Web Management Guide-R04

Table Of Contents
Chapter 16
| IP Configuration
Setting the Switch’s IP Address (IP Version 6)
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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 switch.
Restart DHCPv6 – When DHCPv6 is restarted, the switch may attempt to
acquire an IP address prefix through stateful address autoconfiguration. 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 autoconfiguration, 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 autoconfiguration, in
which a DHCPv6 server does not assign stateful addresses to IPv6 hosts, but
does assign stateless configuration settings.
RA Guard
Interface – Shows port or trunk configuration page.
RA Guard – Blocks incoming Router Advertisement and Router Redirect
packets. (Default: Disabled)
IPv6 Router Advertisements (RA) convey information that enables nodes to
auto-configure on the network. This information may include the default router
address taken from the observed source address of the RA message, as well as
on-link prefix information. However, note that unintended misconfigurations,
or possibly malicious attacks on the network, may lead to bogus RAs being
sent, which in turn can cause operational problems for hosts on the network.
RA Guard can be used to block RAs and Router Redirect (RR) messages on the
specified interface. Determine which interfaces are connected to known
routers, and enable RA Guard on all other untrusted interfaces.