# ==== Purpose ==== # # Changes replication topology. This file is normally sourced from # include/rpl_init.inc, but test cases can also source it if they # need to change topology after they have sourced include/rpl_init.inc # # This file sets up variables needed by include/rpl_sync.inc and many # other replication scripts in the include/ directory. It also issues # CHANGE MASTER on all servers where the configuration changes from # what it was before. It does not issue START SLAVE (use # include/rpl_start_slaves.inc for that). # # Note: it is not currently possible to change the number of servers # after the rpl_init.inc, without first calling rpl_end.inc. So the # test has to set $rpl_server_count to the total number of servers # that the test uses, before it sources include/rpl_init.inc. After # that, $rpl_server_count must not change until after next time the # test sources include/rpl_end.inc. # # Note: Since this script issues CHANGE MASTER, the test case must # ensure that all slaves where the configuration changes have stopped # both the IO thread and the SQL thread before this script is sourced. # # # ==== Usage ==== # # [--let $rpl_server_count= 7] # --let $rpl_topology= 1->2->3->1->4, 2->5, 6->7 # [--let $rpl_skip_change_master= 1] # [--let $rpl_master_log_file= 1:master-bin.000001,3:master-bin.000003] # [--let $rpl_master_log_pos= 1:4711,3:107] # [--let $rpl_debug= 1] # --source include/rpl_change_topology.inc # # Parameters: # $rpl_master_log_file # By default, CHANGE MASTER is executed with MASTER_LOG_FILE set # to the name of the last binlog file on the master (retrieved by # executing SHOW MASTER STATUS). This variable can be set to # specify another filename. This variable should be a # comma-separated list of the following form: # # SERVER_NUMBER_1:FILE_NAME_1,SERVER_NUMBER_2:FILE_NAME_2,... # # Before CHANGE MASTER is executed on server N, this script checks # if $rpl_master_log_file contains the text N:FILE_NAME. If it # does, then MASTER_LOG_FILE is set to FILE_NAME. Otherwise, # MASTER_LOG_FILE is set to the last binlog on the master. For # example, to specify that server_1 should start replicate from # master-bin.000007 and server_5 should start replicate from # master-bin.012345, do: # --let $rpl_master_log_file= 1:master-bin.000007,5:master-bin.012345 # # $rpl_master_log_pos # By default, CHANGE MASTER is executed without specifying the # MASTER_LOG_POS parameter. This variable can be set to set a # specific position. It has the same form as $rpl_master_log_file # (see above). For example, to specify that server_3 should start # replicate from position 4711 of its master, do: # --let $rpl_master_log_pos= 3:4711 # # $rpl_server_count, $rpl_topology, $rpl_debug, $rpl_skip_change_master # See include/rpl_init.inc # # # ==== Internal variables configured by this file ==== # # This file sets up the following variables, which are used by other # low-level replication files such as: # include/rpl_sync.inc # include/rpl_start_slaves.inc # include/rpl_stop_slaves.inc # include/rpl_end.inc # # $rpl_server_count_length: # Set to LENGTH($rpl_server_count). So if $rpl_server_count < 10, # then $rpl_server_count_length = 1; if 10 <= $rpl_server_count < # 100, then $rpl_server_count_length = 2, etc. # # $rpl_master_list # Set to a string consisting of $rpl_server_count numbers, each one # whitespace-padded to $rpl_server_count_length characters. If # server N is a slave, then the N'th number is the master of server # N. If server N is not a slave, then the N'th number is just spaces # (so in fact it is not a number). For example, if $rpl_topology is # '1->2,2->3,3->1,2->4,5->6', then $rpl_master_list is '3122 6'. # # $rpl_sync_chain_dirty # This variable is set to 1. This tells include/rpl_sync.inc to # compute a new value for $rpl_sync_chain next time that # include/rpl_sync.inc is sourced. See # include/rpl_generate_sync_chain.inc and include/rpl_sync.inc for # details. # Remove whitespace from $rpl_topology --let $rpl_topology= `SELECT REPLACE('$rpl_topology', ' ', '')` --let $include_filename= rpl_change_topology.inc [new topology=$rpl_topology] --source include/begin_include_file.inc if ($rpl_debug) { --echo ---- Check input ---- } if (`SELECT '$rpl_topology' = '' OR '$rpl_server_count' = ''`) { --die You must set $rpl_topology and $rpl_server_count before you source rpl_change_topology.inc. If you really want to change to the empty topology, set $rpl_topology= none } --let $_rpl_topology= $rpl_topology if (`SELECT '$_rpl_topology' = 'none'`) { --let $_rpl_topology= } if (`SELECT '!$rpl_master_list!' = '!!'`) { --die You must source include/rpl_init.inc before you source include/rpl_change_topology.inc } --let $_rpl_old_master_list= $rpl_master_list if ($rpl_debug) { --echo \$rpl_server_count='$rpl_server_count' --echo \$rpl_server_count_length='$rpl_server_count_length' --echo new \$rpl_topology='$_rpl_topology' --echo old \$rpl_master_list='$rpl_master_list' --echo old \$rpl_sync_chain='$rpl_sync_chain' } if ($rpl_debug) { --echo ---- Generate \$rpl_server_count_length and \$rpl_master_list ---- } --let $rpl_server_count_length= `SELECT LENGTH('$rpl_server_count')` --let $rpl_master_list= --let $_rpl_no_server= `SELECT REPEAT(' ', $rpl_server_count_length)` --let $rpl_master_list= `SELECT REPEAT('$_rpl_no_server', $rpl_server_count)` while ($_rpl_topology) { # Get 's1->s2' from 's1->s2->s3->...' or from 's1->s2,s3->s4,...' --let $_rpl_master_slave= `SELECT SUBSTRING_INDEX(SUBSTRING_INDEX('$_rpl_topology', ',', 1), '->', 2)` # Modify $_rpl_topology as follows: # - If it starts with 's1->s2,', remove 's1->s2,' # - If it starts with 's1->s2->', remove 's1->' # - If it is equal to 's1->s2', remove 's1->s2' --let $_rpl_topology= `SELECT SUBSTR('$_rpl_topology', IF(SUBSTR('$_rpl_topology', LENGTH('$_rpl_master_slave') + 1, 2) != '->', LENGTH('$_rpl_master_slave'), LOCATE('->', '$_rpl_master_slave')) + 2)` # Get 's1' from 's1->s2' --let $_rpl_master= `SELECT SUBSTRING_INDEX('$_rpl_master_slave', '->', 1)` # Get 's2' from 's1->s2' --let $_rpl_slave= `SELECT SUBSTRING('$_rpl_master_slave', LENGTH('$_rpl_master') + 3)` # Check that s2 does not have another master. if (`SELECT SUBSTR('$rpl_master_list', 1 + ($_rpl_slave - 1) * $rpl_server_count_length, $rpl_server_count_length) != '$_rpl_no_server'`) { --echo ERROR IN TEST: Server '$_rpl_slave' has more than one master in topology '$rpl_topology' --die ERROR IN TEST: found a server with more than one master in the $rpl_topology variable } # Save 's1' at position 's2' in $rpl_master_list --let $rpl_master_list= `SELECT INSERT('$rpl_master_list', 1 + ($_rpl_slave - 1) * $rpl_server_count_length, $rpl_server_count_length, RPAD('$_rpl_master', $rpl_server_count_length, ' '))` } if ($rpl_debug) { --echo new \$rpl_server_count_length = '$rpl_server_count_length' --echo new \$rpl_master_list = '$rpl_master_list' } if (!$rpl_skip_change_master) { if ($rpl_debug) { --echo ---- Execute CHANGE MASTER on all servers ---- } if (!$rpl_debug) { --disable_query_log } --let $_rpl_server= $rpl_server_count while ($_rpl_server) { # The following statement evaluates to: # 0, if server_$_rpl_server has the same master as before. # The master's server, if server_$_rpl_server is a slave. # The empty string, if server_$_rpl_server is not a slave. --let $_rpl_master= `SELECT TRIM(IFNULL(NULLIF(SUBSTRING('$rpl_master_list', 1 + ($_rpl_server - 1) * $rpl_server_count_length, $rpl_server_count_length), SUBSTRING('$_rpl_old_master_list', 1 + ($_rpl_server - 1) * $rpl_server_count_length, $rpl_server_count_length)), 0))` if ($rpl_debug) { --echo \$_rpl_server='$_rpl_server' \$_rpl_master='$_rpl_master' } if ($_rpl_master) { # Get port number --let $_rpl_port= \$SERVER_MYPORT_$_rpl_master # Get MASTER_LOG_FILE --let $_rpl_master_log_file_index= `SELECT LOCATE('$_rpl_server:', '$rpl_master_log_file')` if ($_rpl_master_log_file_index) { # Get text from after ':' and before ',', starting at # $_rpl_master_log_file --let $_rpl_master_log_file= `SELECT SUBSTRING_INDEX(SUBSTRING_INDEX(SUBSTRING('$rpl_master_log_file', $_rpl_master_log_file_index), ',', 1), ':', -1)` } if (!$_rpl_master_log_file_index) { --let $rpl_connection_name= server_$_rpl_master --source include/rpl_connection.inc --let $_rpl_master_log_file= query_get_value(SHOW MASTER STATUS, File, 1) } # Change connection. --let $rpl_connection_name= server_$_rpl_server --source include/rpl_connection.inc # Get MASTER_LOG_POS --let $_rpl_master_log_pos_index= `SELECT LOCATE('$_rpl_server:', '$rpl_master_log_pos')` if ($_rpl_master_log_pos_index) { --let $_rpl_master_log_pos= `SELECT SUBSTRING_INDEX(SUBSTRING_INDEX(SUBSTRING('$rpl_master_log_pos', $_rpl_master_log_pos_index), ',', 1), ':', -1)` --let $_rpl_master_log_pos= , MASTER_LOG_POS = $_rpl_master_log_pos } if (!$_rpl_master_log_pos_index) { --let $_rpl_master_log_pos= } eval CHANGE MASTER TO MASTER_HOST = '127.0.0.1', MASTER_PORT = $_rpl_port, MASTER_USER = 'root', MASTER_LOG_FILE = '$_rpl_master_log_file'$_rpl_master_log_pos, MASTER_CONNECT_RETRY = 1; } if (!$_rpl_master) { if (`SELECT '$_rpl_master' = ''`) { --let $rpl_connection_name= server_$_rpl_server --source include/rpl_connection.inc CHANGE MASTER TO MASTER_HOST = ''; } } --dec $_rpl_server } } --let $rpl_sync_chain_dirty= 1 --let $include_filename= rpl_change_topology.inc --source include/end_include_file.inc