Chapter 25 IP Source Guard
GS1920 Series User’s Guide
208
25.5.1
DHCP Snooping Port Configure
Use this screen to specify whether ports are trusted or untrusted ports for DHCP snooping.
Note:
If DHCP snooping is enabled but there are no trusted ports, DHCP requests cannot
reach the DHCP server.
You can also specify the maximum number for DHCP packets that each port (trusted or untrusted)
can receive each second.
To open this screen, click Advanced Application > IP Source Guard >
DHCP Snooping > Configure > Port.
Figure 150
Advanced Application > IP Source Guard > DHCP Snooping > Configure > Port
Write delay interval
Enter how long (10-65535 seconds) the Switch waits to update the DHCP snooping
database the first time the current bindings change after an update. Once the next
update is scheduled, additional changes in current bindings are automatically
included in the next update.
Renew DHCP
Snooping URL
Enter the location of a DHCP snooping database, and click Renew if you want the
Switch to load it. You can use this to load dynamic bindings from a different DHCP
snooping database than the one specified in Agent URL.
When the Switch loads dynamic bindings from a DHCP snooping database, it does
not discard the current dynamic bindings first. If there is a conflict, the Switch
keeps the dynamic binding in volatile memory and updates the Binding collisions
counter in the DHCP Snooping screen
.
Apply
Click Apply to save your changes to the Switch’s run-time memory. The Switch
loses these changes if it is turned off or loses power, so use the Save link on the
top navigation panel to save your changes to the non-volatile memory when you
are done configuring.
Cancel
Click this to reset the values in this screen to their last-saved values.
Table 92
Advanced Application > IP Source Guard > DHCP Snooping > Configure
(continued)
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