeBytes(StreamEncoder.java:221) at sun.nio.cs.StreamEncoder.implFlushBuffer(StreamEncoder.java:291) at sun.nio.cs.StreamEncoder.flushBuffer(StreamEncoder.java:104) - locked <0x00000000c868f4e0> (a java.io.OutputStreamWriter) at java.io.OutputStreamWriter.flushBuffer(OutputStreamWriter.java:185) at java.io.PrintStream.write(PrintStream.java:527) - locked <0x00000000c868f390> (a java.io.PrintStream) at java.io.PrintStream.print(PrintStream.java:669) at java.io.PrintStream.println(PrintStream.java:806) - locked <0x00000000c868f390> (a java.io.PrintStream) Shall we update the document to perform Non-HA rollback using “hdfs namenode �Crollback “ and then start namenode ? ( which would be incompatible with previous version) Please provide your feedback on this issue. ________________________________ Andreina J 华为技术有限公司 Huawei Technologies Co., Ltd. [Company_logo] Phone: Fax: Mobile: Email: 地址:深圳市龙岗区坂田华为基地 邮编:518129 Huawei Technologies Co., Ltd. Bantian, Longgang District,Shenzhen 518129, P.R.China http://www.huawei.com ________________________________ 本邮件及其附件含有华为公司的保密信息,仅限于发送给上面地址中列出的个人或群组。禁 止任何其他人以任何形式使用(包括但不限于全部或部分地泄露、复制、或散发)本邮件中 的信息。如果您错收了本邮件,请您立即电话或邮件通知发件人并删除本邮件! This e-mail and its attachments contain confidential information from HUAWEI, which is intended only for the person or entity whose address is listed above. Any use of the information contained herein in any way (including, but not limited to, total or partial disclosure, reproduction, or dissemination) by persons other than the intended recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender by phone or email immediately and delete it!