SMC Networks 7724M/VSW - annexe 1, Manual

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Management Guide CLI
TigerAccess™ EE
SMC7824M/VSW 325
To discard broadcast request packets of Egress traffic on specified trusted port, use the
following command.
Command Mode Description
ip dhcp snooping trust PORTS
filter egress bcast-req
Blocks broadcast request packets of Egress traffic on
specified trusted port.
no ip dhcp snooping trust
PORTS filter egress bcast-req
Global
Unblocks broadcast request packets of Egress traffic
on specified trusted port.
8.6.7.3 DHCP Rate Limit
To set the number of DHCP packets per second (pps) that an interface can receive, use
the following command.
Command Mode Description
ip dhcp snooping limit-rate
PORTS <1-255>
Sets a rate limit for DHCP packets. (unit: pps)
no ip dhcp snooping limit-rate
PORTS
Global
Deletes a rate limit for DHCP packets.
Normally, the DHCP rate limit is specified to untrusted interfaces and 15 pps is recom-
mended for a proper value. However, if you want to set a rate limit for trusted interfaces,
keep in mind that trusted interfaces aggregate all DHCP traffic in the switch, and you will
need to adjust the rate limit to a higher value.
8.6.7.4 DHCP Lease Limit
The number of entry registrations in DHCP snooping binding table can be limited. If there
are too many DHCP clients on an interface and they request IP address at the same time,
it may cause IP pool exhaustion.
To set the number of entry registrations in DHCP snooping binding table, use the follow-
ing command.
Command Mode Description
ip dhcp snooping limit-lease
PORTS <1-2147483637>
Enables a DHCP lease limit on a specified untrusted
port.
1-2147483637: the number of entry registrations
no ip dhcp snooping limit-lease
PORTS
Global
Deletes a DHCP lease limit.
You can limit the number of entry registrations only for untrusted interfaces, because the
DHCP snooping binding table only contains the information for DHCP messages from un-
trusted interfaces.
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