HI Xian, > I'm wondering whether I should back up the hbase master or not. Is > there any possibility of data loss if I don't back up the hbase master?
Well if you do not take the backup of Hbase Master, then you will not be able to access your data present in HDFS but since the data is on HDFS so data is not lost. Here I am assuming that your HDFS cluster is up and running. If you take Backup Hbase Master, then once your Hbase Master is down , after some time Backup Hbase Master will become Hbase Master and you will be able to access your data as before. In both case if your HDFS cluster is running fine, then your data is safe. Hope this helps! Stuti -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Stack Sent: Thursday, October 20, 2011 9:33 PM To: [email protected] Subject: Re: questions about multiple masters On Wed, Oct 19, 2011 at 11:59 PM, Xian Woo <[email protected]> wrote: > I'm wondering whether I should back up the hbase master or not. Is > there any possibility of data loss if I don't back up the hbase master? > No. Master does not hold 'state'. Any state it needs it keeps out in zookeeper. > Also, if I back up the hbase master and hope that the backup hbase > master continues to work when the real master not working, should I > separate the hbase master from the hadoop namenode? Here is my > concern: As you know, when the master of the cluster went down, the > cluster would crash(since the namenode is on the master node). And I > suppose the backup master would not get to work until the hadoop > cluster back to normal. > That is right. HBase won't work when NameNode is down. St.Ack ::DISCLAIMER:: ----------------------------------------------------------------------------------------------------------------------- The contents of this e-mail and any attachment(s) are confidential and intended for the named recipient(s) only. It shall not attach any liability on the originator or HCL or its affiliates. Any views or opinions presented in this email are solely those of the author and may not necessarily reflect the opinions of HCL or its affiliates. Any form of reproduction, dissemination, copying, disclosure, modification, distribution and / or publication of this message without the prior written consent of the author of this e-mail is strictly prohibited. If you have received this email in error please delete it and notify the sender immediately. Before opening any mail and attachments please check them for viruses and defect. -----------------------------------------------------------------------------------------------------------------------
