Date: Wed, 16 Jan 2002 17:18:09 -0800 From: "Crist J . Clark" <cjc@FreeBSD.ORG> To: "Reto Trachsel (NetModule)" <reto.trachsel@netmodule.com> Cc: "'net@freebsd.org'" <net@FreeBSD.ORG> Subject: Re: ICMP Redirect Message-ID: <20020116171809.E35910@blossom.cjclark.org> In-Reply-To: <F58DFF990DB0D411841D000102A7CD70090BFA@tigris.pacific>; from reto.trachsel@netmodule.com on Wed, Jan 16, 2002 at 01:15:54PM %2B0100 References: <F58DFF990DB0D411841D000102A7CD70090BFA@tigris.pacific>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, Jan 16, 2002 at 01:15:54PM +0100, Reto Trachsel (NetModule) wrote:
> Hi All
>
> I have some problems with ICMP Redirect. I'm using a FreeBSD-4.5-RC machine
> as default Rrouter for our network. If i'm doing a ping to an external host,
> a ICMP Redirect message is sended by the router-machine, but not only
> once... it is sended every time a ICMP echo-request is detected. The Host
> doesn't enter the route from the ICMP redirect into his table. With other
> Systems (ie RH Linux and CISCO Routers), this will work on this host
> correctly.
I am a little unclear on this. Is "router-machine" the FreeBSD router
in question? What kind of machine is "Host?" Are we trying to get
"router-machine" to stop sending redirects? Or are we trying to get
"Host" to accept and use the redirects?
> Is there a posibility to switch on/off the ICMP redirect? How can i
> configure, which hosts to redirect?
You can turn sending/receiving redirects on and off with sysctl(8),
but not on per-host basis. You could simulate this behavior to some
degree using firewalling.
> I saw the configs for sysctrl, but no way to enable or disable the sending
> of these packets. Du you have an idea?
>
> net.inet.icmp.drop_redirect = 0
A machine will ignore incoming redirects. If you want "Host" to use
the redirects, set this to one.
> net.inet.icmp.log_redirect = 1
This logs the event.
The other sysctl(8) you may be interested in is,
net.inet.ip.redirect
Which controls whether a router sends redirects.
--
Crist J. Clark | cjclark@alum.mit.edu
| cjclark@jhu.edu
http://people.freebsd.org/~cjc/ | cjc@freebsd.org
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20020116171809.E35910>