[ovirt-users] ISO_DOMAIN by NFS behavior (if NFS is unavailable)

Hello List, i have just tried to backup and replace my ovirt-engine. My ovir-engine also provides the NFS share for the ISO Images. However, if i take that nfs share away my ovirt-nodes and cluster seems to fall apart. I get those typical NFS stale file handle symthoms. I can not umount or remount the NFS dirs anymore. Any idea how i can fix this or better: protect myself from such an NFS failure? Thanks, Mario