Configuring a DHCPv6 Server and Relay Agent

Context

Before powering on a device that requires automatic deployment through ZTP, deploy a DHCPv6 server from which the device can obtain a device management IP address, gateway address, intermediate file server address, and intermediate file name.

In the DHCPv6 Solicit phase, the device sends to the DHCPv6 server a DHCPv6 Solicit message that carries DHCPv6 Option 6. DHCPv6 Option 6 records the option code requested by the client.

Table 1 describes the option fields that need to be configured on the DHCPv6 server.

**Table 1** Option field description
Option	Mandatory or Optional	Function
5	Mandatory	Requested IA address, IPv6 address, and lifetime.
59	Mandatory	Path of the intermediate file. The intermediate file name extension is .ini, .py, or .cfg. The format of this field is as follows: tftp://hostname/path/filename ftp://[username[:password]@]hostname/path/filename sftp://[username[:password]@]hostname/path/filename

The IPv6 address lease that ZTP applies for through DHCPv6 is at least one hour and cannot be renewed.

If a ZTP-enabled device and DHCPv6 server reside on different network segments, deploy a DHCPv6 relay agent to forward DHCPv6 packets.

Procedure

Configure an address pool carrying Option 59 on the device that functions as a DHCPv6 server.
Configure the address pool to assign IP addresses to access users.
(Optional) Configure the DHCPv6 relay agent, if deployed. For configuration details, see Configuring DHCPv6 Relay.