Alcatel-Lucent 7750 SR OS Service Manual page 989

Description
This command enables dynamic host lease state management for VPLS SAPs and VPRN or IES IP
interfaces. Lease state information is extracted from snooped or relayed DHCP ACK messages to
populate lease state table entries for the SAP or IP interface.
The optional number-of-entries parameter defines the number lease state table entries allowed for this
SAP or IP interface. If number-of-entries is not specified, only a single entry is allowed. Once the
maximum number of entries has been reached, subsequent lease state entries are not allowed. If lease
state population is enabled and an entry cannot be retained in the table, the DHCP Relay or DHCP
snoop function will prevent the far-end host from receiving the DHCP ACK message.
The retained lease state information representing dynamic hosts may be used to populate a SAP based
anti-spoof filter table to provide dynamic anti-spoof filtering. Anti-spoof filtering is only available on
VPLS SAPs, IES IP interfaces terminated on a SAP or VPRN IP interfaces terminated on a SAP.
The retained lease state information representing dynamic hosts may be used to populate the system's
ARP cache based the arp-populate feature. ARP-populate functionality is only available for static and
dynamic hosts associated with IES and VPRN SAP bound IP interfaces.
The retained lease state information representing dynamic hosts may be used to populate managed
entries into a VPLS forwarding database. VPLS forwarding database population is an implicit feature
that automatically places the dynamic host's MAC address into the VPLS FDB. When a dynamic
host's MAC address is placed in the lease state table, it will automatically be populated into the VPLS
forwarding database associated with the SAP on which the host is learned. The dynamic host MAC
address will override any static MAC entries using the same MAC and prevent dynamic learning of
the MAC on another interface. Existing static MAC entries with the same MAC address as the
dynamic host are marked as inactive but not deleted. If all entries in the lease state table associated
with the MAC address are removed, the static MAC may be populated. New static MAC definitions
for the VPLS instance may be created while a dynamic host exists associated with the static MAC
address.
Default
not enabled
Parameters
nbr-of-entries — Defines the number lease state table entries allowed for this interface. If this
match-circuit-id
Syntax [no] match-circuit-id
Context config>service>vprn>sub-if>grp-if>dhcp
Description
This command enables Option 82 circuit ID on relayed DHCP packet matching.
For Routed CO, the group interface DHCP relay process is stateful. When packets are relayed to the
server the virtual router ID, transaction ID, SAP ID, and client hardware MAC address of the relayed
packet are tracked. When we get a response back from the server the virtual router ID, transaction ID,
and client HW MAC address must be matched to determine the SAP on which to send the packet out.
In some cases, the virtual router ID, transaction ID, and client HW MAC address are not guaranteed
to be unique.
7750 SR OS Services Guide
parameter is omitted, only a single entry is allowed. Once the maximum number of entries has
been reached, subsequent lease state entries are not allowed and subsequent DHCP ACK
messages are discarded.
Values
1 — 8000
Virtual Private Routed Network Services
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