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Application behavior when running in a mixed release environment
There are special application considerations when the Db2® Mirror nodes are running on different IBM® i operating system levels.
When the operating systems levels are different across the node pair, actions initiated from the node using the higher level operating system will fail if the replication action includes an enhancement which is unique to the higher level operating system. Operations and replication actions initiated from the node using the lower level system will not fail.
This means that if the mixed release environment consists of Node A (on IBM i 7.4) and Node B (on IBM i 7.5), replicated objects cannot use software enhancements that exist only on IBM i 7.5.
ALTER TABLE sales ADD RESTRICT ON DROP;
The attempt to execute this SQL statement will fail, because the RESTRICT ON DROP support only exists on IBM i 7.5. The DBE must wait until both nodes are running with IBM i 7.5 before establishing RESTRICT ON DROP on database files that are being replicated by Db2 Mirror.
- SQL statements fail with SQLCODE = -7061 and SQLSTATE = '55019' (reason code 1)
- CL commands fail with either CPFC922 (reason code 1), and possibly also CPF32AF (reason code 1)
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