Extra steps are required to produce a Vault build containing the FoundationDB backend; attempts to use the backend on a build produced without following this procedure will fail with a descriptive error message at runtime.

The version of the Go bindings and the FoundationDB client library used to build them must match.

This version will determine the minimum API version that can be used, hence it should be no higher than the version of FoundationDB used in your cluster, and must also satisfy the requirements of the backend code.

The minimum required API version for the FoundationDB backend is 520.

Make sure you have Mono installed (core is enough), then install the Go bindings using the fdb-go-install.sh script:

$ physical/foundationdb/fdb-go-install.sh install --fdbver x.y.z

By default, if --fdbver x.y.z is not specified, version 5.2.4 will be used.

To build Vault the FoundationDB backend, add FDB_ENABLED=1 when invoking make, e.g.

$ make dev FDB_ENABLED=1

Similarly, add FDB_ENABLED=1 to your make invocation when running tests, e.g.

$ make test TEST=./physical/foundationdb FDB_ENABLED=1