BCAM detects the failure of a channel adapter which will lead to the failure of a line and issues a console message (failure message, i.e. one of the messages BCA0990, BCA0991, BCA0996 or BCA0999). In such a case, BCAM automatically connects all the partner end systems assigned to the failed line to a line that is still operational and displays this end system switchover by means of console message BCA07B2. Existing connections are generally retained.
For active line monitoring BCAM uses a process based on ARP and reports problems it detects with a console message (timeout message, one of the messages BCA0925, BCA0955 or BCA0965).
To avoid impairing the functionality of this line monitoring mechanism, do not connect any components that perform filtering between the channel adapter and ethernet.
In addition, when the lines are activated BCAM switches all routes to the line which was the first one activated successfully. This action is also documented with the console message BCA07B2. The switchover can be prevented by initially defining the lines withAUTO-ROUTE-SWITCHING=*OFF and ROUTE-RESWITCHING=*OFF. Only after the lines and the associated node have been activated should the switching operations be permitted.
Once the reason for the failure has been removed, the original configuration can be restored while the system is running (reconfiguration). This can be done manually (see "Operation of routes").
Automatic reconfiguration occurs only when the lines concerned were edited with MODIFY(-VLAN)-LINE, AUTO-ROUTE-SWITCHING=*ON, ROUTE-RESWITING=*ON and SLOW-POLL=*ON. In other words, all the routes associated with a failed line will be reenabled with this setting only when the line is reactivated.
In the case of a VLAN, SLOW-POLL=*ON must be set in the assigned devices using the MODIFY-VLAN-DEVICE command.