ZyXEL Communications OLT2406, User Manual

Page: 231 / 766

Chapter 27 IP Source Guard
OLT2406 User’s Guide
231
Figure 136 Advanced Application > IP Source Guard > DHCP Snooping > Configure
The following table describes the labels in this screen.
Table 84 Advanced Application > IP Source Guard > DHCP Snooping > Configure
LABEL DESCRIPTION
Active Select this to enable DHCP snooping on the OLT. You still have to enable DHCP
snooping on specific VLAN and specify trusted ports.
Note: If DHCP is enabled and there are no trusted ports, DHCP requests will
not succeed.
DHCP Vlan Select a VLAN ID if you want the OLT to forward DHCP packets to DHCP servers on a
specific VLAN.
Note: You have to enable DHCP snooping on the DHCP VLAN too.
You can enable Option82 in the DHCP Snooping VLAN Configure screen ( Section 27.5.2
on page 233 ) to help the DHCP servers distinguish between DHCP requests from
different VLAN.
Select Disable if you do not want the OLT to forward DHCP packets to a specific VLAN.
Database If Timeout interval is greater than Write delay interval , it is possible that the next update
is scheduled to occur before the current update has finished successfully or timed out.
In this case, the OLT waits to start the next update until it completes the current one.
Agent URL Enter the location of the DHCP snooping database. The location should be expressed
like this:
tftp://{domain name or IP address}/directory, if applicable/file name ; for
example, tftp://192.168.10.1/database.txt .
Timeout interval Enter how long (10-65535 seconds) the OLT tries to complete a specific update in the
DHCP snooping database before it gives up.
Write delay interval Enter how long (10-65535 seconds) the OLT 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.