Hello, friend!
The IPMB board has 32 251 channels. The 30 slots in the master shelf use 30 251 channels. The other two 251 channels communicate with the APSB control board in the slave shelf. Similarly, each APSB board has two 250 channels corresponding to the 251 channels. When a 250 channel of APSB is faulty, APSB fails to register when an IPMB is in the active state and is in the failed online state.
Because there are two APSB boards, the failure of channel 250 of one APSB board does not affect services. In addition, the APSB standby failed online problem can be avoided by switching the IPMB board. However, the final solution is to replace the board.
Thanks!