Re: [PATCH] MASQUERADE not flushing conntracks on ip change

[Patrick McHardy <kaber@trash.net>]

Harald Welte wrote:

>On Fri, Nov 05, 2004 at 12:40:03AM +0100, Henrik Nordstrom wrote:
>
>  
>
>>I am not saying that the current code is correct, only that I see no 
>>reason why MASQUERADE should consider being overly friendly to people 
>>having multiple IP addresses on their dynamic IP interface.
>>    
>>
>
>I totally agree with Henrik in this issue. But we relly need to document
>it.  Maybe printk() some warning in case somebody adds a second address
>to an interface that uses MASQUERADE (from within the notifier)?
>  
>
We only know is someone adds a true secondary address, not multiple
primaries, otherwise we could just ignore it. Anyway, I agree we
don't need to be overly friendly, I just don't see a case where this
optimization does something useful. On ethernet devices, why delete
the IP (if it didn't change) or set the interface down in the first
place ? On ppp-interfaces, it doesn't work. Phil mentioned powercycling
his dsl-/cablemodem would set his eth-interface down. I find that hard
to believe, so I assume he didn't literally meant "my", but picked a
bad example.

So, can anyone think of a setup where this optimization does work ?

Regards
Patrick