Chapter 6 Tutorials
GS1920 Series User’s Guide
47
6
The DHCP Snooping Port Configure screen appears. Select Trusted in the Server Trusted
state field for port 5 because the DHCP server is connected to port 5. Keep ports 6 and 7
Untrusted because they are connected to DHCP clients. Click Apply.
Figure 33
Tutorial: Set the DHCP Server Port to Trusted
7
Go to Advanced Application > IP Source Guard > DHCP snooping > Configure > VLAN,
show VLAN 100 by entering 100 in the Start VID and End VID fields and click Apply. Then select
Yes in the Enabled field of the VLAN 100 entry shown at the bottom section of the screen.
If you want to add more information in the DHCP request packets such as source VLAN ID or
system name, you can also select the Option82 Profile field in the entry. See Section 25.10.1.3
on page 220.
Figure 34
Tutorial: Enable DHCP Snooping on this VLAN
8
Click Save at the top right corner of the web configurator to save
the configuration permanently.
9
Connect your DHCP server to port 5 and a computer (as DHCP client) to either port 6 or 7. The
computer should be able to get an IP address from the DHCP server. If you put the DHCP server on
port 6 or 7, the computer will not able to get an IP address.
10
To check if DHCP snooping works, go to Advanced Application > IP Source Guard, you should
see an IP assignment with the type DHCP-Snooping as shown.
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