Build tested: 1.4.2-1 (Azure build 20191224.6)
In this release, ColumnStore engine becomes part of the MariaDB server (Instead of ColumnStore use the server code to build its own distribution package). When server RPM or DEB package is installed, mysqld starts automatically. The running mysqld process causes postConfigure to exit prematurely. A work around is to use the OAM command "mcsadmin shutdownsystem y" to shutdown any ColumnStore processes, including mysqld, before running postConfigure.
There are couple options to fix this issue:
1) Add the work around above to the installation instruction
2) Add the work around command to the columnstore-post-install script