The Address Conflict Detection method requires that communication systems implement the steps described below. Detailed information is provided in RFC5227.
“Address Probing”
With ARP probe, it is reported while the (VLAN) line is being activated that the address noted in the log will be used and the systems are waiting for the response from the network.
“Address Announcing”
With ARP announce, when the (VLAN) line is activated it is announced that after a defined wait time the address noted in the log will be used.
“Conflict Detection”
If an address conflict has already been detected when the (VLAN) line is activated, the address cannot be used. Access via this network connection is not possible using this address. This network connection consequently does not become active. A message which must be answered is output to the console.
“Defense”
In ongoing operation you must protect the address in such a way that no other processor uses this IP address. This mechanism is used cyclically.
Information in “case of conflict”
The following BCAM messages are used to display conflict situations: BCA08C7, BCA08C8, BCA08C9 and BCA08CA. The messages are output to the console.
In addition to the (VLAN) line name, the address is also logged in the deactivation messages. In the case of the warning messages BCA08C8 and BCA08CA the MAC address received is also logged, which permits conclusions to be drawn about partner end system which caused problems.