Configuring IPv6 DNS· 1

Configuring the IPv6 DNS client 1

Configuring static domain name resolution· 1

Configuring dynamic domain name resolution· 1

Displaying and maintaining IPv6 DNS· 2

Static domain name resolution configuration example· 2

Network requirements 2

Configuration procedure· 3

Dynamic domain name resolution configuration example· 3

Network requirements 3

 

IPv6 Domain Name System (DNS) is responsible for translating domain names into IPv6 addresses. Like IPv4 DNS, IPv6 DNS includes static domain name resolution and dynamic domain name resolution. The functions and implementations of the two types of domain name resolution are the same as those of IPv4 DNS. For more information, see "Configuring IPv4 DNS."

Configuring the IPv6 DNS client

This section explains how to configure static and dynamic domain resolution for the IPv6 DNS client.

Configuring static domain name resolution

Configuring static domain name resolution refers to specifying the mappings between host names and IPv6 addresses. Static domain name resolution allows applications such as Telnet to contact hosts by using host names instead of IPv6 addresses.

Follow these guidelines when you configure static domain name resolution:

·          A host name can be mapped to one IPv6 address only. If you map a host name to different IPv6 addresses, the last configuration takes effect.

·          You can configure up to 50 mappings between domain name and IPv6 address on a device.

To configure static domain name resolution:

 

Step	Command	Remarks
1.       Enter system view.	system-view	N/A
2.       Configure a mapping between a host name and an IPv6 address.	ipv6 host hostname ipv6-address	Not configured by default.

 

Configuring dynamic domain name resolution

To send DNS queries to a correct server for resolution, you must enable dynamic domain name resolution and configure a DNS server.

In addition, you can configure a DNS suffix that the system automatically adds to the provided domain name for resolution.

Follow these guidelines when you configure dynamic domain name resolution:

·          You can configure up to six DNS servers, including those with IPv4 addresses on a device.

·          You can specify up to ten DNS suffixes on a device.

To configure dynamic domain name resolution:

 

Step	Command	Remarks
1.       Enter system view.	system-view	N/A
2.       Enable dynamic domain name resolution.	dns resolve	Disabled by default.
3.       Specify a DNS server.	dns server ipv6 ipv6-address [ interface-type interface-number ]	Not specified by default. If the IPv6 address of a DNS server is a link-local address, you need to specify the interface-type and interface-number arguments.
4.       Configure a DNS suffix.	dns domain domain-name	Optional. Not configured by default. Only the provided domain name is resolved.

 

Displaying and maintaining IPv6 DNS

 

Task	Command	Remarks
Display the static IPv6 domain name resolution table.	display ipv6 host [ | { begin | exclude | include } regular-expression ]	Available in any view.
Display IPv6 DNS server information.	display dns ipv6 server [ dynamic ] [ | { begin | exclude | include } regular-expression ]	Available in any view.
Display DNS suffixes.	display dns domain [ dynamic ] [ | { begin | exclude | include } regular-expression ]	Available in any view.
Display the information of dynamic IPv6 domain name cache.	display dns host ipv6 [ | { begin | exclude | include } regular-expression ]	Available in any view.
Clear the information of dynamic IPv6 domain name cache.	reset dns host ipv6	Available in user view.

 

Static domain name resolution configuration example 

Network requirements

As shown in Figure 1, the AP wants to access the client by using an easy-to-remember domain name rather than an IPv6 address. Configure static domain name resolution on the AP so that the AP can use the domain name host.com to access the client whose IPv6 address is 1::2.

Figure 1 Network diagram

 

Configuration procedure

# Configure a mapping between host name host.com and IPv6 address 1::2.

<AP> system-view

[AP] ipv6 host host.com 1::2

# Enable IPv6 packet forwarding.

[AP] ipv6

# Use the ping ipv6 host.com command to verify that the AP can use static domain name resolution to resolve domain name host.com into IPv6 address 1::2.

[AP] ping ipv6 host.com

  PING host.com (1::2):

  56  data bytes, press CTRL_C to break

    Reply from 1::2

    bytes=56 Sequence=1 hop limit=128  time = 3 ms

    Reply from 1::2

    bytes=56 Sequence=2 hop limit=128  time = 1 ms

    Reply from 1::2

    bytes=56 Sequence=3 hop limit=128  time = 1 ms

    Reply from 1::2

    bytes=56 Sequence=4 hop limit=128  time = 2 ms

    Reply from 1::2

    bytes=56 Sequence=5 hop limit=128  time = 2 ms

  --- host.com ping statistics ---

    5 packet(s) transmitted

    5 packet(s) received

    0.00% packet loss

    round-trip min/avg/max = 1/1/3 ms

Dynamic domain name resolution configuration example

Network requirements

As shown in Figure 2, the AP wants to access the client by using an easy-to-remember domain name rather than an IPv6 address. The IPv6 address of the DNS server is 2::2/64 and the server has a com domain, which stores the mapping between domain name host and IPv6 address 1::1/64.

Configure dynamic domain name resolution and the domain name suffix com on the AP that acts as a DNS client so that it can use domain name host to access the client with the domain name host.com and the IPv6 address 1::1/64.

Figure 2 Network diagram

 

Configuration procedure

Before performing the following configuration, make sure the AP and the client are accessible to each other via available routes, and the IPv6 addresses of the interfaces are configured as shown Figure 2.

This configuration may vary with DNS servers. The following configuration is performed on a PC running Windows Server 2003. Make sure that the DNS server supports the IPv6 DNS function so that the server can process IPv6 DNS packets, and the interfaces of the DNS server can forward IPv6 packets.

1.        Configure the DNS server:

# Enter the DNS server configuration page.

Select Start > Programs > Administrative Tools > DNS.

# Create zone com.

As shown in Figure 3, right click Forward Lookup Zones, select New Zone, and then follow the instructions to create a new zone named com.

Figure 3 Create a zone

 

# Create a mapping between the host name and the IPv6 address.

As shown in Figure 4, right click zone com.

Figure 4 Create a record

 

In Figure 4, select Other New Records to bring up a dialog box as shown in Figure 5. Select IPv6 Host (AAA) as the resource record type.

Figure 5 Select the resource record type

 

As shown in Figure 6, type host name host and IPv6 address 1::1, and then click OK.

Figure 6 Add a mapping between domain name and IPv6 address

 

2.        Configure the DNS client:

# Enable dynamic domain name resolution.

<AP> system-view

[AP] dns resolve

# Specify the DNS server 2::2.

[AP] dns server ipv6 2::2

# Configure com as the DNS suffix.

[AP] dns domain com

3.        Configuration verification:

# Use the ping ipv6 host command on the AP to verify that the communication between the AP and the client is normal and that the corresponding destination IP address is 1::1.

[AP] ping ipv6 host

 Trying DNS resolve, press CTRL_C to break

 Trying DNS server (2::2)

  PING host.com (1::1):

  56  data bytes, press CTRL_C to break

    Reply from 1::1

    bytes=56 Sequence=1 hop limit=126  time = 2 ms

    Reply from 1::1

    bytes=56 Sequence=2 hop limit=126  time = 1 ms

    Reply from 1::1

    bytes=56 Sequence=3 hop limit=126  time = 1 ms

    Reply from 1::1

    bytes=56 Sequence=4 hop limit=126  time = 1 ms

    Reply from 1::1

    bytes=56 Sequence=5 hop limit=126  time = 1 ms

 

  --- host.com ping statistics ---

    5 packet(s) transmitted

    5 packet(s) received

    0.00% packet loss

    round-trip min/avg/max = 1/1/2 ms