Deployment Guide

DHCP [On]:off
Example of disabling DHCP for IPv4 using a single command:
switch:admin> ipaddrset -ipv4 -add -dhcp OFF
switch:admin> ipaddrshow
SWITCH
Ethernet IP Address: 10.20.134.219
Ethernet Subnetmask: 255.255.240.0
Gateway IP Address: 10.20.128.1
DHCP: Off
IPv6 autoconfiguration
IPv6 can assign multiple IP addresses to each network interface. Each interface is configured with a
link local address in almost all cases, but this address is only accessible from other hosts on the same
network. To provide for wider accessibility, interfaces are typically configured with at least one
additional global scope IPv6 address. IPv6 autoconfiguration allows more IPv6 addresses, the number
of which is dependent on the number of routers serving the local network and the number of prefixes
they advertise.
There are two methods of autoconfiguration for IPv6 addresses: stateless autoconfiguration and
stateful autoconfiguration. Stateless autoconfiguration allows an IPv6 host to obtain a unique address
using the IEEE 802 MAC address. Stateful autoconfiguration uses a DHCPv6 server, which keeps a
record of the IP address and other configuration information for the host. Whether a host engages in
autoconfiguration and which method it uses is dictated by the routers serving the local network, not by
a configuration of the host. There can be multiple routers serving the network, each potentially
advertising multiple network prefixes. Thus, the host is not in full control of the number of IPv6
addresses that it configures, much less the values of those addresses, and the number and values of
addresses can change as routers are added to or removed from the network.
When IPv6 autoconfiguration is enabled, the platform engages in stateless IPv6 autoconfiguration.
When IPv6 autoconfiguration is disabled, the platform relinquishes usage of any autoconfigured IPv6
addresses that it may have acquired while it was enabled. This same enable or disable state also
enables or disables the usage of a link local address for each managed entity, though a link local
address continues to be generated for each nonchassis-based platform and for each CP of a chassis-
based platform because those link local addresses are required for router discovery. The enabled or
disabled state of autoconfiguration is independent of whether any static IPv6 addresses have been
configured.
Setting IPv6 autoconfiguration
Use the following procedure to enable IPv6 autoconfiguration:
1. Connect to the switch and log in using an account with admin permissions.
2. Take the appropriate following action based on whether you want to enable or disable IPv6
autoconfiguration:
• Enter the ipAddrSet -ipv6 -auto command to enable IPv6 autoconfiguration for all managed
entities on the target platform.
• Enter the ipAddrSet -ipv6 -noauto command to disable IPv6 autoconfiguration for all managed
entities on the target platform.
IPv6 autoconfiguration
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