preferred-lifetime (DHCPv6)

Specifies the length of time that the DHCPv6 server keeps the IPv6 prefix active.
Syntax
preferred-lifetime interval
Command Default

The preferred lifetime interval is 0 seconds by default.

Parameters
interval
Specifies the time interval in seconds. Valid values range from 0 through 4294967295. The default is 0.
Modes

DHCPv6 server configuration mode

DHCPv6 subnet configuration mode

Usage Guidelines

To use this command, you must upgrade to FastIron 08.0.90 using the Unified FastIron Image (UFI). Refer to the “Software Upgrade and Downgrade” chapter in the RUCKUS FastIron Software Upgrade Guide for more information.

Once the configured time interval expires, the IPv6 prefix is deprecated. The preferred lifetime interval must be less than or equal to the valid lifetime interval. Refer to the valid-lifetime command for more information.

When configuring the DHCPv6 server using this command along with the valid-lifetime (DHCPv6), renewal-time (DHCPv6), and rebind-time (DHCPv6) commands, enter the commands in the following order:

  1. preferred-lifetime (DHCPv6)
  2. valid-lifetime (DHCPv6)
  3. rebind-time (DHCPv6)
  4. renewal-time (DHCPv6)
Note: Failure to enter the commands in the order outlined previously when configuring the DHCPv6 server results in a CLI error.

If a preferred lifetime is not configured in DHCPv6 subnet configuration mode, the globally configured preferred lifetime is inherited.

The no form of the command restores the default.

Examples

The following example sets the preferred lifetime to 200 seconds. 

device# configure terminal
device(config)# ipv6 dhcp6-server enable
device(config-dhcp6)# preferred-lifetime 200

The following example sets the preferred lifetime to 100 seconds in DHCPv6 subnet configuration mode. 

device# configure terminal
device(config)# ipv6 dhcp6-server enable
device(config-dhcp6)# subnet6 3ffe:501:ffff:100::/64
device(config-dhcpv6-subnet)# preferred-lifetime 100
History
Release version Command history
08.0.90 This command was introduced.

Related commands:

valid-lifetime (DHCPv6)
Parent topic: Commands O, P, Q, R, and Sa through Sh