Technical References

Enables the lease history database for DHCPv4, DHCPv6, or both.
0 disabled No lease history is recorded. Default.
1 v4-only The server records lease history for DHCPv4
leases only.
2 v6-only The server records lease history for DHCPv6
leases only.
3 both The server records lease history for both
DHCPv4 and DHCPv6 leases.
ip-history-detail bool default = false
Controls whether to record detailed data for the IP
history database. Default is false (disable).
Note: Detail lease history is not available for DHCPv6.
ip-history-max-age time default = 4w
If ip-history is enabled, determines how long IP records are
kept in the database. Default is 4w.
The server accumulates database records over time as lease
bindings change. The ip-history-max-age attribute establishes
a limit on the age of thehistory records kept in the database.
The server periodically examines the lease history records,
establishes an age threshold based on this parameter, and
deletes any records that represent bindings that end before
the threshold. The history records are trimmed by default once
a day, at 3:00 a.m. local time.
last-transaction-time-granularity time default = 1w
Sets the time, in seconds, to guarantee how accurate to keep the
last transaction time (in the lease DB) when the lease is not
otherwise being written to the lease DB. Default is 1 week.
Do not set this lower than 60 seconds. For optimal performance,
set it to a value that is greater than half of your lease time.
The server can maintain an accurate record of the time it last
interacted with a DHCP client concerning a given lease. This
setting provides the control over how accurate that time is
guaranteed to be. A setting of 300 seconds, for instance, would
allow the server to avoid database updates whose sole purpose is
to update a last transaction time that is less than 5 minutes in
the past.
Note: This attribute is not used if defer-lease-extensions is
disabled.
ldap-mode enumint(round-robin=1, failover=2)
Determines the preference for using LDAP servers if
multiple LDAP servers are configured. No default.
This attribute has two possible values:
1 round-robin-The DHCP server ignores LDAP server
preferences. It treats all LDAP servers (those configured
to handle client queries and those configured to accept
lease-state updates) equally.
2 failover-The DHCP server uses the active LDAP server with
the lowest preference. If the preferred server loses its
connection or fails, the DHCP server uses the next LDAP
server in preference order. The DHCP server uses servers
with equal preference in round-robin order.