Use the following procedure to configure DHCP snooping globally on the switch.
From the navigation tree, double-click Security.
In the Security tree, double-click DHCP Snooping.
In the work area, click the DHCP Snooping Globals tab.
To enable DHCP snooping globally, click the DhcpSnoopingEnabled box.
To enable Option 82 for DHCP snooping, click the DhcpSnoopingOption82Enabled box.
On the toolbar, click Apply.
You must enable DHCP snooping on Layer 3 VLANs spanning toward DHCP servers in Layer 3 mode. DHCP relay is also required for correct operation.
The following table describes the fields of DHCP Snooping Globals tab.
Variable | Value |
---|---|
DhcpSnoopingEnabled | Enables or disables DHCP Snooping globally. |
DhcpSnoopingOption82Enabled | Enables or disables DHCP Snooping option 82 globally. |
Use this procedure to store the DHCP Snooping database to an external TFTP server or USB drive.
From the navigation tree, double-click Security.
In the Security tree, click DHCP Snooping.
In the work area, click the DHCP Snooping Globals tab.
In the DHCP Snooping External Save section, select the Enabled checkbox, to enable DHCP Snooping external save.
OR
In the DHCP Snooping External Save section, clear the Enabled checkbox, to disable DHCP Snooping external save.
Click a TftpServerAddressType button.
Type a value in the TftpServerAddress box.
Type a value in the UsbTargetUnit box.
Type a value in the Filename box.
To force a binding table restore, click the ForceRestore button.
On the toolbar, click Apply.
Variable | Value |
---|---|
DHCP Snooping External Save | |
Enabled | Enables or disables DHCP Snooping External Save. |
SyncFlag | Indicates if changes in the DHCP Snooping binding table are synchronized on the external device. Values include:
|
LastSyncTime | Displays the UTC time when the switch last backed up the DHCP Snooping binding table. |
TftpServerAddressType | Specifies the IP address type of the TFTP server on which to save the DHCP Snooping binding file. Values include ipv4 or ipv6. |
TftpServerAddress | Specifies the IPv4 or IPv6 address of the TFTP server on which to save the DHCP Snooping binding file. |
UsbTargetUnit | Specifies the unit number of the USB port to use in file save or restore operations. |
Filename | Specifies the name of the DHCP Snooping database that is saved externally. |
ForceRestore | Forces the restoration of the DHCP Snooping database on the switch from the file previously saved to an external USB drive or TFTP server. |