ipfw - bandwidth throttling (sanity check!)

[Odhiambo Washington]

Hello Security guy ;)

I have tried very hard to understand ipfw just for the purpose of
bandwidth throttling for smtp service.

Basically, I want to throttle the bandwidth used by my SMTP
server outbound to _anyone_ else except my ip blocks.

My Server is 1.2.3.4 and my ip blocks are a.b.c.d/19 and
e.f.g.h/20


Are the following rules sane enough?

        ipfw pipe 1 config bw 256Kbit/s
        ipfw add pipe 1 tcp from 1.2.3.4 to not a.b.c.d/19 25
        ipfw add pipe 1 tcp from 1.2.3.4 to not e.f.g.h/20 25


Any smtp traffic not to these netblocks should be throttled.
By that, I am thinking it will match everything smtp outbound
only, not inbound.


Thank you for your time.


-Wash

http://www.netmeister.org/news/learn2quote.html

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