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  1. Apache Cassandra
  2. CASSANDRA-8715

Possible Deadlock in Cqlsh in a Kerberos-enabled environment when using "COPY ... FROM ..."

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Details

    • Bug
    • Status: Resolved
    • Low
    • Resolution: Cannot Reproduce
    • 2.1.5
    • None
    • Cassandra 2.1.2.160, cqlsh 5.0.1, Native protocol v3

    • Low

    Description

      When running a COPY ... FROM ... command in a Kerberos environment, I see the number of rows processed, but eventually, Cqlsh never returns. I can verify, that all the data was copied, but the progress bar shows me the last shown info and cqlsh hangs there and never returns.

      Please note that this issue did not occur in the exact same environment with Cassandra 2.0.12.156.

      With the help of Tyler Hobbs, I investigated the problem a little bit further and added some debug statements at specific points. For example, in the CountdownLatch class at https://github.com/apache/cassandra/blob/a323a1a6d5f28ced1a51ba559055283f3eb356ff/pylib/cqlshlib/async_insert.py#L35-L36 I can see that the counter always stays above zero and therefore never returns (even when the data to be copied is already copied).

      I've also seen that somehow when I type in one cqlsh command, there will be actually two commands. Let me give you an example:

      I added a debug statement just before https://github.com/apache/cassandra/blob/d76450c7986202141f3a917b3623a4c3138c1094/bin/cqlsh#L920

      cqlsh> use libdata ;

      2015-01-30 18:54:56,113 [DEBUG] root: STATEMENT: [('K_USE', 'use', (0, 3)), ('identifier', 'libdata', (4, 11)), ('endtoken', ';', (12, 13))]

      2015-01-30 18:54:56,113 [DEBUG] root: STATEMENT: [('K_USE', 'use', (0, 3)), ('identifier', 'libdata', (4, 11)), ('endtoken', ';', (12, 13))]
      

      and saw that all commands I enter, they end up being executed twice (same goes for the COPY command).

      If I can provide any other input for debugging purposes, please let me know.

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            thobbs Tom Hobbs
            eduard.tudenhoefner Eduard Tudenhoefner
            Tom Hobbs
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              Created:
              Updated:
              Resolved: