Domain Name System (DNS) is a distributed database used by TCP/IP applications to translate domain names into IP addresses. With DNS, you can use easy-to-remember domain names in some applications and let the DNS server translate them into correct IP addresses.

DNS services can be static or dynamic. After a user specifies a name, the device checks the local static name resolution table for an IP address. If no IP address is available, it contacts the DNS server for dynamic name resolution, which takes more time than static name resolution. To improve efficiency, you can put frequently queried name-to-IP address mappings in the local static name resolution table.

An AP can obtain a maximum of four AC addresses through DNS.

Static domain name resolution

Static domain name resolution means setting up mappings between domain names and IP addresses. IP addresses of the corresponding domain names can be found in the static domain resolution table when you use applications such as Telnet.

Dynamic domain name resolution

Resolution process

1. A user program sends a name query to the resolver of the DNS client.

2. The DNS resolver looks up the local domain name cache for a match. If the resolver finds a match, it sends the corresponding IP address back. If not, it sends a query to the DNS server.

3. The DNS server looks up the corresponding IP address of the domain name in its DNS database. If no match is found, the server sends a query to a higher level DNS server. This process continues until a result, whether successful or not, is returned.

4. After receiving a response from the DNS server, the DNS client returns the resolution result to the application.

Figure 1 Dynamic domain name resolution

Figure 1 shows the relationship between the user program, DNS client, and DNS server.

The DNS client includes the resolver and cache. The user program and DNS client can run on the same device or different devices, but the DNS server and the DNS client usually run on different devices.

Dynamic domain name resolution allows the DNS client to store latest DNS entries in the dynamic domain name cache. The DNS client does not need to send a request to the DNS server for a repeated query within the aging time. A DNS entry is removed when its aging timer expires. This makes sure the entries from the DNS server are up to date. The DNS server decides how long a mapping is valid, and the DNS client gets the aging information from DNS responses.

DNS suffixes

The DNS client holds a list of user-specified suffixes. The resolver can use the list to supply the missing part of incomplete names.

For example, a user can configure com as the suffix for aabbcc.com. The user only needs to enter aabbcc to obtain the IP address of aabbcc.com because the resolver adds the suffix and delimiter before passing the name to the DNS server.

· If there is no dot (.) in the domain name (for example, aabbcc), the resolver considers this a host name and adds a DNS suffix before the query. If no match is found after all the configured suffixes are used, the original domain name (for example, aabbcc) is used for the query.

· If there is a dot (.) in the domain name (for example, www.aabbcc), the resolver directly uses this domain name for the query. If the query fails, the resolver adds a DNS suffix for another query.

· If the dot (.) is at the end of the domain name (for example, aabbcc.com.), the resolver considers it a Fully Qualified Domain Name (FQDN) and returns the query result (successful or failed). The dot at the end of the domain name is considered a terminating symbol.

The device supports static and dynamic DNS client services.

NOTE:

If an alias is configured for a domain name on the DNS server, the device can resolve the alias into the IP address of the host.

DNS proxy

A DNS proxy forwards DNS requests and replies between DNS clients and a DNS server.

As shown in Figure 2, a DNS client sends a DNS request to the DNS proxy, which forwards the request to the designated DNS server, and then conveys the reply from the DNS server to the client.

The DNS proxy simplifies network management. When the DNS server address is changed, you can change the configuration on only the DNS proxy instead of on each DNS client.

Figure 2 DNS proxy networking application

A DNS proxy operates as follows:

1. A DNS client considers the DNS proxy to be the DNS server, and sends a DNS request to the DNS proxy. The destination address of the request is the IP address of the DNS proxy.

2. The DNS proxy searches the local static domain name resolution table and dynamic domain name resolution table after receiving the request. If the requested information is found, the DNS proxy returns a DNS reply to the client.

3. If the requested information is not found, the DNS proxy sends the request to the designated DNS server for domain name resolution.

4. After receiving a reply from the DNS server, the DNS proxy records the IP address-to-domain name mapping and forwards the reply to the DNS client.

With no DNS server or route to a DNS server specified, the DNS proxy does not forward DNS requests or answer requests from the DNS clients.

Configuring the IPv4 DNS client

Configuring static domain name resolution

Configuring static domain name resolution refers to specifying the mappings between host names and IPv4 addresses. Static domain name resolution allows applications such as Telnet to contact hosts by using host names instead of IPv4 addresses.

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 IPv4 address.	ip host hostname ip-address	Not configured by default. The IPv4 address you last assign to the host name overwrites the previous one if there is one. You can create up to 50 static mappings between domain names and IPv4 addresses.

Step

Command

Remarks

1. Enter system view.

system-view

N/A

2. Configure a mapping between a host name and an IPv4 address.

ip host hostname ip-address

Not configured by default.

The IPv4 address you last assign to the host name overwrites the previous one if there is one.

You can create up to 50 static mappings between domain names and IPv4 addresses.

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.

Configuration guidelines

Follow these guidelines when you configure dynamic domain name resolution:

· You can configure up to six DNS servers in system view, including those with IPv6 addresses, and up to six DNS servers on all interfaces of a device.

· A DNS server configured in system view has a higher priority than one configured in interface view. A DNS server configured earlier has a higher priority than one configured later in the same view. A DNS server manually configured has a higher priority than one dynamically obtained through DHCP. A name query request is first sent to the DNS server that has the highest priority. If no reply is received, it is sent to the DNS server that has the second highest priority, and so on in turn.

· You can specify up to 10 DNS suffixes.

Configuration procedure

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.	· Method 1 (In system view): dns server ip-address · Method 2 (In interface view): a. interface interface-type interface-number b. dns server ip-address c. quit	Use at least one Method. No DNS server is specified by default.
4. Configure a DNS suffix.	dns domain domain-name	Optional. By default, no DNS suffix is configured, and only the provided domain name is resolved.

Configuring the DNS proxy

You can specify multiple DNS servers. Upon receiving a name query request from a client, the DNS proxy forwards the request to the DNS server that has the highest priority. If the DNS proxy does not receive a reply, it forwards the request to a DNS server that has the second highest priority, and so on in turn.

To configure the DNS proxy:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enable DNS proxy.	dns proxy enable	Disabled by default.
3. Specify a DNS server.	· Method 1 (In system view): dns server ip-address · Method 2 (In interface view): a. interface interface-type interface-number b. dns server ip-address	Use at least one Method. No DNS server is specified by default.

Specifying the source interface for DNS packets

By default, the device uses the primary IP address of the output interface of the matching route as the source IP address of a DNS request. Therefore, the source IP address of the DNS packets might vary with DNS servers. In some scenarios, the DNS server only responds to DNS requests sourced from a specific IP address. In such cases, you must specify the source interface for the DNS packets so that the device can always use the primary IP address of the specified source interface as the source IP address of DNS packets.

To specify the source interface for DNS packets:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Specify the source interface for DNS packets.	dns source-interface interface-type interface-number	By default, no source interface for DNS packets is specified. The device uses the primary IP address of the output interface of the matching route as the source IP address of a DNS request.

Displaying and maintaining IPv4 DNS

Task	Command	Remarks
Display the static IPv4 domain name resolution table.	display ip host [ \| { begin \| exclude \| include } regular-expression ]	Available in any view.
Display IPv4 DNS server information.	display dns 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 information about the dynamic IPv4 domain name cache.	display dns host ip [ \| { begin \| exclude \| include } regular-expression ]	Available in any view.
Clear information about the dynamic IPv4 domain name cache.	reset dns host ip	Available in user view.

IPv4 DNS configuration examples

Static domain name resolution configuration example

Network requirements

As shown in Figure 3, the AC wants to access the host by using an easy-to-remember domain name rather than an IP address.

Configure static domain name resolution on the AC so that the AC can use the domain name host.com to access the host whose IP address is 10.1.1.2.

Figure 3 Network diagram

Configuration procedure

# Configure a mapping between host name host.com and IP address 10.1.1.2.

<AC> system-view

[AC] ip host host.com 10.1.1.2

# Execute the ping host.com command to verify that AC can use the static domain name resolution to get the IP address 10.1.1.2 corresponding to host.com.

[AC] ping host.com

PING host.com (10.1.1.2):

56 data bytes, press CTRL_C to break

Reply from 10.1.1.2: bytes=56 Sequence=1 ttl=128 time=1 ms

Reply from 10.1.1.2: bytes=56 Sequence=2 ttl=128 time=4 ms

Reply from 10.1.1.2: bytes=56 Sequence=3 ttl=128 time=3 ms

Reply from 10.1.1.2: bytes=56 Sequence=4 ttl=128 time=2 ms

Reply from 10.1.1.2: bytes=56 Sequence=5 ttl=128 time=3 ms

--- host.com ping statistics ---

5 packet(s) transmitted

5 packet(s) received

0.00% packet loss

round-trip min/avg/max = 1/2/4 ms

Dynamic domain name resolution configuration example

Network requirements

As shown in Figure 4, the AC wants to access the host by using an easy-to-remember domain name rather than an IP address, and to request the DNS server on the network for an IP address by using dynamic domain name resolution. The IP address of the DNS server is 2.1.1.2/16 and the DNS server has a com domain, which stores the mapping between domain name host and IP address 3.1.1.1/16.

AC serves as a DNS client, and uses dynamic domain name resolution and the suffix to access the host with the domain name host.com and the IP address 3.1.1.1/16.

Figure 4 Network diagram

Configuration procedure

Before performing the following configuration, make sure the AC and the host are reachable to each another, and the IP addresses of the interfaces are configured as shown Figure 4.

This configuration might vary with DNS servers. The following configuration is performed on a PC running Windows Server 2000.

1. Configure the DNS server:

a. Select Start > Programs > Administrative Tools > DNS.

The DNS server configuration page appears, as shown in Figure 5.

b. Right-click Forward Lookup Zones, select New Zone, and then follow the instructions to create a new zone named com.

Figure 5 Creating a zone

c. On the DNS server configuration page, right-click zone com, and select New Host.

Figure 6 Adding a host

d. On the page that appears, enter host name host and IP address 3.1.1.1.

e. Click Add Host.

The mapping between the IP address and host name is created.

Figure 7 Adding a mapping between domain name and IP address

2. Configure the DNS client:

# Enable dynamic domain name resolution.

<AC> system-view

[AC] dns resolve

# Specify the DNS server 2.1.1.2.

[AC] dns server 2.1.1.2

# Configure com as the name suffix.

[AC] dns domain com

Verifying the configuration

# Execute the ping host command on AC to verify that the communication between AC and the host is normal and that the corresponding destination IP address is 3.1.1.1.

[AC] ping host

Trying DNS resolve, press CTRL_C to break

Trying DNS server (2.1.1.2)

PING host.com (3.1.1.1):

56 data bytes, press CTRL_C to break

Reply from 3.1.1.1: bytes=56 Sequence=1 ttl=126 time=3 ms

Reply from 3.1.1.1: bytes=56 Sequence=2 ttl=126 time=1 ms

Reply from 3.1.1.1: bytes=56 Sequence=3 ttl=126 time=1 ms

Reply from 3.1.1.1: bytes=56 Sequence=4 ttl=126 time=1 ms

Reply from 3.1.1.1: bytes=56 Sequence=5 ttl=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 = 1/1/3 ms

DNS proxy configuration example

Network requirements

When the IP address of the DNS server changes, you must configure the new IP address of the DNS server on each device on the LAN. To simplify network management, you can use the DNS proxy function.

As shown in Figure 8:

· AC 1 acts as a DNS proxy. The IP address of the real DNS server is 4.1.1.1.

· Specify the IP address of the DNS server as AC 2's IP address. DNS requests of AC 2 are forwarded to the real DNS server through the DNS proxy.

Figure 8 Network diagram

Configuration procedure

Before performing the following configuration, assume that AC 1, the DNS server, and the host are reachable to each other and that the IP addresses of the interfaces are configured as shown in Figure 8.

1. Configure the DNS server:

This configuration might vary with DNS servers. When a Windows server 2000 PC acts as the DNS server, see "Dynamic domain name resolution configuration example" for related configuration information.

2. Configure the DNS proxy AC1:

# Specify the DNS server 4.1.1.1.

<AC1> system-view

[AC1] dns server 4.1.1.1

# Enable DNS proxy.

[AC1] dns proxy enable

3. Configure the DNS client AC 2:

# Enable the domain name resolution function.

<AC2> system-view

[AC2] dns resolve

# Specify the DNS server 2.1.1.2.

[AC2] dns server 2.1.1.2

Verifying the configuration

# Execute the ping host.com command on AC 2 to verify that the communication between the client and the host is normal and that the corresponding destination IP address is 3.1.1.1.

[AC2] ping host.com

Trying DNS resolve, press CTRL_C to break

Trying DNS server (2.1.1.1)

PING host.com (3.1.1.1):

56 data bytes, press CTRL_C to break

Reply from 3.1.1.1: bytes=56 Sequence=1 ttl=126 time=3 ms

Reply from 3.1.1.1: bytes=56 Sequence=2 ttl=126 time=1 ms

Reply from 3.1.1.1: bytes=56 Sequence=3 ttl=126 time=1 ms

Reply from 3.1.1.1: bytes=56 Sequence=4 ttl=126 time=1 ms

Reply from 3.1.1.1: bytes=56 Sequence=5 ttl=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 = 1/1/3 ms

Troubleshooting IPv4 DNS configuration

Symptom

After enabling dynamic domain name resolution, the user cannot get the correct IP address.

Solution

1. Use the display dns host ip command to verify that the specified domain name is in the cache.

2. If the specified domain name does not exist, check that dynamic domain name resolution is enabled and that the DNS client can communicate with the DNS server.

3. If the specified domain name is in the cache but the IP address is incorrect, check that the DNS client has the correct IP address of the DNS server.

4. Verify that the mapping between the domain name and IP address is correct on the DNS server.

Configuring DDNS

Support for this feature depends on the device model. For more information, see About the H3C Access Controllers Configuration Guides.

Overview

DNS provides only the static mappings between domain names and IP addresses. When the IP address of a node changes, your access to the node fails.

Dynamic Domain Name System (DDNS) can dynamically update the mappings between domain names and IP addresses for DNS servers.

DDNS is supported by only IPv4 DNS, and it is used to update the mappings between domain names and IPv4 addresses.

DDNS application

As shown in Figure 9, DDNS works on the client-server model.

· DDNS client—A device that needs to dynamically update the mapping between the domain name and the IP address on the DNS server when the client's IP address changes. An Internet user typically uses the domain name to access an application layer server such as an HTTP server or an FTP server. When its IP address changes, the application layer server runs as a DDNS client that sends a request to the DDNS server to update the mapping between the domain name and the IP address.

· DDNS server—Informs the DNS server of latest mappings. When receiving the mapping update request from a DDNS client, the DDNS server tells the DNS server to re-map between the domain name and the IP address of the DDNS client. Therefore, the Internet users can use the same domain name to access the DDNS client even if the IP address of the DDNS client has changed.

Figure 9 DDNS networking application

With the DDNS client configured, a device can dynamically update the latest mapping between its domain name and IP address on the DNS server through DDNS servers.

The DDNS update process does not have a unified standard but depends on the DDNS server that the DDNS client contacts. The well-known DDNS service providers include www.3322.org, www.oray.cn (also known as the PeanutHull server), and www.dyndns.com.

DDNS client configuration task list

Task	Remarks
Configuring a DDNS policy	Required.
Applying the DDNS policy to an interface	Required.

Configuring a DDNS policy

A DDNS policy includes the DDNS server address, port number, login ID, password, time interval, associated SSL client policy, and update time interval. After creating a DDNS policy, you can apply it to multiple interfaces to simplify DDNS configuration.

The URL addresses configured for update requests vary by DDNS server.

· When a DDNS client contacts a DDNS server at www.3322.org by using HTTP, the URL address for update requests should be configured as:

http://username:password@members.3322.org/dyndns/update?system=dyndns&hostname=<h>&myip=<a>

· When a DDNS client contacts a PeanutHull DDNS server by using TCP, the URL address for update requests should be configured as:

oray://username:password@phservice2.oray.net

Replace the parameters username and password in the URL with your actual login ID and password registered at the DDNS service provider's website.

members.3322.org and phservice2.oray.net are the domain names of DDNS servers. The domain names of PeanutHull DDNS servers can be phservice2.oray.net, phddns60.oray.net, client.oray.net, ph031.oray.net, and so on. Determine the domain name in the URL according to the actual situation.

The system automatically fills <h> with the FQDN that is specified when the DDNS policy is applied to the interface and automatically fills <a> with the primary IP address of the interface to which the DDNS policy is applied. You may also manually specify an FQDN and an IP address in <h> and <a>, respectively. After that, the FQDN that is specified when the DDNS policy is applied becomes ineffective. H3C recommends you do not change <h> and <a> in the URL address because your configuration may be incorrect. For more information about applying DDNS policies, see "Applying the DDNS policy to an interface."

NOTE:

The FQDN is the only identification of a node in the network. An FQDN consists of a local host name and a parent domain name and can be translated into an IP address.

Configuration prerequisites

Visit the website of a DDNS service provider, register an account, and apply for a domain name for the DDNS client. When the DDNS client updates the mapping between the domain name and the IP address through the DDNS server, the DDNS server checks whether the account information is correct and whether the domain name to be updated belongs to the account.

Configuration procedure

To configure a DDNS policy:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Create a DDNS policy and enter its view.	ddns policy policy-name	By default, no DDNS policy is created.
3. Specify a URL address for DDNS update requests.	url request-url	By default, no URL address is specified for DDNS update requests.
4. Associate an SSL client policy with the DDNS policy.	ssl client policy policy-name	Optional. By default, no SSL client policy is associated with the DDNS policy. This step is only effective and a must for HTTP-based DDNS update requests. For SSL client policy configuration, see Security Configuration Guide.
5. Specify the interval for sending update requests.	interval days [ hours [ minutes ] ]	Optional. By default, the time interval is one hour.

The URL address for an update request can start with http://, https://, or oray://.

· http:// indicates the HTTP-based DDNS server.

· https:// indicates the HTTPS-based DDNS server.

· oray:// indicates the TCP-based PeanutHull server.

Applying the DDNS policy to an interface

After you apply the DDNS policy to an interface and specify the FQDN for update, the DDNS client sends requests to the DDNS server to update the mapping between the domain name and the primary IP address of the interface at the specified interval.

Before you apply a DDNS policy to an interface, complete the following tasks:

· Specify the primary IP address of the interface and make sure that the DDNS server and the interface can reach each other.

· Configure static or dynamic domain name resolution to translate the domain name of the DDNS server into the IPv4 address. For more information, see "Configuring the IPv4 DNS client."

To apply the DDNS policy to an interface:

Step	Command	Remarks
1. Enter system view.	system-view	N/A
2. Enter interface view.	interface interface-type interface-number	N/A
3. Apply the DDNS policy to the interface to update the mapping between the specified FQDN and the primary IP address of the interface, and enable DDNS update.	ddns apply policy policy-name [ fqdn domain-name ]	By default, no DDNS policy is applied to the interface, no FQDN is specified for update, and DDNS update is disabled.

If the DDNS service is provided by www.3322.org, the FQDN of the mapping to be updated must be specified. Otherwise, DDNS update may fail.

If the DDNS server is a PeanutHull server and no FQDN is specified, the DDNS server updates all the corresponding domain names of the DDNS client account. If an FQDN is specified, the DDNS server updates only the mapping between the specified FQDN and the primary IP address.

Displaying and maintaining DDNS

Task	Command	Remarks
Display information of the DDNS policy.	display ddns policy [ policy-name ] [ \| { begin \| exclude \| include } regular-expression ]	Available in any view

DDNS configuration examples

DDNS configuration example with www.3322.org

Network requirements

As shown in Figure 10, AC is a Web server with the domain name whatever.3322.org.

AC acquires the IP address through DHCP. Through DDNS service provided by www.3322.org, AC informs the DNS server of the latest mapping between its domain name and IP address.

The IP address of the DNS server is 1.1.1.1. AC uses the DNS server to translate www.3322.org into the corresponding IP address.

Figure 10 Network diagram

Configuration procedure

Before configuring DDNS on AC, register with username steven and password nevets at http://www.3322.org/, add AC's host name-to-IP address mapping to the DNS server, and make sure that the devices are reachable to each other.

# Create a DDNS policy named 3322.org, and enter its view.

<AC> system-view

[AC] ddns policy 3322.org

# Specify for DDNS update requests the URL address with the login ID steven and password nevets.

[AC-ddns-policy-3322.org] url http://steven:[email protected]/dyndns/update?system=dyndns&hostname=<h>&myip=<a>

# Set the interval for sending DDNS update requests to 15 minutes.

[AC-ddns-policy-3322.org] interval 0 0 15

[AC-ddns-policy-3322.org] quit

# Enable dynamic domain name resolution on AC.

[AC] dns resolve

# Specify the IP address of the DNS server as 1.1.1.1.

[AC] dns server 1.1.1.1

# Apply DDNS policy 3322.org to interface Dialer1 to enable DDNS update and dynamically update the mapping between domain name whatever.3322.org and the primary IP address of Dialer1.

[AC] interface ethernet 1/1

[AC-Dialer1] ddns apply policy 3322.org fqdn whatever.3322.org

After the preceding configuration is completed, AC notifies the DNS server of its new domain name-to-IP address mapping through the DDNS server provided by www.3322.org, whenever the IP address of AC changes. Therefore, AC can always provide Web service at whatever.3322.org.

DDNS configuration example with Peanuthull server

Network requirements

As shown in Figure 11, AC is a Web server with domain name whatever.gicp.cn.

AC acquires the IP address through DHCP. Through the PeanutHull server, AC informs the DNS server of the latest mapping between its domain name and IP address.

The IP address of the DNS server is 1.1.1.1. AC uses the DNS server to translate www.oray.cn into the corresponding IP address.

Figure 11 Network diagram

Configuration procedure

Before configuring DDNS on AC, register with username steven and password nevets at http://www.oray.cn/, add AC's host name-to-IP address mapping to the DNS server, and make sure that the devices are reachable to each other.

# Create a DDNS policy named oray.cn and enter its view.

<AC> system-view

[AC] ddns policy oray.cn

# Specify for DDNS update requests the URL address with the login ID steven and password nevets.

[AC-ddns-policy-oray.cn] url oray://steven:[email protected]

# Set the DDNS update request interval to 12 minutes.

[AC-ddns-policy-oray.cn] interval 0 0 12

[AC-ddns-policy-oray.cn] quit

# Enable dynamic domain name resolution on AC.

[AC] dns resolve

# Specify the IP address of the DNS server as 1.1.1.1.

[AC] dns server 1.1.1.1

# Apply the DDNS policy to interface Dialer1 to enable DDNS update and dynamically update the mapping between whatever.gicp.cn and the primary IP address of Dialer1.

[AC] interface ethernet 1/1

[AC-Dialer1] ddns apply policy oray.cn fqdn whatever.gicp.cn

After the preceding configuration is completed, AC notifies the DNS server of its new domain name-to-IP address mapping through the PeanutHull server, whenever the IP address of AC changes. Therefore, AC can always provide Web service at whatever.gicp.cn.

04-Layer 3 Configuration Guide

Overview

Dynamic domain name resolution

Resolution process

DNS suffixes

DNS proxy

Configuring dynamic domain name resolution

Configuration guidelines

Configuration procedure

Configuring the DNS proxy

Specifying the source interface for DNS packets

IPv4 DNS configuration examples

Network requirements

Configuration procedure

Network requirements

Configuration procedure

Verifying the configuration

Network requirements

Configuration procedure

Verifying the configuration

Troubleshooting IPv4 DNS configuration

Symptom

Solution

Configuring a DDNS policy

DDNS configuration example with www.3322.org

Network requirements

Configuration procedure

DDNS configuration example with Peanuthull server

Network requirements

Configuration procedure

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