In a Bright Cluster Manager HA setup, the database (MySQL/MariaDB) must remain perfectly synchronized between the active and standby head nodes to allow for a seamless transition. This synchronization typically occurs over a dedicated management or heartbeat network. If cmsh status shows the database service as [FAIL] on the secondary node, it almost always points to a communication breakdown. Without a stable network path, the secondary node cannot receive the binary logs from the primary node to keep its local copy up to date. While licensing (Option A) is important, a license failure usually disables management capabilities entirely rather than just the MySQL sync. Furthermore, head nodes are management servers and do not require GPU drivers (Option C) for their primary function. Ensuring low-latency, reliable connectivity between the two head nodes is the primary troubleshooting step for resolving "MySQL FAIL" states in BCM.