[ds6] IPV6 setup questions

[Walter Dnes]

Hello to the list;

  I'm a computer hobbyist who's been using linux for over 4 years, and
want to get familiar with IPV6 now.  Having used Gentoo linux for
several months, I decided to take my "hot backup machine", and reinstall
Gentoo from scratch, with things tweaked differently.  One of those
differences was enabling IPV6.  I've followed  the instructions at
http://www.gentoo.org/doc/en/ipv6.xml up to the part where it checks
that lo is working, and I've also rebuilt programs that take advantage
of IPV6.  Here's what I get...

[m1800][root][~]ip -6 addr show lo
2: lo: <LOOPBACK,UP> mtu 16436
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever

[m1800][root][~]ip -6 addr show eth0
1: eth0: <BROADCAST,MULTICAST,UP> mtu 1454 qlen 1000
    inet6 fe80::250:baff:fee7:ebfa/64 scope link
       valid_lft forever preferred_lft forever


  The Gentoo "mirrorselect" utility in the 2004.3 profile claimed to
find IPV6 mirrors before the install process got to the chroot part.
I'm rather sceptical of that, especially since I'm on ADSL hooked up
via a 4-port combination modem/router which is all IPV4.  A broken
mirrorselect script could be the explanation.  Questions...

  1) How do I test my ISP's IPV6 readiness (or lack thereof)?  I'll
probably have to go via a tunnel-broker, but just in case I don't have
to, I'd like to find out before setting up with a tunnel broker.

  2) Is a static IP address required for tunnelling?  I'm currently
running on a dynamic IP address, but I can get a static address if it's
really necessary.

  I'm rather foggy on IPV4 and IPV6 co-existance.

  3) Is the machine running IPV4 and IPV6 in parallel, or is it running
IPV6-only, of which IPV4 is a subset?  A more specific question might
be... do I have to run both iptables and ip6tables simultaneously, or
can everything be handled by ip6tables?  Since the IPV4 address
1.2.3.4 ==> IPV6 address ::ffff:1.2.3.4/96, does that mean that IPV4
192.168.0.0/16 maps to ::ffff:192.168.0.0/80 ?

  4) I'll obviously still want to be able to surf the IPV4 web and use
other IPV4 internet services, plus I still want to be able to scp
backups to my main machine (IPV4).  My setup should be planned to allow
this.

-- 
Walter Dnes <waltdnes at waltdnes.org>
An infinite number of monkeys pounding away on keyboards will
eventually produce a report showing that Windows is more secure,
and has a lower TCO, than linux.