Dynamic Data Persistency (Ddp) Access Optimization For Dhcp Leases - Alcatel-Lucent 7450 Basic System Configuration Manual

Synchronization and Redundancy
Dynamic Data Persistency (DDP) Access Optimization for DHCP
Leases
A high rate of DHCP renewals can create a load on the compact flash file system when
subscriber management and/or DHCP server persistence is enabled. To optimize the access
to the Dynamic Data Persistency (DDP) files on the compact flash, a lease-time threshold can
be specified that controls the eligibility of a DHCP lease for persistency updates when no
other data other than the lease expiry time is to be updated.
configure
[min <minutes>] [sec <seconds>]
When the offered lease time of the DHCP lease is less than the configured threshold, the lease
is flagged to skip persistency updates and will be installed with its full lease time upon a
persistency recovery after a reboot.
The dhcp-leasetime-threshold command controls persistency updates for:
To check if a DHCP relay or proxy lease is flagged to skip persistency updates, use the tools
dump persistence submgt record record-key CLI command. When flagged to skip
persistency updates, the persistency record output will include "Skip Persistency Updates:
true".
250
system
persistence
subscriber-mgmt
location cf2:
exit
dhcp-server
location cf2:
exit
options
dhcp-leasetime-threshold [days <days>] [hrs <hours>]
exit
exit
exit
• DHCPv4 and DHCPv6 leases for a DHCP relay or proxy (enabled with persistence
subscriber-mgmt)
• DHCPv4 leases for DHCP snooping in a VPLS service (enabled with persistence
subscriber-mgmt)
• DHCPv4 and DHCPv6 leases for a DHCP server (enabled with persistence dhcp-
server)
Basic System Configuration Guide