Re: use of the limiting options

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OOOOOOH - I see I think.. the ones that get caught by the limit rule don't
go to the drop rule, which means they're allowed to connect. The ones that
don't get caught by the limit rule slip on through to the drop rule.

See - my understanding of what the limit module was doing was completely
off base! Now I understand what's going on.

<EOL>
Tib

On Tue, 25 Jan 2005, Mark Moseley wrote:

> It's used very often for logging, so that the logging doesn't swamp
> the firewall's disk. Imagine you're dropping 100 packet/s and want to
> log what's going on. You'd want to have the logging rule limited to
> something like 1/s or whatever.
>
>
>
> On Tue, 25 Jan 2005 13:56:25 -0600 (CST), Tib <tib@xxxxxxxxxxxxxxx> wrote:
> >
> > You're kidding o_O
> >
> > I guess it makes sense.. the connections will trip that rule until it is
> > satisfied and then move onto the next. That's.. bizarre.
> >
> > <EOL>
> > Tib
> >
> > On Tue, 25 Jan 2005, Mark Moseley wrote:
> >
> > > Heh, forgot to CC the list on my original reply, sorry.
> > >
> > > Makes sense on the --limit-burst. :)
> > >
> > > As far as adding the DROP/REJECT after that, once the connection limit
> > > in the --limit rule has been reached, it will simply just fall through
> > > the next rule (i.e. it doesn't do any implicit DROP'ing on its own).
> > > So the rule with the --limit just matches up to the rate in --limit
> > > and then doesn't match. Without a rule later on (or a policy to
> > > DROP/REJECT), any overflow will just get accepted.
> > >
> > >
> > >
> > > > Yup - once I saw an example of someone USING the limit options it made
> > > > sense :]
> > > >
> > > > The only thing --limit-burst does is say 'you have x many free tries
> > > > before you fall under the rate limit of Y/time restrictions'.
> > > >
> > > > So on mine, you can effectively connect twice in short succession before
> > > > you are cut back to once every 10 minutes (6 per hour).
> > > >
> > > > > Be sure to add a DROP or REJECT on the same match (unless the default
> > > > > policy is already that).
> > > >
> > > > I don't follow why to do this - explain?
> > > >
> > > > <EOL>
> > > > Tib
> > > >
> > >
> >
>


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