DHCPv6 Behaviour in Windows Vista

re: DHCPv6 Behaviour in Windows Vista

norman — Thu, 31 Dec 2009 02:24:59 GMT

Hi all

I try to use dhcpv6 server (stateless)in windows 2008 r2 with windows vista.

But I find something differences

1.when I use vista without any service pack ,then I can ping to server ,check routing table ,vista will add a routing for dhcpv6 prefix.

2.when I use vista with sp2 or windows 7

ping to server will fail, because client will not add a routing for me

is this a bug for client ?

re: DHCPv6 Behaviour in Windows Vista

teamdhcp — Fri, 31 Jul 2009 14:05:04 GMT

Since DHCP client uses Windows LLT-DUID, In order to change the DUID, deleting it will help. New DUID will be generated when any media is connected or enabled after that on the machine.

re: DHCPv6 Behaviour in Windows Vista

JohnG — Fri, 31 Jul 2009 13:41:30 GMT

We have discovered a number of Vista machines with Identical DUIDs. Presumably they are the result of some sort of cloning/imaging.

How can we change the DUID on these machines? Can we simply delete the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters\Dhcpv6DUID value?

re: DHCPv6 Behaviour in Windows Vista

teamdhcp — Tue, 12 May 2009 13:35:51 GMT

So the DHCPv6 Server in WS08 does not identify Remote-Identifier(37) option, and hence it is dropping the packet. The issue is resolved in WS08 R2. Please try to disable the Cisco Relay from sending the remote-id option.

re: DHCPv6 Behaviour in Windows Vista

teamdhcp — Tue, 12 May 2009 13:30:42 GMT

The Windows DHCP server does NOT listen to the Link Local address of the link.

The DHCP server only listens to the bound global unicast address and the DHCP Server related multicast addresses in the links.

Can you verify if the DHCP server IP address configured in the relay agent is the Global address which the DHCP server is bound to?

If yes, Can you send the packet(s) capture from the relay agent to the server?

re: DHCPv6 Behaviour in Windows Vista

mii — Tue, 12 May 2009 13:26:47 GMT

Thanks for replying,

The original message from vista pc, contains Elapsed-Time(8)/Client-Identifier(1)/Vendor-Class(16)/Option-Request(6) options, are encapsulated in Relay-Message(9) option.

Plus, Interface-Identifier(18) and Remote-Identifier(37) options are added by cisco relay.

re: DHCPv6 Behaviour in Windows Vista

teamdhcp — Tue, 12 May 2009 12:54:34 GMT

There is no configuration required on the DHCP Server in environments where we have DHCP relays.

What are the DHCP options being added by the Cisco Relays ?

Windows DHCPv6 server does not respond to relayed messages

mii — Tue, 12 May 2009 12:34:40 GMT

Hello team,

Is there any specific configuration for Windows 2008 DHCPv6 server to respond to relayed requests ?

I have 2 networks connected with cisco sw. There are Windows 2008 DHCPv6 server and Vista PC on the each side. Cisco relays DHCPv6 messages to/from the server.

Windows 2008 server is configured as stateless dhcpv6 server to provide dns servers and domain information. It does not have any ipv6 scopes.

When the vista is connected to the network, the server receives relayed "information-request" message (at least captures on the server). However, the server does not respond.

If the vista and server is on the same segment, vista can be configured perfectly.

Thank you,

re: DHCPv6 Behaviour in Windows Vista

teamdhcp — Thu, 02 Apr 2009 17:13:40 GMT

DUID is generated only once for a machine. It is global across all adapters. In Vista, Duid is generated on the first adapter connect. It is persistent after that.

re: DHCPv6 Behaviour in Windows Vista

teamdhcp — Tue, 31 Mar 2009 13:29:02 GMT

The Duid is present in following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters\Dhcpv6DUID.

By the way in which captures are you seeing for "DUID". All Dhcpv6 packets transmitted by client would have Duid in "ClientID" option.

Thanks

teamdhcp