Bug #10197 Server closes connection
Submitted: 27 Apr 2005 8:31 Modified: 27 May 2005 13:43
Reporter: Magnus Zimmerman Email Updates:
Status: No Feedback Impact on me:
None 
Category:MySQL Server Severity:S2 (Serious)
Version:4.0.18 OS:Linux (RH ES 3 (update 2))
Assigned to: CPU Architecture:Any

[27 Apr 2005 8:31] Magnus Zimmerman 
Description:
I use 3 different JDBC connections towards MySQL. For a while everything works smoothly but suddenly I get the exception java.sql.SQLException: Communication link failure: java.io.EOFException, underlying cause: null from the driver when I try to perform ResultSet.next().

Since I couldn't see any error on the client side I ran tcpdump at the same as I performed the queries. I saw some really strange behaviour from the MySQL server. Suddenly I get a FIN,PSH,ACK packet and right after that the exception above is thrown.

How to repeat:
I have not found anything relevant on how to reproduce this bug. It is occuring at random intervals.
[27 Apr 2005 12:09] Magnus Zimmerman 
tcpdump of mysql cutting the connection

Attachment: db_error_69.dmp (application/octet-stream, text), 184.83 KiB.
[27 Apr 2005 12:10] Magnus Zimmerman 
The attached file shows how MySQL send a FIN,ACK,PSH packet to the client (packet 264) for no apparent reason.
[27 Apr 2005 13:43] Hartmut Holzgraefe 
Can you rule out that your server didn't run into net_write_timeout on one of your connections? (e.g. by having a delay of more than 60s between two result row fetches?)
[27 May 2005 23:00] Bugs System 
No feedback was provided for this bug for over a month, so it is
being suspended automatically. If you are able to provide the
information that was originally requested, please do so and change
the status of the bug back to "Open".