ZyXEL VES1724-56B2 User Guide - Page 258

Advanced Application > IP Source Guard, > DHCP Snooping > Con

Page 258 highlights

Chapter 26 IP Source Guard still available after a restart. To open this screen, click Advanced Application > IP Source Guard > DHCP Snooping > Configure. Figure 152 DHCP Snooping Configure The following table describes the labels in this screen. Table 113 DHCP Snooping Configure LABEL Active DESCRIPTION Select this to enable DHCP snooping on the Switch. You still have to enable DHCP snooping on specific VLAN and specify trusted ports. DHCP Vlan Note: If DHCP is enabled and there are no trusted ports, DHCP requests will not succeed. Select a VLAN ID if you want the Switch to forward DHCP packets to DHCP servers on a specific VLAN. Database Agent URL Timeout interval Note: You have to enable DHCP snooping on the DHCP VLAN too. You can enable Option82 in the DHCP Snooping VLAN Configure screen (Section 26.5.2 on page 260) to help the DHCP servers distinguish between DHCP requests from different VLAN. Select Disable if you do not want the Switch to forward DHCP packets to a specific VLAN. 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 Switch waits to start the next update until it completes the current one. 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. Enter how long (10-65535 seconds) the Switch tries to complete a specific update in the DHCP snooping database before it gives up. 258 VES1724-56 User's Guide

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Chapter 26 IP Source Guard
VES1724-56 User’s Guide
258
still available after a restart. To open this screen, click
Advanced Application > IP Source Guard
> DHCP Snooping > Configure
.
Figure 152
DHCP Snooping Configure
The following table describes the labels in this screen.
Table 113
DHCP Snooping Configure
LABEL
DESCRIPTION
Active
Select this to enable DHCP snooping on the Switch. 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 Switch 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 26.5.2
on page 260
) to help the DHCP servers distinguish between DHCP requests from different
VLAN.
Select
Disable
if you do not want the Switch 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 Switch 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,
.
Timeout
interval
Enter how long (10-65535 seconds) the Switch tries to complete a specific update in the
DHCP snooping database before it gives up.