Dhcp Snooping Vlan Configure - ZyXEL Communications GS1920 Series User Manual

Chapter 25 IP Source Guard
The following table describes the labels in this screen.
Table 82 Advanced Application > IP Source Guard > DHCP Snooping > Configure > Port
LABEL
Port
Server Trusted state
Rate (pps)
Apply
Cancel

25.5.2 DHCP Snooping VLAN Configure

Use this screen to enable DHCP snooping on each VLAN and to specify whether or not the Switch
adds DHCP relay agent option 82 information
Switch relays to a DHCP server for each VLAN. To open this screen, click Advanced Application >
IP Source Guard > DHCP Snooping > Configure > VLAN.
Figure 136 Advanced Application > IP Source Guard > DHCP Snooping > Configure > VLAN
194
DESCRIPTION
This field displays the port number. If you configure the * port, the settings are
applied to all of the ports.
Select whether this port is a trusted port (Trusted) or an untrusted port
(Untrusted).
Trusted ports are connected to DHCP servers or other switches, and the Switch
discards DHCP packets from trusted ports only if the rate at which DHCP packets
arrive is too high.
Untrusted ports are connected to subscribers, and the Switch discards DHCP
packets from untrusted ports in the following situations:
• The packet is a DHCP server packet (for example, OFFER, ACK, or NACK).
• The source MAC address and source IP address in the packet do not match any
of the current bindings.
• The packet is a RELEASE or DECLINE packet, and the source MAC address and
source port do not match any of the current bindings.
• The rate at which DHCP packets arrive is too high.
Specify the maximum number for DHCP packets (1-2048) that the Switch receives
from each port each second. The Switch discards any additional DHCP packets.
Enter 0 to disable this limit, which is recommended for trusted ports.
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.
Click this to reset the values in this screen to their last-saved values.
(Chapter 34 on page 264) to DHCP requests that the
GS1920 Series User's Guide