交换机 mstp导致上行端口shutdown，业务端口dis

哪位大神帮忙分析下为什么上行端口自动shutdown ，其他口discarding 

Interface 9437231 is Down, ifAdminStatus is 1, ifOperStatus is 2

H3C MSTP/4/MSTP_BPDU_FORMAT_ERROR: Port GigabitEthernet1/0/48 received MSTP BPDUs of different formats continually. Shut it down in order to prevent broadcast.

H3C IFNET/3/LINK_UPDOWN: GigabitEthernet1/0/48 link status is DOWN. 

H3C IFNET/3/LINK_UPDOWN: Vlan-interface1 link status is DOWN.

H3C IFNET/5/LINEPROTO_UPDOWN: Line protocol on the interface Vlan-interface1 is DOWN

Instance 0's Port 0.9437188 has been set to forwarding state!

Instance 0's port GigabitEthernet1/0/5 has been set to forwarding state.

。。。

H3C MSTP/6/MSTP_FORWARDING: Instance 0's port GigabitEthernet1/0/48 has been set to forwarding state. 

H3C MSTP/6/MSTP_DETECTED_TC: Instance 0's port GigabitEthernet1/0/48 detected a topology change.

<hh3cPortMstiStateDiscarding>: Instance 0's Port 0.9437205 has been set to discarding state! 

Instance 0's Port 0.9437206 has been set to discarding state!

H3C LLDP/6/LLDP_CREATE_NEIGHBOUR: New neighbor created on Port GigabitEthernet1/0/48 (IfIndex 9437231), Chassis ID is 84d9-31c7-b004, Port ID is GigabitEthernet1/0/24.

H3C S5120-52P-SI   Version 5.20, Release 1518

组网：

核心：H3C S5500-28C-SI

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1/0/48

接入：H3C S5120  

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