Synchronous Replication LUN Map Inconsistency  

Result: DR failure and data corruption  

The signature

LUN Map Inconsistency

The impact

The impact of LUN map inconsistency may seam less critical than non-replicated data, however the impact is to local or remote data availability and data corruption.

Technical details

In this example the production database is on a volume group that consists of three storage volumes. The production host is dual-pathed to the SAN, with two HBA’s. Each storage volume should be presented down both HBA’s with software such as PowerPath or DMP managing the paths. One storage volume is missing a path. Should that path fail due to HBA, SAN switch or array port, failure the database would be corrupted.

Can it happen to me?

This is a common gap found in highly evolving environments were storage teams are under pressure to meet the growing storage demand. These gaps are a created during normal zoning and/or LUN masking procedures that provisioning tools do not alert or prevent from occurring.