# Suggested DHCPv6 Client Prefix

To configure a prefix entry for a DHCPv6 client, enter the following information, then click OK:

- IAPD-ID: Enter a positive integer that identifies a certain prefix on the server. The client can use this value to request a specific prefix from the server. If you specify a nonzero Identity Association for Prefix Delegation Identifier (IAPD-ID), it maps statically to a single prefix that has the same IAPD-ID on the server. If you specify a zero IAPD-ID value or omit the value (which assigns it a zero value by default), the IAPD-ID maps it dynamically to a prefix pool on the server. The device treats all prefixes with a zero IAPD-ID as members of this pool.

- IPv6 Prefix Preference: Enter a 128-bit prefix and a 48-bit to 64-bit length.

- Preferred Lifetime: Select Permanent, or enter the period during which this entry is to be active.

If you select Permanent, the entry does not expire.

You can enter an exact period for use in the format days:hours:minute:seconds. The range for days is from 0 to 49710. The range for hours is from 0 to 24. The ranges for minutes and seconds are from 0 to 60.
Note: The device does not recognize values greater than 24 hours or 60 minutes/seconds. If you enter values greater than these limits, the device does not recognize them and generates an error message.

- Valid Lifetime (Optional): select Permanent, or enter the period for the lease. Valid lifetime must equal or exceed Preferred Lifetime or the device generates an error message.

If you select Permanent, the entry does not expire.

You can enter an exact period for use in the format days:hours:minute:seconds. The range for days is from 0 to 49710. The range for hours is from 0 to 24. The ranges for minutes and seconds are from 0 to 60.
Note: The device does not recognize values greater than 24 hours or 60 minutes/seconds. If you enter values greater than these limits, the device does not recognize them and generates an error message.