I have been playing around with a couple of debian "Lenny" boxes (kernel
2.6.25-2) to experiment with isatap.

I have one box running as server and that works OK. When using windows
XP clients, it works without problem.
(based on the information found here: http://v6web.litech.org/isatap/

I now want to try it with a linux-box as isatap client.
Problem is that the "ip" command seams not to be fully extended to
support isatap.
When you enter the command "ip tunnel add is0 mode isatap local
V4ADDR_NODE v4any V4ADDR_RTR ttl 64", the option "v4any" is unknown.

I kind of managed to get part of it done, using this:
ip tunnel is0 mode isatap local V4ADDR_NODE ttl 64
ip link set is0 allmulticast on
ip -6 route add default via fe80::5efe:V4ADDR_RTR dev is0
ip link set is0 up

When I a tcpdump in the "is0" interface, I do see traffic, including
multicast; however there no "router sollicitation" messages are sent out
by the client; so the client does not receive a RA message from the
isatap server, and -hence- does not configure a public IPv6 address.

It there a way to force to "router sollication" in a (isatap) tunnel?

There is a sysctl-setting "net.ipv6.conf.is0.router_sollicitation" which
is by default set to 0. Changing it to some other value does not change

Of course, I can configure the tunnel manually using "ip -6 address add"
...., but -if possible- I would like tunnel to be configured
automatically. (after all, that what's the "A" in "isatap" stands for,
doesn't it? :-)

Cheerio! Kr. Bonne.