Usage Scenario
On a device from which DHCPv6 users go online in IPoE mode, the IP addresses and prefixes are delivered by the RADIUS server or assigned from local address pools or delegation address pools.Before upgrading the device, run the dhcpv6 upgrade command to modify leases of these users to a shorter period, so that DHCPv6 users can go online by sending Renew packets after the upgraded device is restarted.
After the dhcpv6 upgrade command is run, you can run the
display dhcpv6 upgrade command to view the configuration result and calculate the restart time of the
NetEngine 8000 F based on the previous lease.
This command applies to both Layer 2 and Layer 3 DHCPv6 users.
The preferred-lifetime and valid-lifetime should be configured no smaller than 30 minutes, renew-time and rebind-time must be greater than or equal to 15 minutes.
Configuration Impact
After the dhcpv6 upgrade command is run, all DHCP users use the globally configured lease, no matter whether their IP addresses and prefixes are delivered by the RADIUS server or assigned from local address pools and delegation address pools.
If a short lease is configured, CPU usage will rise when many DHCP users send renewal messages at the same time.
Follow-up Procedure
After the dhcpv6 upgrade command is run, you can run the display dhcpv6 upgrade command to view the configuration result and calculate the restart time of the NetEngine 8000 F based on the previous lease.
Precautions
In a non-BRAS-upgrade scenario, do not configure a short address lease.