Enabling DHCPv6 Relay Agent Prefix Delegation Notification on an interface

The number of delegated prefixes that can be learned can be limited at the interface level.

Enter global configuration mode by issuing the configure terminal command.
```
device# configure terminal
```

Enter interface configuration mode.

device(config)# interface ethernet 1/1/1

Set the number of delegated prefixes that can be learned.
```
device(config-if-eth 1/1/1)# ipv6 dhcp-relay maximum-delegated-prefixes 100
```
You can limit the maximum number of prefixes that can be delegated. The range is from 0 through 512. The default value is 100. The sum of all the delegated prefixes that can be learned at the interface level is limited by the system max.

The following example sets the number of delegated prefixes that can be learned to 100.

device# configure terminal
device(config)# interface ethernet 1/1/1
device(config-if-eth 1/1/1)# ipv6 dhcp-relay maximum-delegated-prefixes 100