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Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!news.mel.connect.com.au!news.mel.aone.net.au!news.netspace.net.au!news.mira.net.au!news.vbc.net!vbcnet-west!knews.uk0.vbc.net!vbcnet-gb!azure.xara.net!xara.net!news.thenet.net!news.kei.com!news.mathworks.com!news.maxwell.syr.edu!news.apfel.de!serra.unipi.it!news-ge.switch.ch!news-zh.switch.ch!ubnsrv.unisource.ch!ubnnews.unisource.ch!newssrv.ita.tip.net!masternews.telia.net!www.boras.se!newsfeed1.telia.com!newsfeed100.telia.com!cph -1.news.DK.net!dkuug!dknet!ic.dk!not-for-mail From: j e n s e n <sic@sac.ic.dk> Newsgroups: comp.unix.bsd.bsdi.misc Subject: [solved] dynamic IP-assign, and dial-PPP on demand Date: 31 Mar 1997 20:19:12 +0200 Organization: IC Lines: 73 Sender: jensen@ic.dk Message-ID: <5hov70$dem@ic1.ic.dk> References: <5gub36$765@ic1.ic.dk> NNTP-Posting-Host: ic1.ic.dk X-Newsreader: NN version 6.5.0 #3 (NOV) Xref: euryale.cc.adfa.oz.au comp.unix.bsd.bsdi.misc:6553 on 21 Mar 1997 I wrote: >I have been trying to wheedle the PPP-software on BSD/OS 3.0 >into establishing a PPP-connection to a provider on >demand. This has to be accomplished using dynamic IP-addresses >assigned by the remote side on each call. I received a couple of helpful suggestions via email. However, today I stumbled upon a solution which seems to solve the problem in a simple manner. A new? option "allow-addr-change" is supported for the ppp.sys entry. Setting this option, the following procedure does the trick: init-script: assign an arbitrary address to the interface and point the default route through it up-script: change the default route, e.g.: "route -n change default $REMOTE" This allows the remote server to assign the IP-addresses that it wants. Works for me. j e n s e n >It seems that the two requirements -- demand dialing and dynamic >address assignment -- are mutually exclusive in this implementation >... > >Is there a way to do this, or any workarounds? > >What I have tried so far is to assign the PPP interface >an arbitrary address in order to establish a default >route. This works, sort of, in that the PPP-process >waits for a packet, gets a packet, then dials, >but ends up in: > Connected... > Set PPP line disc. > ppp: cannot negotiate local IP address,peer requests 194.xxx.57.34 > >Which seems and understandable reaction, but it leaves the client >with no connection. > >I have tried to use 0.0.0.0/24 for the local side of the ppp >interface, and this works sometimes, but I am not sure about the >implications of this, and anyway it probably only works when I make an >accurate guess of the remote IP-address. The client-machine >is dialing into a pool of Livingston Portmasters and will get >a potentially different remote host for each call. > >One would be inclined to think that the set-up is a very common >one: Having a stand-alone client machine connecting to a provider using >dynamic IP address assignment, but I don't seem to be able >to find anything in the manuals, scanning for "dynamic" and >"demand", and I realize that the IP-protocol may not be geared >to accept an IP-packet for an interface without a fixed IP-address. >(On the other hand, Windows PCs seem to be capable of this, >but maybe they are "cheating") > >Any suggestions, or even scripts? > >Having the provider assign a static address to the client >is not an option for this specific case. > >No routing is involved, except a default route through the >dial-up-connection. > -- : j e n s e n <sic@sac.ic.dk> :