Siemens S223 - Manual (Page 260)

UMN:CLI User Manual
SURPASS hiD 6615 S223/S323 R1.5
260 A50010-Y3-C150-2-7619
8.8.7.6 DHCP Snooping Database Agent
When DHCP snooping is enabled, the system uses the DHCP snooping binding database
to store information about untrusted interfaces. Each database entry (binding) has an IP
address, associated MAC address, lease time, interface to which the binding applies and
VLAN to which the interface belongs.
To maintain the binding when reload the system, you must use DHCP snooping database
agent. If the agent is not used, the DHCP snooping binding will be lost when the switch is
rebooted. The mechanism for the database agent saves the binding in a file at a remote
location. Upon reloading, the switch reads the file to build the database for the binding.
The system keeps the current file by writing to the file as the database changes.
Specifying DHCP Snooping Database Agent
To specify a DHCP database agent and enable an automatic DHCP snooping database
back-up, use the following command.
Command Mode Description
ip dhcp snooping database
A.B.C.D INTERVAL
Specifies a DHCP snooping database agent and back-
up interval.
A.B.C.D: DHCP snooping database agent address
INTERVAL: 120-2147483637 (unit: second)
no ip dhcp snooping database
Global
Deletes a specified DHCP snooping database agent.
To request snooping binding entries from a DHCP snooping database agent, use the fol-
lowing command.
Command Mode Description
ip dhcp snooping database re-
new A.B.C.D
Global
Requests snooping binding entries from a DHCP
snooping database agent.
A.B.C.D: DHCP snooping database agent address
Specifying DHCP Snooping Binding Entry
The DHCP snooping binding table contains a hardware address, IP address, lease time,
VLAN ID, and port information that correspond to the untrusted interfaces of the system.
To manually specify a DHCP snooping binding entry, use the following command.
Command Mode Description
ip dhcp snooping binding <1-
4094> PORT A.B.C.D MAC-ADDR
<120-2147483637>
Configures binding on DHCP snooping table.
1-4094: VLAN ID
PORT: port number
A.B.C.D: IP address
MAC-ADDR: MAC address
120-2147483637: lease time (unit: second)
clear ip dhcp snooping binding
PORT {A.B.C.D | all}
Global
Releases configured binding on DHCP snooping table.