F13: IPv6 tunnel question/problem

[Kevin J. Cummings]

The other day, I had my cable modem drop its connection to the internet.
 Ah, if I had only noticed it when it happened, instead, I played with
the network service on my home server first by issuing:

service network restart

The message that came back (and still does when I use that command, or
when I reboot the system) is:

> Global IPv6 forwarding is disabled in configuration, but not currently disabled in kernel
> Please restart network with '/sbin/service network restart'
> Given IPv4 address '192.168.6.94' is not globally usable.
> 6to4 configuration is not valid

Huh?  I had a working 6to4 tunnel up and running before my ISP's modem
required resetting.  Now, all I see is this message, and my 6to4 tunnel
no longer works.

How do I know this is the problem?  Because last week, I successfully
ran the tests on the World IPv6 test day WWW site and passed 100%.

I have this F13 server, and F14 test machine, and my F14 laptop
configured with an IPv6 /48 network addresses (and the server also has a
/64 address for use in the IPv6 tunnel), and I routinely ssh to the IPv6
names within my network, and I have also (from time to time) surfed to
some IPv6 web sites from my laptop (explicitly routing through the
tunneling server).

Now, I'm getting massive delays (which I suspect is due to the
mis-configured IPv6 stuff timing out before trying IPv4 addresses) on
both IPv6 and IPv4 stuff.

I can no longer use IPv6 to ping the remote end of my IPv6 tunnel (but I
can ping the local end), but it responds to pings to the tunnel's IPv4
remote address just fine.

All IPv6 traffic within my local network seems to work just fine.

My server opens the tunnel at its end, routes through my linksys router
to my ISP's router to the internet.  Both the ISP router and my linksys
router are configured to put my F13 server in their DMZ, which makes my
F13 server equivalent to having my dynamic IP address of my outside
world connection.  (No criticisms, please.  This has been working just
fine since early January when I switched ISPs, and a similar
configuration was working just fine before that with my old ISP.)

I guess my first question is:  Where does Fedora think that Global IPv6
forwarding is "disabled in configuration"?  What file?  What
configuration option?

My second question is:  Why is this broken now when it wasn't before?
Did some update break this?  Did changing from an i686 kernel to a
PAE.i686 kernel break this?  (Just wait until my next upgrade when I
change from i686 to x86_64!)

Its just the IPv6 tunnel that appears to be broken....  Of course, that
means that I no longer have IPv6 connectivity to my server that used to
have....

-- 
Kevin J. Cummings
kjchome at verizon.net
cummings at kjchome.homeip.net
cummings at kjc386.framingham.ma.us
Registered Linux User #1232 (http://counter.li.org)