Linux- HOST HA / DRBD overview

Learn how Host High Availability (HA) and DRBD operate within your IBM® Netezza Appliance.

Distributed Replicated Block Device (DRBD) is a distributed replicated block storage software for the Linux platform, widely used in high-performance, high-availability (HA) environments. DRBD functions as a block device driver that mirrors the content of block devices between two or more hosts.

DRBD usage in Netezza

Netezza leverages DRBD replication specifically for the following partition:/opt/appliance/storage/nps. As new data is written to the partition on the primary host, DRBD automatically replicates those changes to the same partition on the standby host. This ensures data consistency and minimizes the risk of data loss during a failover.

Synchronous replication

Netezza implements DRBD in synchronous mode (Protocol C), which provides tightly coupled mirroring. A write operation is not considered complete on the primary host until it has been successfully written to both the active and the standby hosts. The primary host must receive an acknowledgement from the standby host confirming that the write is complete. This approach ensures that no transactions are lost if a failover occurs, which is critical for HA environments.

For detailed documentation on DRBD concepts, configuration, and operations, see Linbit DRBD documentation.