设备snmp脱管，查看设备debugging snmp有正常收发SNMP包，网管侧抓包看收发也正常
多次查看dis udp verbose，找到Creator: snmpd进程，对比Receiving buffer和Sending buffer看计数有增长，说明snmp报文有积压，怀疑是网管轮询交换机频率太高导致
Location: chassis 1 slot 6 cpu 0
Creator: snmpd[153202]
State: N/A
Options: SO_REUSEPORT
Error: 0
Receiving buffer(cc/hiwat/lowat/drop/state): 42015 / 42240 / 1 / 89310318 / N/A
Sending buffer(cc/hiwat/lowat/state): 0 / 77 / 56 / N/A
Type: 2
Protocol: 17
Connection info: Src = 0.0.0.0:161, Dst = 0.0.0.0:0
Inpcb flags: INP_RECVDSTADDR INP_REUSEPORT INP_SYNCPCB
Inpcb extflag: N/A
Inpcb vflag: INP_IPV4
TTL: 255(minimum TTL: 0)
Send VRF: 0xffff
Receive VRF: 0xffff
降低网管访问交换机频率