3）使能攻击溯源功能（默认使能），通过display auto-defend configuration命令确认配置，“auto-defend”字段显示“enable”。
[CSS] display auto-defend configuration
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Name : default
Related slot : <1/7-1/8,2/7-2/8,1/9>
auto-defend : enable
auto-defend attack-packet sample : 5
auto-defend threshold : 60 (pps)
auto-defend trace-type : source-mac source-ip
auto-defend protocol : arp icmp dhcp igmp tcp telnet 8021x nd dhcpv6 mld icmpv6
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