Fabric cluster mode
Fabric cluster mode is defined as a fabric in which the data path for nodes is distributed, but the configuration path is not distributed. Each node keeps its configuration database independently.
By default, the switch will boot up in fabric cluster mode and will attempt to form Inter-Switch Links (ISLs):
If the chassis is not connected to another switch, it forms a "single node VCS fabric." This means that the chassis operates as a standalone system, but the operational mode is always VCS-enabled. You cannot disable the VCS mode on any of the models listed above.