Ok, here's my best stab at walking you through the IPv6 tunnel settings I've put into my router ...
Following the Cisco document "Connecting RV220W to an IPv6 Tunnel broker", and after setting up my /64 tunnel on
the HE side, I followed this procedure. My firmware version is 220.127.116.11, so my screens didn't exactly match the
screenshots in the document. In cases where I didn't have an exact match to choose I made a best educated guess.
This, by the way, is also the order in which I made the settings. Here we go!
I first went to Networking > IPv6 > Routing Mode and selected radio button next to "IPv4 / IPv6 mode".
Next, went to Netowrking > IPv6 > Router Advertisement and set RADVD Status: to "Enable", Advertise Mode: to
"Unsolicited Multicast", Advertise Interval: to "30", RA Flags: have Managed and Other checked, Router Preference:
is set to "High", MTU: is set to "1500", and Router Life Time: is set to "3600".
At this point, my clients (PCs) were not acquiring 6to4 prefixes (2002:WAN IP in HEX:
as the documentation said
that I should have. I continued anyway.
Next, I went to Networking > IPv6 > Advertisement Prefixes, and clicked the Add button. In the following screen, I
set the IPv6 Prefix Type: to "6to4", the SLA ID: to "1", checked that the IPV6 Prefix (although greyed out): is
"2002:<My WAN IP in Hex>:1::", the IPv6 Prefix Length (also greyed out): is "64", and the Prefix Lifetime: is
"3600". I then clicked the Save button.
I then went to Networking > IPv6 > 6 to 4 Tunneling and checked "Enabled" for Automatic Tunneling.
Next, I went to Networking > IPv6 > IPv6 Static Routing and clicked Add. On the next screen, I set the Route Name:
to "tunnelbroker", Active: has "Enable" checked, IPv6 Destination is set to "2001:", IPv6 Prefix Length" is set to
"3", Interface: has "sit0 Wan" selected", IPv6Gateway: is set to "::18.104.22.168" (HE Server IPv4 address), and
the Metric: is set to "2".
Lastly, I went to Networking > IPv6 > Advertising Prefixes again and clicked Add. Following screen, IPv6 Prefix Type: is "Global/Local/ISATAP", SLA ID: is greyed out and blank, IPV6 Prefix: is "<My HE Routed /64 Prefix>::2", IPv6 Prefix Length: is "64", and Prefix Lifetime: is "3600".
At this point when nothing seemed to be working, I rebooted the router as I had read in other posts that sometimes a reboot would bring up the tunnel after the settings were in place. No difference, still no working.
One thing that I have tried after all of this is I went to Networking > LAN > IPv6 LAN Configuration and set the IPv6 Address: to "<My HE Routed /64 Prefix>::101f" (random last four characters), IPv6 Prefix Length: is set to 64, and under the DHCPv6 section, I left the DHCP Status: set to "Disable DHCPv6 Server".
So, this is all of the settings related to IPv6 that I've done in an effort to get the tunnel working. Please, if you recognize something that I've done wrong, please let me know.