diff --git a/ansible/mysql-deploy.yml b/ansible/mysql-deploy.yml
index 03184e7..db3badf 100644
--- a/ansible/mysql-deploy.yml
+++ b/ansible/mysql-deploy.yml
@@ -334,7 +334,7 @@
         # InnoDB redo log 容量：按内存梯度递增
         # ≤4G→128M、≤16G→256M、≤32G→512M、>32G→1G
         mysql_redo_capacity: >-
-          {{ innodb_redo_log_capacity if (innodb_redo_log_capacity is defined)
+          {{ innodb_redo_log_capacity if (innodb_redo_log_capacity is defined and (innodb_redo_log_capacity | string | lower) not in ['', 'auto'])
              else ('128M' if (mysql_memory_gb | int) <= 4
              else '256M' if (mysql_memory_gb | int) <= 16
              else '512M' if (mysql_memory_gb | int) <= 32