While running continuous ingest against 1.7.4-rc0 I saw a lot of warning like the followng.
The warning are generated by TabletServerLogger.java line 341 when a write ahead log is closed. Write ahead logs are closed as part of normal operations as seen on TabletServerLogger.java line 386. There should not be a warning when this happens. This is caused by changes made for
ACCUMULO-4777. Before these changes this event was logged at debug. At this time, these changes have not been released. It would be nice to fix this before releasing 1.7.4