Hi Zhenxing,
Good comments. Thanks a lot. I have updated it. Please review again. Thanks!
Best Regards,
Daogang
> Dao-Gang.Qu@stripped wrote:
>
>> #At file:///home/daogangq/mysql/bzrwork/bug45214/5.1-bt/ based on
> revid:davi.arnaut@stripped
>>
>> 2941 Dao-Gang.Qu@stripped 2009-07-01
>> Bug #45214 get_master_version_and_clock does not report error when queries
> fail
>>
>> The "get_master_version_and_clock(...)" function in sql/slave.cc ignores
>> error and passes directly when queries fail, or queries succeed
>> but the result retrieved is empty.
>>
>> The "get_master_version_and_clock(...)" function should try to reconnect
> master
>> if queries fail because of transient network problems, and fail otherwise.
>> The I/O thread should print a warning information if the queries succeed
>> but the result retrieved is empty.
>>
>
> The I/O thread should print a warning if the some system variables do
> not exist on master (very old master).
>
>
>>
>> @ mysql-test/extra/rpl_tests/rpl_get_master_version_and_clock.test
>> Test script for bug #45214
>> @ mysql-test/suite/rpl/r/rpl_get_master_version_and_clock.result
>> Test result for bug #45214
>> @ mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test
>> Test script for bug #45214
>> @ sql/slave.cc
>> Update the slave.cc for fixing bug #45214
>>
>> added:
>> mysql-test/extra/rpl_tests/rpl_get_master_version_and_clock.test
>> mysql-test/suite/rpl/r/rpl_get_master_version_and_clock.result
>> mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test
>> modified:
>> sql/slave.cc
>> === added file
> 'mysql-test/extra/rpl_tests/rpl_get_master_version_and_clock.test'
>> --- a/mysql-test/extra/rpl_tests/rpl_get_master_version_and_clock.test 1970-01-01
> 00:00:00 +0000
>> +++ b/mysql-test/extra/rpl_tests/rpl_get_master_version_and_clock.test 2009-07-01
> 02:53:02 +0000
>> @@ -0,0 +1,64 @@
>> +#
>> +# BUG#45214: http://bugs.mysql.com/bug.php?id=45214
>> +# The common part of the "rpl_get_master_version_and_clock" test.
>> +# Restart slave under network disconnection between slave and master
>> +# following the steps:
>> +# 1 - Got DBUG_SYNC_POINT lock
>> +# 2 - Set DBUG_SYNC_POINT before call mysql_real_query(...) function in
> get_master_version_and_clock(...) function and hang here
>> +# 3 - shutdown master server for simulating network disconnection
>> +# 4 - Release DBUG_SYNC_POINT lock
>> +# 5 - Check if the slave I/O thread tries to reconnect to master.
>> +#
>> +# Note: Please make sure initialize the $debug_lock when call the test script.
>> +#
>>
>
> Good
>
>
>> +connection slave;
>> +if (`SELECT '$debug_lock' = ''`)
>> +{
>> + --die Cannot continue. Please set value for $debug_lock.
>> +}
>> +
>> +# Restart slave
>> +--disable_warnings
>> +stop slave;
>> +source include/wait_for_slave_to_stop.inc;
>> +start slave;
>> +source include/wait_for_slave_to_start.inc;
>> +
>> +connection master;
>> +# Write file to make mysql-test-run.pl expect the "crash", but don't start
>> +# it until it's told to
>> +--write_file $MYSQLTEST_VARDIR/tmp/mysqld.1.expect
>> +wait
>> +EOF
>> +
>> +# Send shutdown to the connected server and give
>> +# it 10 seconds to die before zapping it
>> +shutdown_server 10;
>> +
>> +connection slave;
>> +eval SELECT RELEASE_LOCK($debug_lock);
>> +
>> +# Write file to make mysql-test-run.pl start up the server again
>> +--append_file $MYSQLTEST_VARDIR/tmp/mysqld.1.expect
>> +restart
>> +EOF
>> +
>> +connection master;
>> +# Turn on reconnect
>> +--enable_reconnect
>> +
>> +# Call script that will poll the server waiting for it to be back online again
>> +--source include/wait_until_connected_again.inc
>> +
>> +# Turn off reconnect again
>> +--disable_reconnect
>> +
>> +connection slave;
>> +source include/wait_for_slave_to_start.inc;
>> +
>> +# Show slave last IO errno
>> +let $last_io_errno= query_get_value("show slave status", Last_IO_Errno, 1);
>> +echo Slave_IO_Errno= $last_io_errno;
>> +
>> +
>> +# End of tests
>>
>> === added file 'mysql-test/suite/rpl/r/rpl_get_master_version_and_clock.result'
>> --- a/mysql-test/suite/rpl/r/rpl_get_master_version_and_clock.result 1970-01-01
> 00:00:00 +0000
>> +++ b/mysql-test/suite/rpl/r/rpl_get_master_version_and_clock.result 2009-07-01
> 02:53:02 +0000
>> @@ -0,0 +1,66 @@
>> +stop slave;
>> +drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
>> +reset master;
>> +reset slave;
>> +drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
>> +start slave;
>> +SELECT IS_FREE_LOCK("debug_lock.before_get_UNIX_TIMESTAMP");
>> +IS_FREE_LOCK("debug_lock.before_get_UNIX_TIMESTAMP")
>> +1
>> +SELECT GET_LOCK("debug_lock.before_get_UNIX_TIMESTAMP", 1000);
>> +GET_LOCK("debug_lock.before_get_UNIX_TIMESTAMP", 1000)
>> +1
>> +set global debug= 'd,debug_lock.before_get_UNIX_TIMESTAMP';
>> +stop slave;
>> +start slave;
>> +SELECT RELEASE_LOCK("debug_lock.before_get_UNIX_TIMESTAMP");
>> +RELEASE_LOCK("debug_lock.before_get_UNIX_TIMESTAMP")
>> +1
>> +Slave_IO_Errno= 2013
>> +SELECT IS_FREE_LOCK("debug_lock.before_get_SERVER_ID");
>> +IS_FREE_LOCK("debug_lock.before_get_SERVER_ID")
>> +1
>> +SELECT GET_LOCK("debug_lock.before_get_SERVER_ID", 1000);
>> +GET_LOCK("debug_lock.before_get_SERVER_ID", 1000)
>> +1
>> +set global debug= 'd,debug_lock.before_get_SERVER_ID';
>> +stop slave;
>> +start slave;
>> +SELECT RELEASE_LOCK("debug_lock.before_get_SERVER_ID");
>> +RELEASE_LOCK("debug_lock.before_get_SERVER_ID")
>> +1
>> +Slave_IO_Errno= 2013
>> +SELECT IS_FREE_LOCK("debug_lock.before_get_COLLATION_SERVER_VALUE");
>> +IS_FREE_LOCK("debug_lock.before_get_COLLATION_SERVER_VALUE")
>> +1
>> +SELECT GET_LOCK("debug_lock.before_get_COLLATION_SERVER_VALUE", 1000);
>> +GET_LOCK("debug_lock.before_get_COLLATION_SERVER_VALUE", 1000)
>> +1
>> +set global debug= 'd,debug_lock.before_get_COLLATION_SERVER_VALUE';
>> +stop slave;
>> +start slave;
>> +SELECT RELEASE_LOCK("debug_lock.before_get_COLLATION_SERVER_VALUE");
>> +RELEASE_LOCK("debug_lock.before_get_COLLATION_SERVER_VALUE")
>> +1
>> +Slave_IO_Errno= 2013
>> +SELECT IS_FREE_LOCK("debug_lock.before_get_TIME_ZONE_VALUE");
>> +IS_FREE_LOCK("debug_lock.before_get_TIME_ZONE_VALUE")
>> +1
>> +SELECT GET_LOCK("debug_lock.before_get_TIME_ZONE_VALUE", 1000);
>> +GET_LOCK("debug_lock.before_get_TIME_ZONE_VALUE", 1000)
>> +1
>> +set global debug= 'd,debug_lock.before_get_TIME_ZONE_VALUE';
>> +stop slave;
>> +start slave;
>> +SELECT RELEASE_LOCK("debug_lock.before_get_TIME_ZONE_VALUE");
>> +RELEASE_LOCK("debug_lock.before_get_TIME_ZONE_VALUE")
>> +1
>> +Slave_IO_Errno= 2013
>> +set global debug= '';
>> +reset master;
>> +include/stop_slave.inc
>> +change master to master_port=SLAVE_PORT;
>> +start slave;
>> +*** must be having the replicate-same-server-id IO thread error ***
>> +Slave_IO_Errno= 1593
>> +Slave_IO_Error= Fatal error: The slave I/O thread stops because master and slave
> have equal MySQL server ids; these ids must be different for replication to work (or the
> --replicate-same-server-id option must be used on slave but this does not always make
> sense; please check the manual before using it).
>>
>> === added file 'mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test'
>> --- a/mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test 1970-01-01
> 00:00:00 +0000
>> +++ b/mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test 2009-07-01
> 02:53:02 +0000
>> @@ -0,0 +1,76 @@
>> +#
>> +# BUG#45214: http://bugs.mysql.com/bug.php?id=45214
>> +# This test verifies if the slave I/O tread tries to reconnect to
>> +# master when it tries to get the values of the UNIX_TIMESTAMP, SERVER_ID,
>> +# COLLATION_SERVER and TIME_ZONE from master under network disconnection.
>> +# Finish the following tests by calling its common test script:
>> +# extra/rpl_tests/rpl_get_master_version_and_clock.test.
>> +# And meanwhile this test checks that the slave I/O thread refuses to start if
> slave
>> +# and master have the same server id (because this is a useless setup,
>> +# and otherwise SHOW SLAVE STATUS shows progress but all queries are
>> +# ignored, which has caught our customers), unless
>> +# --replicate-same-server-id.
>> +#
>> +
>> +source include/master-slave.inc;
>> +
>> +#Test case 1: Try to get the value of the UNIX_TIMESTAMP from master under
> network disconnection
>> +connection slave;
>> +let $debug_saved= `select @@global.debug`;
>> +
>> +let $debug_lock= "debug_lock.before_get_UNIX_TIMESTAMP";
>> +eval SELECT IS_FREE_LOCK($debug_lock);
>> +eval SELECT GET_LOCK($debug_lock, 1000);
>> +
>> +set global debug= 'd,debug_lock.before_get_UNIX_TIMESTAMP';
>> +source extra/rpl_tests/rpl_get_master_version_and_clock.test;
>> +
>> +#Test case 2: Try to get the value of the SERVER_ID from master under network
> disconnection
>> +connection slave;
>> +let $debug_lock= "debug_lock.before_get_SERVER_ID";
>> +eval SELECT IS_FREE_LOCK($debug_lock);
>> +eval SELECT GET_LOCK($debug_lock, 1000);
>> +
>> +set global debug= 'd,debug_lock.before_get_SERVER_ID';
>> +source extra/rpl_tests/rpl_get_master_version_and_clock.test;
>> +
>> +#Test case 3: Try to get the value of the COLLATION_SERVER from master under
> network disconnection
>> +connection slave;
>> +let $debug_lock= "debug_lock.before_get_COLLATION_SERVER_VALUE";
>> +eval SELECT IS_FREE_LOCK($debug_lock);
>> +eval SELECT GET_LOCK($debug_lock, 1000);
>> +
>> +set global debug= 'd,debug_lock.before_get_COLLATION_SERVER_VALUE';
>> +source extra/rpl_tests/rpl_get_master_version_and_clock.test;
>> +
>> +#Test case 4: Try to get the value of the TIME_ZONE from master under network
> disconnection
>> +connection slave;
>> +let $debug_lock= "debug_lock.before_get_TIME_ZONE_VALUE";
>> +eval SELECT IS_FREE_LOCK($debug_lock);
>> +eval SELECT GET_LOCK($debug_lock, 1000);
>> +
>> +set global debug= 'd,debug_lock.before_get_TIME_ZONE_VALUE';
>> +source extra/rpl_tests/rpl_get_master_version_and_clock.test;
>> +
>> +eval set global debug= '$debug_saved';
>> +
>> +#Test case 5: This test checks that the slave I/O thread refuses to start
>> +#if slave and master have the same server id.
>> +connection slave;
>> +reset master;
>> +# replicate ourselves
>> +source include/stop_slave.inc;
>> +--replace_result $SLAVE_MYPORT SLAVE_PORT
>> +eval change master to master_port=$SLAVE_MYPORT;
>> +start slave;
>> +
>> +let $slave_param= Last_IO_Errno;
>> +let $slave_param_value= 1593;
>> +source include/wait_for_slave_param.inc;
>> +--echo *** must be having the replicate-same-server-id IO thread error ***
>> +let $last_io_errno= query_get_value("show slave status", Last_IO_Errno, 1);
>> +let $last_io_error= query_get_value("show slave status", Last_IO_Error, 1);
>> +echo Slave_IO_Errno= $last_io_errno;
>> +echo Slave_IO_Error= $last_io_error;
>> +
>>
>
> Please also test that different configurations of COLLATION_SERVER and
> TIME_ZONE on master and slave will prevent slave to start.
>
>
>> +# End of tests
>>
>> === modified file 'sql/slave.cc'
>> --- a/sql/slave.cc 2009-06-09 16:44:26 +0000
>> +++ b/sql/slave.cc 2009-07-01 02:53:02 +0000
>> @@ -38,6 +38,7 @@
>> #include <my_dir.h>
>> #include <sql_common.h>
>> #include <errmsg.h>
>> +#include <mysqld_error.h>
>> #include <mysys_err.h>
>>
>> #ifdef HAVE_REPLICATION
>> @@ -842,6 +843,35 @@ int init_intvar_from_file(int* var, IO_C
>> DBUG_RETURN(1);
>> }
>>
>> +
>> +/*
>> + Check if the issue is caused by network.
>> +
>>
>
> I'd suggest to use work 'error' instead of 'issue', please also consider
> changing those below.
>
>
>> + RETURNS:
>> + TRUE network issue
>> + FALSE not network issue
>> +*/
>> +
>> +bool is_network_issue(MYSQL* mysql, Master_info* mi)
>> +{
>> + int errno;
>> + errno= mysql_errno(mysql);
>> + if (errno == CR_CONNECTION_ERROR ||
>> + errno == CR_CONN_HOST_ERROR ||
>> + errno == CR_SERVER_GONE_ERROR ||
>> + errno == CR_SERVER_LOST ||
>> + errno == ER_CON_COUNT_ERROR ||
>> + errno == ER_SERVER_SHUTDOWN)
>> + {
>> + mi->report(WARNING_LEVEL, errno, mysql_error(mysql));
>> + sql_print_error("network issue daogang test: %s, %d", mysql_error(mysql),
> errno);
>>
>
> Hmm, I think you forget to remove this line.
>
>
>> + return TRUE;
>> + }
>> +
>> + return FALSE;
>> +}
>> +
>> +
>> /*
>> Note that we rely on the master's version (3.23, 4.0.14 etc) instead of
>> relying on the binlog's version. This is not perfect: imagine an upgrade
>> @@ -854,6 +884,7 @@ int init_intvar_from_file(int* var, IO_C
>> RETURNS
>> 0 ok
>> 1 error
>> + 2 transient network problem, the caller should try to reconnect
>> */
>>
>> static int get_master_version_and_clock(MYSQL* mysql, Master_info* mi)
>> @@ -864,6 +895,7 @@ static int get_master_version_and_clock(
>> MYSQL_RES *master_res= 0;
>> MYSQL_ROW master_row;
>> DBUG_ENTER("get_master_version_and_clock");
>> + int query_re= 0;
>>
>> /*
>> Free old description_event_for_queue (that is needed if we are in
>> @@ -938,14 +970,26 @@ static int get_master_version_and_clock(
>> Compare the master and slave's clock. Do not die if master's clock is
>> unavailable (very old master not supporting UNIX_TIMESTAMP()?).
>> */
>> -
>> - if (!mysql_real_query(mysql, STRING_WITH_LEN("SELECT UNIX_TIMESTAMP()"))
> &&
>> - (master_res= mysql_store_result(mysql)) &&
>> - (master_row= mysql_fetch_row(master_res)))
>> + DBUG_SYNC_POINT("debug_lock.before_get_UNIX_TIMESTAMP", 10);
>> + query_re= mysql_real_query(mysql, STRING_WITH_LEN("SELECT
> UNIX_TIMESTAMP()"));
>> + if (query_re && is_network_issue(mysql, mi))
>> + DBUG_RETURN(2);
>> +
>> + master_res= mysql_store_result(mysql);
>> + if (!master_res && is_network_issue(mysql, mi))
>> + DBUG_RETURN(2);
>> +
>> + if (master_row= mysql_fetch_row(master_res))
>> {
>> mi->clock_diff_with_master=
>> (long) (time((time_t*) 0) - strtoul(master_row[0], 0, 10));
>> }
>> + else if (!master_row && is_network_issue(mysql, mi))
>> + {
>> + if (master_res)
>> + mysql_free_result(master_res);
>> + DBUG_RETURN(2);
>> + }
>> else if (!check_io_slave_killed(mi->io_thd, mi, NULL))
>> {
>> mi->clock_diff_with_master= 0; /* The "most sensible" value */
>> @@ -967,26 +1011,64 @@ static int get_master_version_and_clock(
>> Note: we could have put a @@SERVER_ID in the previous SELECT
>> UNIX_TIMESTAMP() instead, but this would not have worked on 3.23 masters.
>> */
>> - if (!mysql_real_query(mysql,
>> - STRING_WITH_LEN("SHOW VARIABLES LIKE 'SERVER_ID'"))
> &&
>> - (master_res= mysql_store_result(mysql)))
>> - {
>> - if ((master_row= mysql_fetch_row(master_res)) &&
>> - (::server_id == strtoul(master_row[1], 0, 10)) &&
>> - !mi->rli.replicate_same_server_id)
>> - {
>> - errmsg= "The slave I/O thread stops because master and slave have equal \
>> + DBUG_SYNC_POINT("debug_lock.before_get_SERVER_ID", 10);
>> + query_re= mysql_real_query(mysql, STRING_WITH_LEN("SHOW VARIABLES LIKE
> 'SERVER_ID'"));
>> + if (query_re)
>> + {
>> + if (is_network_issue(mysql, mi))
>> + DBUG_RETURN(2);
>> + /* Fatal error */
>> + sql_print_error(mysql_error(mysql));
>>
>
> Please use something like this: sql_print_error("Query \"SHOW VARIABLES
> LIKE 'SEVER_ID'\" failed with error: %s (%d)", mysql_error(mysql),
> mysql_errno(mysql));
>
> Please also change the following similar cases.
>
>
>> + errmsg= "The slave I/O thread stops because a fatal error is encountered \
>> +when it try to get the value of SERVER_ID variable from master.";
>> + err_code= ER_SLAVE_FATAL_ERROR;
>> + sprintf(err_buff, ER(err_code), errmsg);
>> + goto err;
>> + }
>> +
>> + master_res= mysql_store_result(mysql);
>> + if (!master_res)
>> + {
>> + /* Double check is required because some network issues will affect
>> + the execution of the "mysql_store_result()" function */
>> + if (is_network_issue(mysql, mi))
>> + DBUG_RETURN(2);
>> + /* Fatal error */
>> + sql_print_error(mysql_error(mysql));
>> + errmsg= "The slave I/O thread stops because a fatal error is encountered \
>> +when it try to get the value of SERVER_ID variable from master.";
>> + err_code= ER_SLAVE_FATAL_ERROR;
>> + sprintf(err_buff, ER(err_code), errmsg);
>> + goto err;
>> + }
>> +
>> + master_row= mysql_fetch_row(master_res);
>> + if (master_row && (::server_id == strtoul(master_row[1], 0, 10))
> &&
>> + !mi->rli.replicate_same_server_id)
>> + {
>> + errmsg= "The slave I/O thread stops because master and slave have equal \
>> MySQL server ids; these ids must be different for replication to work (or \
>> the --replicate-same-server-id option must be used on slave but this does \
>> not always make sense; please check the manual before using it).";
>> - err_code= ER_SLAVE_FATAL_ERROR;
>> - sprintf(err_buff, ER(err_code), errmsg);
>> + err_code= ER_SLAVE_FATAL_ERROR;
>> + sprintf(err_buff, ER(err_code), errmsg);
>> + }
>> + else if (!master_row)
>> + {
>> + if (is_network_issue(mysql, mi))
>> + {
>> + mysql_free_result(master_res);
>> + DBUG_RETURN(2);
>> }
>> - mysql_free_result(master_res);
>> - if (errmsg)
>> - goto err;
>> + else
>> + sql_print_warning("\"SHOW VARIABLES LIKE 'SERVER_ID'\" get empty result
> from master, \
>> +maybe it is a very old master.");
>> }
>> + mysql_free_result(master_res);
>>
>> + if (errmsg)
>> + goto err;
>> +
>> /*
>> Check that the master's global character_set_server and ours are the same.
>> Not fatal if query fails (old master?).
>> @@ -1008,13 +1090,51 @@ not always make sense; please check the
>> if (*mysql->server_version == '3')
>> goto err;
>>
>> - if ((*mysql->server_version == '4') &&
>> - !mysql_real_query(mysql,
>> - STRING_WITH_LEN("SELECT @@GLOBAL.COLLATION_SERVER"))
> &&
>> - (master_res= mysql_store_result(mysql)))
>> + if (*mysql->server_version == '4')
>> {
>> - if ((master_row= mysql_fetch_row(master_res)) &&
>> - strcmp(master_row[0],
> global_system_variables.collation_server->name))
>> + DBUG_SYNC_POINT("debug_lock.before_get_COLLATION_SERVER_VALUE", 10);
>> + query_re= mysql_real_query(mysql, STRING_WITH_LEN("SELECT
> @@GLOBAL.COLLATION_SERVER"));
>> + if (query_re)
>> + {
>> + if (is_network_issue(mysql, mi))
>> + DBUG_RETURN(2);
>> + if (mysql_errno(mysql) == ER_UNKNOWN_SYSTEM_VARIABLE)
>> + {
>> + sql_print_warning("\"SELECT @@GLOBAL.COLLATION_SERVER\" get empty
> result \
>> +from master, maybe it is a very old master.");
>>
>
> I'd suggest: "Unknown system variable 'COLLATION_SERVER' on master,
> maybe ..."
>
>
>> + goto cspass;
>>
>
> Please reorganize the code and remove this goto.
>
>
>> + }
>> + else
>> + {
>> + /* Fatal error */
>> + sql_print_error(mysql_error(mysql));
>> + errmsg= "The slave I/O thread stops because a fatal error is encountered
> \
>> +when it try to get the value of COLLATION_SERVER global variable from master.";
>> + err_code= ER_SLAVE_FATAL_ERROR;
>> + sprintf(err_buff, ER(err_code), errmsg);
>> + goto err;
>> + }
>> + }
>> +
>> + master_res= mysql_store_result(mysql);
>> + if (!master_res)
>> + {
>> + /* Double check is required because some network issues will affect
>> + the execution of the "mysql_store_result()" function */
>> + if (is_network_issue(mysql, mi))
>> + DBUG_RETURN(2);
>> + /* Fatal error */
>> + sql_print_error(mysql_error(mysql));
>> + errmsg= "The slave I/O thread stops because a fatal error is encountered
> \
>> +when it try to get the value of COLLATION_SERVER global variable from master.";
>> + err_code= ER_SLAVE_FATAL_ERROR;
>> + sprintf(err_buff, ER(err_code), errmsg);
>> + goto err;
>> + }
>> +
>> + master_row= mysql_fetch_row(master_res);
>> + if (master_row && strcmp(master_row[0],
>> +
> global_system_variables.collation_server->name))
>> {
>> errmsg= "The slave I/O thread stops because master and slave have \
>> different values for the COLLATION_SERVER global variable. The values must \
>> @@ -1022,10 +1142,16 @@ be equal for replication to work";
>> err_code= ER_SLAVE_FATAL_ERROR;
>> sprintf(err_buff, ER(err_code), errmsg);
>> }
>> + else if (!master_row && is_network_issue(mysql, mi))
>> + {
>> + mysql_free_result(master_res);
>> + DBUG_RETURN(2);
>> + }
>> mysql_free_result(master_res);
>> if (errmsg)
>> goto err;
>> }
>> +cspass:
>>
>> /*
>> Perform analogous check for time zone. Theoretically we also should
>> @@ -1042,13 +1168,42 @@ be equal for replication to work";
>> This check is only necessary for 4.x masters (and < 5.0.4 masters but
>> those were alpha).
>> */
>> - if ((*mysql->server_version == '4') &&
>> - !mysql_real_query(mysql, STRING_WITH_LEN("SELECT @@GLOBAL.TIME_ZONE"))
> &&
>> - (master_res= mysql_store_result(mysql)))
>> - {
>> - if ((master_row= mysql_fetch_row(master_res)) &&
>> - strcmp(master_row[0],
>> - global_system_variables.time_zone->get_name()->ptr()))
>> + if (*mysql->server_version == '4')
>> + {
>> + DBUG_SYNC_POINT("debug_lock.before_get_TIME_ZONE_VALUE", 10);
>> + query_re= mysql_real_query(mysql, STRING_WITH_LEN("SELECT
> @@GLOBAL.TIME_ZONE"));
>> + if (query_re)
>> + {
>> + if (is_network_issue(mysql, mi))
>> + DBUG_RETURN(2);
>> + /* Fatal error */
>> + sql_print_error(mysql_error(mysql));
>> + errmsg= "The slave I/O thread stops because a fatal error is encountered
> \
>> +when it try to get the value of TIME_ZONE global variable from master.";
>> + err_code= ER_SLAVE_FATAL_ERROR;
>> + sprintf(err_buff, ER(err_code), errmsg);
>> + goto err;
>> + }
>> +
>> + master_res= mysql_store_result(mysql);
>> + if (!master_res)
>> + {
>> + /* Double check is required because some network issues will affect
>> + the execution of the "mysql_store_result()" function */
>> + if (is_network_issue(mysql, mi))
>> + DBUG_RETURN(2);
>> + /* Fatal error */
>> + sql_print_error(mysql_error(mysql));
>> + errmsg= "The slave I/O thread stops because a fatal error is encountered
> \
>> +when it try to get the value of TIME_ZONE global variable from master.";
>> + err_code= ER_SLAVE_FATAL_ERROR;
>> + sprintf(err_buff, ER(err_code), errmsg);
>> + goto err;
>> + }
>> +
>> + master_row= mysql_fetch_row(master_res);
>> + if (master_row && strcmp(master_row[0],
>> +
> global_system_variables.time_zone->get_name()->ptr()))
>> {
>> errmsg= "The slave I/O thread stops because master and slave have \
>> different values for the TIME_ZONE global variable. The values must \
>> @@ -1056,6 +1211,11 @@ be equal for replication to work";
>> err_code= ER_SLAVE_FATAL_ERROR;
>> sprintf(err_buff, ER(err_code), errmsg);
>> }
>> + else if (!master_row && is_network_issue(mysql, mi))
>> + {
>> + mysql_free_result(master_res);
>> + DBUG_RETURN(2);
>> + }
>> mysql_free_result(master_res);
>>
>> if (errmsg)
>> @@ -2372,6 +2532,7 @@ pthread_handler_t handle_slave_io(void *
>> char llbuff[22];
>> uint retry_count;
>> bool suppress_warnings;
>> + int ret;
>> #ifndef DBUG_OFF
>> uint retry_count_reg= 0, retry_count_dump= 0, retry_count_event= 0;
>> #endif
>> @@ -2451,8 +2612,19 @@ connected:
>> mi->slave_running= MYSQL_SLAVE_RUN_CONNECT;
>> thd->slave_net = &mysql->net;
>> thd_proc_info(thd, "Checking master version");
>> - if (get_master_version_and_clock(mysql, mi))
>> + ret= get_master_version_and_clock(mysql, mi);
>> + if (ret == 1)
>> + /* Fatal error */
>> goto err;
>> +
>> + if (ret == 2)
>> + {
>> + /* Try to reconnect because the error was caused by a transient network
> problem */
>> + if (try_to_reconnect(thd, mysql, mi, &retry_count, suppress_warnings,
>> + reconnect_messages[SLAVE_RECON_ACT_REG]))
>> + goto err;
>> + goto connected;
>> + }
>>
>> if (mi->rli.relay_log.description_event_for_queue->binlog_version >
> 1)
>> {
>>
>>
>
>
