> # Resolving Fabric Merge Conflicts

> Whenever two fabrics merge, SDV merges its database. A merge conflict can occur when there is a run-time information conflict or configuration mismatch. Run-time conflicts can occur due to:

> - Identical pWWNs have been assigned to different virtual devices.
> - The same virtual devices are assigned different pWWNs.
> - The virtual device and virtual FC ID are mismatched.

> A blank commit is a commit operation that does not contain configuration changes, and enforces the SDV configuration of the committing switch fabric-wide. A blank commit operation resolves merge conflicts by pushing the configuration from the committing switch throughout the fabric, which reinitializes the conflicting virtual devices. Exercise caution while performing this operation, as it can easily take some virtual devices offline.

> Merge failures resulting from a pWWN conflict can cause a failure with the device alias as well. A blank commit operation on a merge-failed VSAN within SDV should resolve the merge failure in the device alias.

> You can avoid merge conflicts due to configuration mismatch by ensuring that:

> - The pWWN and device alias entries for a virtual device are identical (in terms of primary and secondary).
> - There are no virtual device name conflicts across VSANs in fabrics.

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