IP Configuration
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Instruction Manual - NXA-ENET8-POE+
ND DAD Attempts
The number of consecutive neighbor solicitation messages sent on an interface during duplicate
address detection. (Range: 0-600, Default: 3)
• Configuring a value of 0 disables duplicate address detection.
• Duplicate address detection determines if a new unicast IPv6 address already exists on the
network before it is assigned to an interface.
• Duplicate address detection is stopped on any interface that has been suspended (see the
section on page 88). While an interface is suspended, all unicast IPv6
addresses assigned to that interface are placed in a pending state. Duplicate address detection
is automatically restarted when the interface is administratively re-activated.
• An interface that is re-activated restarts duplicate address detection for all unicast IPv6
addresses on the interface. While duplicate address detection is performed on the interface's
link-local address, the other IPv6 addresses remain in a tentative state. If no duplicate link-local
address is found, duplicate address detection is started for the remaining IPv6 addresses.
• If a duplicate address is detected, it is set to duplicate state, and a warning message is sent to
the console. If a duplicate link-local address is detected, IPv6 processes are disabled on the
interface. If a duplicate global unicast address is detected, it is not used. All configuration
commands associated with a duplicate address remain configured while the address is in
duplicate state.
• If the link-local address for an interface is changed, duplicate address detection is performed on
the new link-local address, but not for any of the IPv6 global unicast addresses already
associated with the interface.
ND NS Interval
The interval between transmitting IPv6 neighbor solicitation messages on an interface. (Range:
1000-3600000 milliseconds)
Default: 1000 milliseconds is used for neighbor discovery operations, 0 milliseconds is advertised
in router advertisements.
This attribute specifies the interval between transmitting neighbor solicitation messages when
resolving an address, or when probing the reachability of a neighbor. Therefore, avoid using very
short intervals for normal IPv6 operations.
When a non-default value is configured, the specified interval is used both for router
advertisements and by the router itself.
ND Reachable-Time
The amount of time that a remote IPv6 node is considered reachable after some reachability
confirmation event has occurred. (Range: 0-3600000 milliseconds)
Default: 30000 milliseconds is used for neighbor discovery operations, 0 milliseconds is advertised
in router advertisements.
• The time limit configured by this parameter allows the router to detect unavailable neighbors.
During the neighbor discover process, an IPv6 node will multicast neighbor solicitation
messages to search for neighbor nodes. For a neighbor node to be considered reachable, it must
respond to the neighbor soliciting node with a neighbor advertisement message to become a
confirmed neighbor, after which the reachable timer will be considered in effect for subsequent
unicast IPv6 layer communications.
• This time limit is included in all router advertisements sent out through an interface, ensuring
that nodes on the same link use the same time value.
• Setting the time limit to 0 means that the configured time is unspecified by this router.
Restart DHCPv6
When DHCPv6 is restarted, the switch may attempt to acquire an IP address prefix through stateful
address auto-configuration. If the router advertisements have the
other stateful configuration
flag
set, the switch may also attempt to acquire other non-address configuration information (such as
a default gateway) when DHCPv6 is restarted.
Prior to submitting a client request to a DHCPv6 server, the switch should be configured with a link-
local address using the Address Autoconfig option. The state of the Managed Address
Configuration flag (M flag) and Other Stateful Configuration flag (O flag) received in Router
Advertisement messages will determine the information this switch should attempt to acquire from
the DHCPv6 server as described below.
• Both M and O flags are set to 1:
DHCPv6 is used for both address and other configuration settings.
This combination is known as DHCPv6 stateful auto-configuration, in which a DHCPv6 server
assigns stateful addresses to IPv6 hosts.
• The M flag is set to 0, and the O flag is set to 1: DHCPv6 is used only for other configuration
settings.
Neighboring routers are configured to advertise non-link-local address prefixes from which IPv6
hosts derive stateless addresses.
This combination is known as DHCPv6 stateless auto-configuration, in which a DHCPv6 server
does not assign stateful addresses to IPv6 hosts, but does assign stateless configuration
settings.
System - IPv6 Configuration Options