Is Red Hat GFS(Global File System) is certified by Oracle for use with Oracle Real Application Clusters?

Sistina Cluster Filesystem is not part of the standard RedHat kernel and therefore is not certified by Oracle but falls under a kernel extension. This however, does not mean that Oracle RAC is not certified with it. As a fact, Oracle RAC does not certify against a filesystem per se, but certifies against an operating system. If, as is the case with Sistina filesystem, the filesystem is certified with the operating system, this only means that the Oracle does not provide direct support and fix the filesystem in case of an error. Customer will have to contact the filesystem provider for support.