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Cisco Switch 啟用 DHCP Snooping

啟動DHCP Snooping

假設我的DHCP Server接在24 Port，其他Port不允許有DHCP Server


C3750(config)#ip dhcp snooping
C3750(config)#ip dhcp snooping vlan 1
C3750(config)#interface gigabitEthernet 2/0/24
C3750(config-if)#ip dhcp snooping trust
C3750(config-if)#do show ip dhcp snooping
Switch DHCP snooping is enabled
DHCP snooping is configured on following VLANs:
1
DHCP snooping is operational on following VLANs:
1
DHCP snooping is configured on the following L3 Interfaces:

Insertion of option 82 is enabled
   circuit-id default format: vlan-mod-port
   remote-id: 0016.9d99.3e80 (MAC)
Option 82 on untrusted port is not allowed
Verification of hwaddr field is enabled
Verification of giaddr field is enabled
DHCP snooping trust/rate is configured on the following Interfaces:

Interface                  Trusted    Allow option    Rate limit (pps)
-----------------------    -------    ------------    ----------------
GigabitEthernet2/0/24      yes        yes             unlimited
  Custom circuit-ids:

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