Hello, For more background, I recommend reviewing the documentation on HDFS HA with Quorum Journal Manager, particularly the Architecture section:
http://hadoop.apache.org/docs/current/hadoop-yarn/hadoop-yarn-site/HDFSHighAvailabilityWithQJM.html To summarize, edit logs are replicated, but it happens via interaction with a separate set of daemons called the journal nodes. The active persists its edit logs to a majority of journal nodes (deployed in multiple). The standby reads the edits from the journal nodes and applies them locally. The separate journal nodes provide redundancy, so that edits don't need to be blocked if a single node dies. By continuously reading the edits, the standby can stay up to date with changes applied at the active and failover quickly if needed. Chris Nauroth Hortonworks http://hortonworks.com/ On Sat, Nov 9, 2013 at 7:29 PM, origin <[email protected]> wrote: > Hey guys: > I was curious that why Active NameNode do not repilcation edits log to > Standby NameNode like MySQL dose? -- CONFIDENTIALITY NOTICE NOTICE: This message is intended for the use of the individual or entity to which it is addressed and may contain information that is confidential, privileged and exempt from disclosure under applicable law. If the reader of this message is not the intended recipient, you are hereby notified that any printing, copying, dissemination, distribution, disclosure or forwarding of this communication is strictly prohibited. If you have received this communication in error, please contact the sender immediately and delete it from your system. Thank You.
