Windows server 2012 dhcp server ipv6

The Need for DHCP

Network administrators cannot expect
end users and even IT personnel to be able to manually configure each
network device’s IP address settings. Furthermore, many end users may
not even have the permissions to change network configurations. Because
of these and other challenges, DHCP services are
required on most networks to enable network connectivity. Also, many
devices do not provide an interface simple enough or readily available
to configure network settings. DHCP provides a simple way to not only
deliver IP addressing from a central administrative point, but it also
allows the network administrators to control how these devices actually
connect to the network and greatly enhance the management of these
network-connected devices through this service.

Outlining DHCP Predecessors: RARP and BOOTP

Before the DHCP service was developed, two
predecessors provided the first implementations of automated IP
addressing. The first was the Reverse Address Resolution Protocol
(RARP), and the second was the Bootstrap Protocol (BOOTP).

To understand RARP, an IT administrator
should first understand the Address Resolution Protocol (ARP). Each
network adapter, wired or wireless, has a unique address burned into
it. This address never changes and it called the Media Access Control
(MAC) address. The ARP stores IP address-to-MAC address information.
For example, if you know the IP address of a system on the network, the
ARP table will provide the corresponding MAC address associated with
that IP address. On most systems and network devices, the ARP table is
built dynamically based on previous and current connections, but only
for systems on the same network segment. RARP tables, however, are the
reverse in both the fact that they are not dynamically built and they
are MAC-to-IP resolution.

The RARP service allows a newly connected
system to broadcast its MAC address on the network and the RARP service
will respond with the assigned IP address. This allows the new system
to basically connect dynamically to the network. A few catches exist,
however. The first catch is that the RARP administrator must first
collect that new system’s MAC address and create an entry on the RARP
table on the service with a corresponding IP address. The next catch is
that RARP delivers a system an IP address but no other networking
information, such as a subnet mask, router IP address, or DNS server or
other networking options. The RARP service was limited to usage on a
single flat network, but was useful in its time.

The next predecessor is the BOOTP service.
The BOOTP service provided an IP address to clients requesting one, but
did not require a predefined table of related MAC and IP addresses.
BOOTP was designed to not only get a system connected, but to also
provide additional information to systems looking to load or boot an
operating system stored on the network. BOOTP is still used today for
some network boot implementations but has been superseded by the DHCP
service.

Examining the DHCP Client Service

The DHCP client service is the client-side
service that requests an IP address from the network. Depending on the
system’s network adapter configuration, the DHCP client service may be
active or inactive and, if the client is leveraging network boot, can
come in the form of a BOOTP or PXE client controlled by the system
board. The Windows DHCP client service, however, is managed by the
configuration stored within the Microsoft operating system and,
furthermore, on each adapter. If the adapter senses a network
connection and the IP address configuration is configured for automated
IP addressing, the DHCP client service broadcasts the request for an IP
address, and when the data is received from the server, the DHCP client
service applies the lease information to the appropriate adapter and
enables network communications. With the DHCP IP address lease, there
is an important piece of information delivered, known as the lease
duration. The lease duration informs the client how long the IP address
can be used before the client must check back with the DHCP server to
renew the lease or get a new lease. The DHCP client caches this
information, and when the lease duration is nearly up or when the
system is restarted or the network is reinitialized, the DHCP client
contacts the DHCP server to ensure the lease can still be used so that
it can be renewed or replaced with a new lease.

In addition, on Microsoft systems,
the DHCP client service also manages the Dynamic DNS registration of
the client if there is a Dynamic DNS server available. This is true
unless the DHCP server service is mandating that DHCP leases have their
dynamic DNS registration handled by the server itself.

Exploring the DHCP Server Service

The DHCP server service is the latest
implementation of automated network addressing in use today. The DHCP
server service can provide all the same functionality of a BOOTP
service, but can also provide additional information to clients who are
requesting an IP address. The DHCP server service provides a client an
IP address in three steps:

1. DHCP client boots and broadcasts a DHCP IP request to all nodes on the local network.

2.
A DHCP server on the local network receives the request and prepares to
distribute an IP address to this client in the form of a DHCP IP
address lease.

3. After the DHCP
server has determined the right prerequisite information from that
client request, it issues the client with a DHCP IP address lease,
including additional DHCP lease options such as subnet mask, default
gateway, and most likely, DNS server IP addresses.

Setting Up Windows Server 2012 DHCP IPv6 Scopes

To support stateful IPv6 with DHCP, the network administrator can create IPv6 DHCP scopes on a Windows Server 2012 DHCP server. To create a new IPv6 DHCP scope, follow these steps:

1. Open the DHCP console and connect to the desired DHCP server.

2. When the DHCP Manager console opens, expand the DHCP server to reveal the IPv4 and IPv6 nodes.

3. Select and expand the IPv6 node, right-click the node, and select New Scope.

4. Click Next on the Welcome page.

5. On the Scope Name page, enter a name and description for the scope and click Next.

6. On the Scope Prefix page, enter the scope prefix and leave the default of 0 for the preference. For our example, we use 2001:dba:ce::/64 as the prefix and 0 …

There was much to examine about DHCP IPv6 in my previous post, so much that I omitted some elements.

For example: what is the DHCP IPv6 equivalent of the scope and server options? In particular the following:

— 003 — Router
— 006 — DNS Servers
— 015 — DNS Domain Name

 Indeed, if we look at DHCPv6 Server options, there is nothing, at first glance, that looks similar (please view the illustrations later in this blog post).

This is what I discovered.

003 — Router equivalent

First, in an IPv6 network, nodes are able to discover the default gateway (the router) automatically.

This reminded me of something I learned for the CCNA.

On one hand, IPv6 compatible routers advertise their presence to other nodes.

On the other, IPv6 nodes can solicit a router.

So, one way or another, the default gateway can be found, without any assistance from a DHCP server.

Therefore (it seems), there is no equivalent setting for «003 — Router» in DHCPv6.

In my practice network, I do not have a router that advertises itself or that other nodes can solicit.

Besides, I have disabled IPv4, resulting in a blank «Default Gateway» value (in the ipconfig output that can be viewed below — scroll).

006 DNS Servers and 015 DNS Domain Name equivalents

Accessing TCP/IP properties via ncpa.cpl (typed in «Run»), we can simply select: «Obtain an IPv6 address automatically» — and likewise for DNS.
 

Question: can an IPv6 client autoconfigure DNS settings?

It looks like it can try, producing (deprecated) fec0 entries:

C:\>ipconfig /all

Windows IP Configuration

   Host Name . . . . . . . . . . . . : PC1
   Primary Dns Suffix  . . . . . . . : machlinkit.biz
   [snip]
   DNS Suffix Search List. . . .. : machlinkit.biz

Ethernet adapter Local Area Connection:

   Connection-specific DNS Suffix  . : machlinkit.biz
   Description . . . . . . . . . . ….. : Intel(R) PRO/1000 MT Network Connection
   Physical Address. . . . . . . . . : 00-0C-29-F8-C0-46
   DHCP Enabled. . . . . . . . . . . : Yes
   Autoconfiguration Enabled .  : Yes
   IPv6 Address. . . . . . . . . …… . : fd00::116b:fdfc:25ea:4350(Preferred)
   Lease Obtained. . . . . . . . . : Thursday, November 07, 2015 9:24:26 PM
   Lease Expires . . . . . . . . . . : Tuesday, November 19, 2015 9:24:26 PM
   Link-local IPv6 Address . . . . . : fe80::e07e:50de:a86e:edc7%11(Preferred)
   Default Gateway . . . . . . . . . :
   DHCPv6 IAID . . . . . . . . . . . : 234884137
   DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-17-5D-69-C3-00-0C-29-F8-C0-46

   DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1
                                                 fec0:0:0:ffff::2%1
                                                 fec0:0:0:ffff::3%1

Note: for clarity and concision, to get «straight to the point», I have removed some of the ipconfig output.

The use of «fec0» is probably not recommended — and only present for lack of static configuration or DHCP automatic configuration.

IPv6 options 00023 and 00024

Moreover, «00024 — Domain Search List» is similar to «015 — DNS Domain Name»

   Host Name . . . . . . . . . . . . : PC1
   Primary Dns Suffix  . . . . . . . : machlinkit.biz
   [snip]
   DNS Suffix Search List. . . . . . : machlinkit.biz

Ethernet adapter Local Area Connection:

   Connection-specific DNS Suffix  . : machlinkit.biz
   Description . . . . . . . . . . . : Intel(R) PRO/1000 MT Network Connection
   Physical Address. . . . . . . . . : 00-0C-29-F8-C0-46
   DHCP Enabled. . . . . . . . . . . : Yes
   Autoconfiguration Enabled . . . . : Yes
   IPv6 Address. . . . . . . . . . . : fd00::33e5:ab3e:cd63:a38e(Preferred)
   Lease Obtained. . . . . . . . . . : Thursday, November 07, 2015 9:45:21 PM
   Lease Expires . . . . . . . . . . : Tuesday, November 19, 2015 9:45:21 PM
   Link-local IPv6 Address . . . . . : fe80::e07e:50de:a86e:edc7%11(Preferred)
   Default Gateway . . . . . . . . . :
   DHCPv6 IAID . . . . . . . . . . . : 234884137
   DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-17-5D-69-C3-00-0C-29-F8-C0-46

   DNS Servers . . . . . . . . . . . : fd00::10

So, the 00023 option does indeed configure the DNS server setting.

I’ll configure 00024 like this:

Here is the result:

Windows IP Configuration

   Host Name . . . . . . . . . . . . : PC1
   Primary Dns Suffix  . . . . . . . : machlinkit.biz
   [snip]   DNS Suffix Search List. . . . . . : machlinkit.biz
                                                     machlinkit.net

Ethernet adapter Local Area Connection:

   Connection-specific DNS Suffix  . : machlinkit.biz
   Description . . . . . . . . . . . : Intel(R) PRO/1000 MT Network Connection
   Physical Address. . . . . . . . . : 00-0C-29-F8-C0-46
   DHCP Enabled. . . . . . . . . . . : Yes
   Autoconfiguration Enabled . . . . : Yes
   IPv6 Address. . . . . . . . . . . : fd00::c896:5dbb:b8f9:636a(Preferred)
   Lease Obtained. . . . . . . . . . : Thursday, November 07, 2015 9:54:33 PM
   Lease Expires . . . . . . . . . . : Tuesday, November 19, 2015 9:54:33 PM
   Link-local IPv6 Address . . . . . : fe80::e07e:50de:a86e:edc7%11(Preferred)
   [snip]

   DNS Servers . . . . . . . . . . . : fd00::10
   NetBIOS over Tcpip. . . . . . : Disabled

   Connection-specific DNS Suffix Search List :
                                       machlinkit.biz
                                       machlinkit.net

So, the 00024 option does indeed configure the domain names that the client will use for name resolution.

*

This concludes my experiments with DHCP and IPv6 — for now…

New articles :

Здравствуйте многоуважаемые многоуважаемые форумчане!

Обращаюсь к вам за помощью, так как уже третьи сутки блуждая по просторам интернета и на данном форуме, я не смог ничего толкового найти
Итак недалече я сам себе задал задачу по системному администрированию. Поднять Active Directory и интернет-шлюз на Windows 2012 R2 (eng). Все сделал как описано в многочисленных статьях и видеоуроках. Кроме одного которого никак не могу найти как настроить основной шлюз в консоли DHCP V6.
Описываю все по порядку.
Установив на виртуальную машину VM WareWorkstation 15 pro я установил операционную систему Windows 2012 и поднял дополнительные роли

.
Также в свойствах сетевых адаптеров, я прописал статические IP-Address

Microsoft Windows [Version 6.3.9600]
(c) 2013 Microsoft Corporation. All rights reserved.

C:\Users\Administrator>ipconfig/all

Windows IP Configuration

Host Name . . . . . . . . . . . . : Server
Primary Dns Suffix . . . . . . . : kimson.net
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : Yes
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : kimson.net

Ethernet adapter inet:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Intel(R) 82574L Gigabit Network Connectio
n #2
Physical Address. . . . . . . . . : 00-0C-29-7D-DB-39
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::4900:c411:ec7d:60ac%14(Preferred)
IPv4 Address. . . . . . . . . . . : 192.168.19.4(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.19.2
DHCPv6 IAID . . . . . . . . . . . : 385879081
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-24-16-1B-5A-00-0C-29-7D-DB-2F

DNS Servers . . . . . . . . . . . : 192.168.19.2
NetBIOS over Tcpip. . . . . . . . : Enabled

Ethernet adapter local:

Connection-specific DNS Suffix . : kimson.net
Description . . . . . . . . . . . : Intel(R) 82574L Gigabit Network Connectio
n
Physical Address. . . . . . . . . : 00-0C-29-7D-DB-2F
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
IPv6 Address. . . . . . . . . . . : fd00::1(Preferred)
IPv6 Address. . . . . . . . . . . : fd00::d59c:ea0d:5f18:ca8c(Preferred)
Lease Obtained. . . . . . . . . . : Sunday, March 10, 2019 9:49:27 AM
Lease Expires . . . . . . . . . . : Friday, March 22, 2019 9:49:27 AM
Link-local IPv6 Address . . . . . : fe80::cca5:26d:648f:7ef0%12(Preferred)
Default Gateway . . . . . . . . . : ::
DHCPv6 IAID . . . . . . . . . . . : 301993001
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-24-16-1B-5A-00-0C-29-7D-DB-2F

DNS Servers . . . . . . . . . . . : ::1
NetBIOS over Tcpip. . . . . . . . : Disabled

Tunnel adapter isatap.{8259CFBA-06DF-430E-95B8-19AD3D854A5D}:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft ISATAP Adapter #2
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes

C:\Users\Administrator>

Далее я установил и настроил домен, dhcp и маршрутизацию(подробности указаны в скринах).

Active Directory — kimson.net

DHCP-Console

в консоли DHCP IPV6 прописал DNS.

Только никак не могу понять где там нужно прописать маршрутизатор чтобы сервер автоматически назначал Основной шлюз рабочим станциям.
Если Вам не трудно уважаемые форумчане, опишите по подробнее процесс (Так сказать для чайника) така как я только начинаю изучать системное администрирование.
Заранее благодарен