The RTN 950 was displaying "SYNC_DISABLE" alarm and customer was complaining that when the primary control board switches to the backup control board, the services were stopping.
RTN 950 version: V100R001C02SPC200
Control Board CXP Verison: 5.76.01.33
SYNC_DISABLE alarm - According to HedEx, this alarm indicates that the automatic synchronization function of the system control board is disabled. When this alarm occurs, the batch backup cannot be initiated. For this reason, the data of the working and protection boards is inconsistent.
This alarm was being displayed on the backup control board (CXP - Verison 5.76.01.33) connected on slot 08.
1. Accessing the RTN 950 by Navigator, we could see that the AutoSyncState for the board on slot 8 was DISABLE:
2. We've issued the command "hbu-set-autobatch:8:enable" in order to enable the AutoSync on the board of slot 8:
3. After issuing the command, we've checked the AutoSyncState again and confirmed that now it's enable:
4. In order to confirm that the data between the control boards now is consistent, we've issued the command "hbu-get-backup-info" and could see output as 0x00000000, when trying to issue the previous command "hbu-set-autobatch:8:enable" , we got a message saying the NE is busy, so we concluded that the data was being synchronized between the NEs. After some time, we could see the output of the "hbu-get-backup-info" as 0x00000003:
5. After this modification, the alarm has cleared and the problem resolved, confirmed by customer.
Checking the description of this alarm, we could conclude that since the primary and backup control boards were not being synchronized between each other, as soon customer has the primary board switching to the backup board, the services would be lost, since the backup board doesn't have the correct information from the primary board. The solution would be enable the synchronism between the control boards.
Suggestion to always keep the Synchronism between the boards enable, since the dual board scenario is used as redundancy, so we should always have the data consistent between the control boards to avoid interruption.