[IMPALA-3628] Cancellation via shell may hang over SSL

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: Impala 2.5.0
• Fix Version/s: Impala 2.7.0, Impala 2.6.2
• Component/s: Clients
• Labels: kerberos security shell
• Target Version: Impala 2.7.0, Impala 2.6.2
• Assignee: Henry Robinson
• Reporter: Matthew Jacobs
• Created: 26/May/16 23:11
• Updated: 07/Oct/16 22:28
• Resolved: 05/Jul/16 22:39

Description

On an internal cluster with security enabled, it was reported that queries couldn't be cancelled via the shell. When the user tried to cancel the query via ctrl-C, the shell printed the warning:

^C Cancelling Query
Failed to reconnect and close (try 1/3): TSocket read 0 bytes
 Cancelling Query
Failed to reconnect and close (try 2/3): TSocket read 0 bytes
 Cancelling Query
Failed to reconnect and close (try 3/3): TSocket read 0 bytes

The shell did not return with a new prompt and the query was still active on the server until the query was manually cancelled via the web UI. At that point, the query was cancelled successfully, and the shell finally returned with the message:

Application Exception : Default TException.

This was using kerberos/ssl. It seemed to be reproducing regularly.