Finding out the hard way is not always a bad thing. I think you got a better 
way of understanding than just "finding the answer" without having to search 
for it.

Holger

> -----Original Message-----
> From: Georgi Petrov [mailto:[EMAIL PROTECTED]
> Sent: Monday, September 04, 2006 11:19 AM
> To: [email protected]
> Subject: Re: [pfSense-discussion] pfSense and TTL (time to live) = 1
> 
> 
> Wow!
> 
> I'm stupid :(
> 
> 2 days lost in researching how to do it my way with m0n0wall :( Well,
> may be not - these were my first steps in BSD :)
> 
> On 9/4/06, Scott Ullrich <[EMAIL PROTECTED]> wrote:
> > On 9/4/06, Georgi Petrov <[EMAIL PROTECTED]> wrote:
> > > Hello everybody,
> > >
> > > I've sent this feature request to the m0n0wall mailing 
> list, so it's a
> > > copy-paste. Everything written can be applied to pfSense as well!
> > >
> > >
> > >
> > > Here in Bulgaria we love m0n0wall and many people use it for home
> > > routing purposes. Our internet is delivered by LAN cables (insane,
> > > isn't it?) and some of my smarter friends split the service to the
> > > neighbours. This is pretty cool because you have to pay 
> 2-3 times less
> > > and believe me - Bulgaria isn't the cheapest place to live in ;)
> > >
> > > Ok, you would say - you put one m0n0wall router under 
> your bed and pay
> > > 2 times less for internet (as well as your neighbours). What's the
> > > problem? Here comes the problem: Almost all ISPs in 
> Bulgaria modify
> > > the TTL (time to live) value of all incoming packets to 1, so when
> > > they enter the m0n0wall router, it decrements the TTL to 
> 0 and being
> > > zero, the packet gets dropped (and doesn't reach any of 
> the computers
> > > in the local network).
> > >
> > > There is a very simple way to work around that. The FreeBSD kernel
> > > should be compiled with IPSTEALTH option enabled. This is 
> absolutely
> > > harmless and does the following:
> > >
> > > When the kernel is compiled with this option, later you 
> can set one
> > > sysctl variable to "1" (enabled), which will turn on the IPSTEALTH
> > > mode. In this mode the router "hides" itself, becomes 
> intraceable with
> > > tracert and the most important thing is that it doesn't 
> decrement the
> > > TTL, so the little trick played by most ISP becomes irrelevant.
> > >
> > > This is completely harmless to m0n0wall - it won't be enabled by
> > > default, nothing will change for the default install, but this
> > > functionality will be present for whoever need it! May be later a
> > > "checkbox" could be added in the webGUI for easier accessibility.
> > >
> > > I already run m0n0wall's FreeBSD IPSTEALTH enabled kernel 
> and enabling
> > > IPSTEALTH in running m0n0wall is as easy as adding
> > >
> > > <shellcmd>sysctl net.inet.ip.stealth=1</shellcmd>
> > >
> > > just before
> > >
> > > </system>
> > >
> > > The whole procedure is explained by another smart 
> bulgarian on this
> > > page (bulgarian language):
> > > http://hardwarebg.com/forum/showthread.php?t=76480&highlight=TTL
> > >
> > > So - this way the whole problem is solved and the day - saved ;)
> > >
> > > I ask for one simple thing - could you please enable 
> IPSTEALTH in the
> > > next m0n0wall release, please! It's a great 
> router/firewall - make it
> > > even better!
> > >
> >
> > # sysctl -a | grep stealth
> > net.inet.ip.stealth: 0
> > net.inet6.ip6.stealth: 0
> >
> > It's already compiled in.
> >
> > Have fun!
> >
> > Scott
> >
> 

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