Request for improved recovery options

Other Ideas for different product enhancements/feature request based on customer experience.

• Rebuild EM doesnt exist in CS 5- currently only works in CS 6+ and has no official documentation

• Rebuild EM should work with S3 clusters - currently only works with single node deployments if it has access to all dbroots (meaning non-ha clusters is complicated to use or not possible)

• make periodic copies of the BRM_saves_journal - Brm_saves should keep A & B copies of the BRM_saves_journal to reduce the timeframe of dataloss and/or load_brm should attempt more auto recovery options with its own saves A & B files

• maxscale should work with cmapi- Putting a node in maintenance mode in maxscale should work with cmapi or cmapi should notice the maintenance flag and safely remove the node from the columnstore cluster

• debug utility to cleanup extent map (BRM_saves_em) - a debug utility should exist to find orphaned objects/ extent files to either delete them

Current Rebuild EM Notes
Internal Link: https://mariadbcorp.atlassian.net/wiki/spaces/Support/pages/1576632337/Rebuild+the+extent+map