[arch-projects] [netctl] [RFC] Flush the interface configuration in ip_unset instead of bring_interface_down.

[Thomas Bächler]

Am 16.05.2013 10:59, schrieb Jouke Witteveen:
> On Thu, May 9, 2013 at 11:53 PM, Thomas Bächler <thomas at archlinux.org> wrote:
>> Am 09.05.2013 23:29, schrieb Thomas Bächler:
>>> When switching networks in auto.action, the addresses are not flushed. This
>>> is especially problematic with stateless ipv6 autoconfigutation, as invalid
>>> IPs may stay around until their (potentially very long) lifetime has expired.
>>>
>>> bring_interface_down is always called after ip_unset everywhere else, so
>>> this change does not affect anything else.
>>
>> This may not be a good idea, since it probably flushes the link-local
>> address. I must test more.
>>
> 
> It does indeed flush the link-local address too.
> When are link-local addresses added and why is it bad to flush them?

They are added on interface creation (or maybe when bringing the
interface down/up) by the kernel. Without a link-local address, lots of
IPv6 functionality simply fails - it is permanently assigned to the
interface and never changes (you probably can change it, but I don't see
the point, unless you want to hide your MAC address somehow).

Best idea is to simply flush addresses in site, global and host scope as
I stated before. This flushed all ipv6 addresses except link-local, and
all ipv4 addresses.


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 901 bytes
Desc: OpenPGP digital signature
URL: <http://mailman.archlinux.org/pipermail/arch-projects/attachments/20130516/c1a4be12/attachment.asc>