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How to configure a dual-stack.

In special cases a LAN needs two pool of addresses with different versions, Ipv4 and Ipv6. In this little document I´m going to explain how to create this two pool using a device and a giving dynamic addresses as well.

First enable dual-stack feature

STEP 1 Choose Networking > IPv6 > IP Mode.

STEP 2 Click the IPv4 and IPv6 Dual-Stack radio button.

STEP 3 Click Save.

NOTE: The router reboots after changing the IP mode.

After that, you have to configure IPv6 LAN properties:

STEP 1: Choose Networking > IPv6 > IPv6 LAN (Local Area Network).

STEP 2 : Under LAN TCP/IP Setup, in the IPv6 Address field, enter the IP address of the Cisco RV180/RV180W. The default IPv6 address for the gateway is fec0::1. You can change this 128 bit IPv6 address based on your network requirements.

STEP 3: Enter the IPv6 prefix length. The IPv6 network (subnet) is identified by the initial bits of the address called the prefix. By default, the prefix is 64 bits long. All hosts  in the network have the identical initial bits for their IPv6 address; the number of common initial bits in the network's addresses is set by the prefix length field.

STEP  4: In the DHCPv6 field, choose to disable or enable the DHCPv6 server. If enabled, the Cisco RV180/RV180W assigns an IP address within the specified range plus additional specified information to any LAN endpoint that requests DHCP-served addresses.

STEP 5: Choose the DHCP mode. If stateless is selected, an external IPv6 DHCP server is not required as the IPv6 LAN hosts are auto-configured by the Cisco RV180/RV180W. In this case, the router advertisement daemon (RADVD) must be configured on this device and ICMPv6 router discovery messages are used by the host for auto-configuration. There are no managed addresses to serve the LAN nodes. If stateful is selected, the IPv6 LAN host will rely on an external DHCPv6 server to provide required configuration settings.

STEP 6: (Optional) Enter the domain name of the DHCPv6 server.

STEP 7: Enter the server preference. This field is used to indicate the preference level of this DHCP server. DHCP advertise messages with the highest server preference value to a LAN host are preferred over other DHCP server advertise messages. The default is 255.

STEP 8: Choose the DNS proxy behavior:

Use DNS Proxy—Check this box to enable DNS proxy on this LAN, or uncheck this box to disable this proxy. When this feature is enabled, the router acts as a proxy for all DNS requests and communicate with the ISP’s DNS servers (as configured in the WAN settings page).

Use DNS from ISP—This option allows the ISP to define the DNS servers (primary/secondary) for the LAN DHCP client.

Use below—If selected, the primary/secondary DNS servers configured are used. If you chose this option, enter the IP address of the primary and secondary DNS servers.

STEP 9: Enter the lease/rebind time. Enter the duration (in seconds) for which IP addresses will be leased to endpoints on the LAN.

STEP 10: Click Save.

Now you have to configure IPv4 LAN and DHCP properties:

Lan Settings:

STEP 1: Choose Networking > LAN (Local Network) > IPv4 LAN (Local Network).

STEP 2: Enter this information:

IP Address Enter the LAN IP address of the RV180/RV180W. Make sure the address is not in use by another device on the same network.

Subnet mask Choose the subnet mask for the new IP address from the drop-down menu. The default subnet is

STEP 3: Click Save.

DHCP Settings:

STEP 1: Choose Networking > LAN (Local Network) > IPv4 LAN (Local Network).

STEP 2: From the DHCP Mode drop-down menu, choose one of these options:

None—Choose this option if the Cisco RV180/RV180W is not going to act as  a DHCP server.

DHCP Server—Choose this option to configure the Cisco RV180/RV180W  to be a DHCP server and enter this information:

-Domain Name— (Optional) Enter the domain name for your network.Configuring Networking

-Starting IP Address/Ending IP Address—Enter the first and last of the  contiguous addresses in the IP address pool. Any new DHCP client joining the LAN is assigned an IP address in this range. You can save part  of the range for PCs with fixed addresses. These addresses should be in  the same IP address subnet as the Cisco RV180/RV180W's LAN IP address.

- Primary DNS Server/Secondary DNS Server—DNS servers map Internet domain names (for example, to IP addresses. Enter the server IP addresses in these fields if you want to use differentDNS servers than are specified in your WAN settings.

- Lease time—Enter the duration (in hours) for which IP addresses are leased to clients.

DHCP Relay—Choose this option to configure the Cisco RV180/RV180W to be a DHCP relay agent and enter the address of the remote DHCP server in the Remote DHCP Server field. The relay agent transmits DHCP messages between multiple subnets.

STEP 3: Click Save.

After you complete these few steps, your port has to be a DHCP v4 and v6 server for both subnets

***Please  rate it so other users can benefit from it"***


Johnnatan Rodriguez Miranda.

Cisco Network Support Engineer.

"Guide Me",  a useful tool

Cisco has a very useful tool called GuideMe, is made for small business products, and your device is in this category, you can use this address for accessing the tool:, is very easy to use, just complete the 3 spaces on this way:

Select a category: (Select the device type on request), e.g. Routers

Enter model: (Type the model on request), e.g. RV042

Question: (Type what you want to know about the device), e.g. VPN

And it'll be showing all the information you need about what you wrote.

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Last update:
‎02-13-2013 07:38 AM
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