Shrijeet Paliwal just pointed me to this section in the HBase bookhttp://hbase.apache.org/upgrading.html#upgrade0.94 (thanks Shrijeet):
---- 1.3. Upgrading from 0.92.x to 0.94.x We used to think that 0.92 and 0.94 were interface compatible and that you can do a rolling upgrade between these versions but then we figured that HBASE-5357 Use builder pattern in HColumnDescriptor changed method signatures so rather than return void they instead return HColumnDescriptor. This will throw java.lang.NoSuchMethodError: org.apache.hadoop.hbase.HColumnDescriptor.setMaxVersions(I)V .... so 0.92 and 0.94 are NOT compatible. You cannot do a rolling upgrade between them. ---- Is that statement actually correct? The issue here is binary code compatibility, which we indeed do not support, but which does not impede rolling upgrades between versions (as long as we're wire compatible between releases, which we are). -- Lars
