Show ipv6 dhcp duid – Brocade 6910 Ethernet Access Switch Configuration Guide (Supporting R2.2.0.0) User Manual
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Brocade 6910 Ethernet Access Switch Configuration Guide
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DHCP Client
Command Mode
Privileged Exec
Command Usage
•
This command starts the DHCPv6 client process if it is not yet running by submitting requests
for configuration information through the specified interface(s). 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 or DNS server) 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
command. 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, 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, in which a DHCPv6 server does not
assign stateful addresses to IPv6 hosts, but does assign stateless configuration settings.
•
DHCPv6 clients build a list of servers by sending a solicit message and collecting advertised
message replies. These servers are then ranked based on their advertised preference value. If
the client needs to acquire prefixes from servers, only servers that have advertised prefixes are
considered.
•
If the rapid commit option has been enabled on the switch using the
command, and on the DHCPv6 server, message exchange can be reduced
from the normal four step process to a two-step exchange of only solicit and reply messages.
Example
The following command submits a client request on VLAN 1.
Console#ipv6 dhcp restart client vlan 1
Console#
Related Commands
show ipv6 dhcp duid
This command shows the DHCP Unique Identifier for this switch.
Command Mode
Privileged Exec