In the DBSS 184.108.40.2064 Release Notes it states that passwords > 14 characters from Unix/Linux hosts is not supported:
SU-3951, SU-3887, SSDB-10052
Foglight for SQL Server on Windows systems: Users can now connect to the instance using a password that contains more than 14 characters. This feature is not supported when connecting from Linux/UNIX systems.
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