NDB Cluster Configuration Files This variable determines whether primary key reads are logged with exclusive locks, which allows for NDB Cluster Replication conflict detection and resolution based on read conflicts. To enable these locks, set the value of  ndb_log_exclusive_reads  to 1. 0, which disables such locking, is the default. For more information, see Read conflict detection and resolution. Shows whether the originating server ID and epoch are logged in the  ndb_binlog_index  table. Set using the  --ndb-log-orig  server option. This read-only, Boolean system variable shows whether a replica  mysqld  writes NDB transaction IDs in the binary log (required to use “active-active”  NDB Cluster Replication with  NDB$EPOCH_TRANS() conflict detection). To change the setting, use the  --ndb-log-transaction-id  option. ndb_log_transaction_id  is not supported in mainline MySQL Server 8.0. For more information, see Section 23.6.11, “NDB Cluster Replication Conflict Resolution” . 4184 • ndb_log_orig • ndb_log_transaction_id • ndb_metadata_check Command-Line Format --ndb-log-exclusive-reads[={OFF|ON}] System Variable ndb_log_exclusive_reads Scope Global, Session Dynamic Yes SET_VAR  Hint Applies No Type Boolean Default Value 0 Command-Line Format --ndb-log-orig[={OFF|ON}] System Variable ndb_log_orig Scope Global Dynamic No SET_VAR  Hint Applies No Type Boolean Default Value OFF System Variable ndb_log_transaction_id Scope Global Dynamic No SET_VAR  Hint Applies No Type Boolean Default Value OFF Command-Line Format --ndb-metadata-check[={OFF|ON}]