Symptom
Snowflake JDBC connection could not be established after M2021 Update 10 if the snowflake server name contains underscores and connect to their Snowflake accounts over the private link.
In Strategy errors like "QueryEngine encountered error: Connect failed. Unable to connect.
Error type: System call error. Error communicating with connection process. Child Process hung: Command ConnectionConnectWithNewParameters. The target data source hasn't responded to the Connect request after 60 seconds. It may be stressed.." could occur. If we turn on the snowflake JDBC driver trace, error like
'Null response for cause: XXXX.privatelink.snowflakecomputing.com: Name or service not known' could be found in the trace log.
Cause
On Nov 16, Snowflake announced the JDBC driver behavior change that changes the default value of the allowUnderscoresInHost parameter to false. Details can be found in this article https://community.snowflake.com/s/article/Behaviour-Change-Release-information-associated-with-Snowflake-JDBC-driver-version-3-13-25
Action
There are 2 ways to workaround this. Details can also be found in this article https://community.snowflake.com/s/article/Behaviour-Change-Release-information-associated-with-Snowflake-JDBC-driver-version-3-13-25
