DRNC820V400R00 操作维护-20081111-B-V1.0.ppt

* After you know the concepts of active/standby workspaces, i will introduce MML commands for you : SYN BRDAREA: the command can be used to manually force load the files in the active/standby area of BAM to the Boards active/standby flash area. LOD BRD: the command can be used to forcibly load the host program, BOOTROM, data or DSP program in BAM to the FLASH of the board. SYN BAMAREA: the command can be used to manually synchronize the standby workspaces between the active and standby BAMs. * The heartbeat is messages without responses. Both the active and the standby BAMs send the heartbeat periodically. The dual-BAM system monitors the heartbeat to ensure that the active and the standby BAMs work properly and the network connection is normal. Three heartbeat channels between the active and standby BAMs: Internal network channel If the active and standby BAMs can receive the heartbeat from each other periodically in the three heartbeat channels, it is an indication that the communication and connection between two BAMs, internal network, and external network are normal. External network channel If no heartbeat message is received through anyone of the heartbeat channels within one minute, it is an indication that the heartbeat is interrupted. At this time, the active BAM reports the alarm. Backup channel connecting the BAMs If all the three heartbeat channels are interrupted for over five minutes and the communication of the standby BAM in the internal and external networks is normal, the standby BAM automatically switches to the active one * In dual-BAM mode, there are three modes of the switchover: forcible manual mode, fault-provoked automatic mode, and normal automatic mode: Forcible Manual Switchover ：we can use SWP BAM command. Fault-provoked Automatic Switchover ：The active BAM performs the functions while the standby BAM monitors the active one. If a fault occurs on the active BAM and lasts more than 5 minutes, the standby BAM automatically switches t