Forwarding Unknown VLANS CRS

RouterOS Beginner Basics
1

Can you please clarify the logic behind having the following default settings for :

forward-unknown-vlan (yes | no; Default: yes) Whether to allow forwarding VLANs which are not members of VLAN table.

Could we also start improving documentation. The default setting is set to Yes – the documentation does not stipulate nor describes how this forwarding will take place. In the Cisco world, unknown VLANs would be forwarded out “Trunk Ports”. In the case of the Mikrotik CRS Series, you have a setting set to a default of “Yes” without any description of its behavior.

2

Since at the beginning “/interface ethernet switch vlan” table is empty with no known VLANs configured if “forward-unknown-vlan” by default would be “NO”, then all traffic forwarding through CRS switch would be blocked. Access to the CPU from any ethernet or SFP port also would blocked and CRS switch could be configured only through Serial Console port which is not convenient.