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Phil Yang commented on HBASE-17931: ----------------------------------- HDFS has similar command "dfsadmin -rollingUpgrade xxx". But it will make the process of rolling upgrade more complicated in the future HBase releases? > Rolling upgrade on branch-1 and master > -------------------------------------- > > Key: HBASE-17931 > URL: https://issues.apache.org/jira/browse/HBASE-17931 > Project: HBase > Issue Type: Bug > Components: scan > Affects Versions: 1.4.0 > Reporter: Phil Yang > Priority: Blocker > Fix For: 2.0.0 > > > In branch-1 and master we have some improvement and new features on scanning > which is not compatible. > A client of old version to a server of new version is compatible (must be a > bug if not, maybe need some test?). > A client of new version may not be able to read from a server of old version > correctly (because of scan limit, moreResults flag, etc), which is ok for > major/minor upgrade and we can tell users to upgrade server before upgrading > client. But RS also use scan to read meta. If meta table is in RS of old > version, all RSs of new version may have trouble while scanning meta table. > So we should make sure meta table always in servers of new version. Force > meta table in Master and upgrade Master first, or assign meta table in region > servers with latest version? -- This message was sent by Atlassian JIRA (v6.3.15#6346)