In article [ref] (at Thu, 23 Sep 2004 10:07:25 +0200), Andre Tomt [off-list ref] says:

quoted

If I boot with net.ipv6.conf.default.forward = 1 in sysctl.conf - but 
then after the boot do echo 1 > /proc/sys/net/ipv6/conf/all/forward (to 
actually get it running)

we'll crash and burn when taking down the interface.

Only setting /proc/sys/net/ipv6/conf/all/forward = 1, but never touch 
default, it goes down cleanly.

I have the ipv6/conf/default/forwarding set in sysctl.conf on all the 
routers, and it seems zebra sets the ipv6/conf/all/forwarding later on.

Possibly important note:

if I set up both conf.all and conf.default (order does not matter) 
before the tunnel devices are created, everything works as expected.

eg. in sysctl.conf:
net.ipv6.conf.default.forwarding=1
net.ipv6.conf.all.forwarding=1

if default is set first, then tunnels created, followed by setting 
"all"; everything breaks down on ifdown.

pretty neat :)

Thank you everyone for tracking down this bug.
I will fix this bug and come up with patch tomorrow (or so).
Thanks again.

-- 
Hideaki YOSHIFUJI @ USAGI Project [off-list ref]
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