TCP/IPv6 Configuration and Management Manual (G06.24+)
Example Illustrations and Adding Features to the 
Basic Configuration
HP NonStop TCP/IPv6 Configuration and Management Manual—524523-008
5-6
DUAL-Mode, Configured Tunnel
page 8-57 in the ADD SUBNET Command for TCP6MAN on page 8-26 
description.
•
For Ethernet failover, nonshared IP, you do not need a reserved IP address.
DUAL-Mode, Configured Tunnel
Example 1-10 on page 1-20 shows how to configure the subsystem with a configured 
tunnel. This configuration is shown in Figure 5-5.
In NonStop TCP/IPv6, after you establish the TCP6MON in DUAL mode and you add 
an INET type SUBNET (IPv4), an automatic tunnel SUBNET named TUN is added to 
the system. If you want to create another tunnel, add a SUBNET of TYPE TUN (with a 
name starting with IPT) and specify both source and destination IP addresses. 
A configured tunnel allows full IPv6 addressing and functionality between your host 
and another IPv6 host over an IPv4 network. Automatic tunneling requires no 
configuration and also lets you communicate over an IPv4 network but automatic 
tunneling is limited to IPv4 addressing and functionality. 
This example shows that:
•
First you add and start a DUAL-mode SUBNET 
•
The next step is to add a SUBNET of TYPE TUNNEL and ALTER it to bring up 
IPv6. 
The IPTSRC and IPTDST attributes set the IPv4 source and destination addresses 
in the encapsulating header. These addresses are local and destination end points 
for data communications. The local endpoint SUBNET, in this case SN3 with 
address 172.14.215.27, must be configured before you add the configured tunnel.
(For more information about tunnels, see How IPv6 Tunnels Work
 on page A-18.)
Figure 5-5. DUAL-Mode SUBNET, Configured Tunnel, Example 1-10
Host, Dual Mode
172.14.215.27
SN3
VST136.vsd
IPT1
(tunnel)
IPv6 Host
IPv4/6 Network
Automatically-assigned
IPv6 address (SN3)
172.14.215.27
172.17.215.240
TUN










