About Cross-Protocol Locking

The SMB protocol assumes mandatory locking, but UNIX traditionally uses advisory locking. The Oracle Solaris OS can be configured to use mandatory locking on a per mount basis by using the non-blocking mandatory locking (nbmand) mount option.

When set, the nbmand mount option enforces mandatory cross-protocol share reservations and byte-range locking.

When the nbmand mount option is set, the SMB server enforces mandatory share reservations and byte-range locking internally for all SMB clients. If the nbmand mount option is not set, there is limited coordination with NFS and local processes.