Since a NetBIOS proxy does not forward packets, the question of the virtual or physical addresses responded to is of no significance here. However, it is important that all routers and backup routers in the VRRP group can store the same host, group and server addresses learned from the remote site in their own database and propagate these upon connection establishment. This is the only method of ensuring that an NBNS request can be answered in every case.
Since the NetBIOS proxy propagates all host, group and server addresses learned from the remote site, it need only be ensured that this information is also recorded by the backup routers in their databases. Under normal circumstances, however, this is prevented by the route verification.
Since the transfer of addresses is usually prevented by the route verification, the addresses are only accepted in VRRP operation when all of the following requirements are fulfilled:
- There is a WAN route to the propagated address.
- The corresponding remote site is connected to a virtual router.
- The corresponding address is propagated by the master of this virtual router.
- The switch "Internal Services" is activated.
Only when all of these requirements are fulfilled, will the respective address be accepted in the database. This ensures that the individual router databases remain consistent and all addresses are immediately recognized when a backup router becomes master.
The position of the "Internal Services" switch influences the NetBIOS proxy.
- When it is enabled, the NetBIOS proxy accepts NBNS requests that are directed to virtual routers.
- If a virtual router is also connected to the default route, then this will be assigned as the NBNS server by the DHCP server in the LANCOM router.
- If more than one virtual router is connected by the default route, then the router with the highest priority will be assigned (as is the case with gateway addresses).
