https://support.microsoft.com/en-us/topic/kb4502706-fix-sql-server-generates-core-dump-with-failed-to-monitor-external-signals-in-sql-server-2017-fb2ede2d-835c-4207-2427-9d747aaf9705
KB4502706 - FIX: SQL Server generates core dump with "Failed to monitor external signals" in SQL...
FIX: SQL Server generates core dump with "Failed to monitor external signals" in SQL Server 2017