We don't pull schema during rolling upgrade, that is until
schema_tables_v3 feature is enabled on all nodes.
Because features are enabled from gossiper timer, there is a race
between feature enablement and processing of endpoint states which may
trigger schema pull. It can happen that we first try to pull, but
only later enable the feature. In that case the schema pull will not
happen until the next schema change.
The fix is to ensure that pulls abandoned due to feature not being enabled
will be retried when it is enabled.
Fixes sporadic failure in dtest:
repair_additional_test.py:RepairAdditionalTest.repair_schema_test
Message-Id: <1506428715-8182-2-git-send-email-tgrabiec@scylladb.com>
b704710954