From owner-freebsd-isdn Tue Nov 24 19:16:14 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id TAA16084 for freebsd-isdn-outgoing; Tue, 24 Nov 1998 19:16:14 -0800 (PST) (envelope-from owner-freebsd-isdn@FreeBSD.ORG) Received: from castor2.freiepresse.de (castor2.freiepresse.de [194.25.232.30]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id TAA16078 for ; Tue, 24 Nov 1998 19:16:10 -0800 (PST) (envelope-from G.Sittig@abo.FreiePresse.DE) Received: from speedy.gsinet (ppp-pln172.freiepresse.de [194.25.234.172]) by castor2.freiepresse.de (8.8.4/8.8.4) with ESMTP id EAA17943; Wed, 25 Nov 1998 04:07:57 +0100 (MET) Received: from speedy.gsinet (sittig@speedy.gsinet [192.168.10.129]) by speedy.gsinet (8.8.8/8.8.8) with SMTP id BAA29171; Wed, 25 Nov 1998 01:24:49 +0100 Date: Wed, 25 Nov 1998 01:24:49 +0100 (CET) From: Gerhard Sittig X-Sender: sittig@speedy.gsinet To: Malte Lance cc: freebsd-isdn@FreeBSD.ORG Subject: Re: isppp + dynamic IP In-Reply-To: <199811240902.KAA04341@neuron.webmore.prv> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-isdn@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Tue, 24 Nov 1998, Malte Lance wrote: > On 23 Nov, Gerhard Sittig wrote: > > Wait a minute ... > > ... were we talking about dynamic-assigned local IP-addresses > on the interface ??? > > I was under that impression. > If you were talking about something else, then sorry, ... i missed > the topic. > Otherwise: > dynamic-assigned IP-addresses are configured with isdn4bsd by > assigning 0.0.0.0 as the local address on the isdn-interface. > When assigning some other address as the local part to the interface, > the sppp-code insists on getting exactly that address from the peer. > If the peer does not agree on that, IPCP does not come up. Oh, sorry. Since ISDN support is somewhat new in FreeBSD (at least in its current form of i4b, I don't know much about the previous version since it didn't work for me) I have been using linux for some years now. And since one doesn't touch a running system without any strong need I have to admit I never had any further tests with ISDN under BSD since i4b came up. I just follow these lists (announce and freebsd-isdn) because one day i MIGHT want to change to BSD at least on the serving machines (that should be transparent for anyone since I won't touch any workstation). So I beg your pardon for my ignorance for the internals and details. To cut it short: I didn't know about that convention since in Linux you can setup your interfaces however you please and ipppd (a derivate of pppd) reconfigures your interface in case IPCP negotiation did take place (of course you can configure whether you accept these or assume a fix setup). > Some months ago i've written the changes to the sppp-code to enable > dynamic-IP-adr-assignment by just giving spppcontrol a command-line- > flag, instead of setting the local address to 0.0.0.0. So you got > the freedom to set it to any local IP-address without disabling the > dynamic-IP-address-assignment. Since nobody on this list was really > interested in the changes, i did not bother Hellmuth with the patches. That's what i4l does by default. So you have configured interfaces with IP addresses you have to be able to resolve in reverse queries when issuing commands like "netstat" and "route". And once you were dialing up to your ISP and hanging up you have an address assigned to an interface you don't know (unless you run a local named). That's when "normal" commands trigger another dialup due to the DNS query, you get this answer, but you then own a different address which you again don't know and start it over again and again and ... Given the prices here in Germany this really is annoying AND expensive, too. > > one for the interface it triggers dialing. Upon negogiation > > ipppd does something like > > ifconfig ippp0 down > > ifconfig ippp0 inet $MYDYNIP pointopoint $HISDYNIP up > > route add default dev ippp0 > > ["ifconfig isppp0 down" hangs up the line] The above was pseudo code to demonstrate the behaviour of ipppd and why previous routes through this interface get lost (and have to be reestablished by a hooked in script upon ip-up and ip-down). > Here is what i said: > "In short, until the interface has not been assigned > the dynamic IP-adr, the outgoing packets get a source-IP > of 0.0.0.0" Now that you corrected my mistake we DO agree here :) > >> [ ... tcp sessions bound to obsolete address ... ] > > > > That's quite another problem, but it never puzzled me since it > > doesn't apply to routers and firewalls -- they just forward their > > packets and don't serve as a source for telnet sessions :) > > Good enough for you (tm) ;) > What about proxies/caches (WWW/FTP/...) ? That's the kind of software i DON'T run on firewalls :) In general I don't do ANYTHING there besides ssh from the internal LAN for administrative purposes. And while I feel that ANY network should protect its dialup connection I don't see a need for dialups doing a TCP session originating from themselves. G.Sittig@abo.FreiePresse.DE -- If you don't understand or are scared by any of the above ask your parents or an adult to help you. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-isdn" in the body of the message