================================================================================ Newsgroups: comp.os.os2.networking.tcp-ip,comp.protocols.tcp-ip.ibmpc,comp.unix.sys5.r4,comp.os.ms-windows.networking.tcp-ip,comp.os.ms-windows.nt.admin.networking,comp.sys.ibm.pc.hardware.networking From: orville@weyrich.com (Orville R. Weyrich, Jr.) Subject: Re: How to SLIP (or PPP) a Gateway? Message-ID: Reply-To: orville@weyrich.com References: Date: Sun, 10 Sep 1995 10:10:37 GMT I previously posted something like the following, which yielded the following results. I share the new information, but want MORE! :-) There seems to be a lot of interest in this thread, so lets keep it going! >I have been banging my head against a wall (ouch! :-) trying to get a SLIP >interface to my TCP-IP LAN. My initial efforts have been using OS/2 Warp >Internet Connect + IBM TCP/IP 2.0 + recommended patches. I can connect >to my internet provider via SLIP and to my LAN via ethernet, but I can't >get the OS/2 machine (which is dual homed -- lan0 + sl0) to route my other >machines on the lan through to the internet. For the sake of discussion, >let's talk about only three machines: > > 'bud' -- BSDI internet service provider at the > far end of my SLIP connection. > 'doc' -- OS/2 3.0 with TCP/IP 2.0 + Internet Connect. > 'btuyet' -- ESIX SVR4 ++++++++++ +++++++ +++++++ ++++++++++++++++++ | btuyet | <-lan-> | doc | <-slip->| bud |<-????->| restoftheworld | ++++++++++ +++++++ +++++++ ++++++++++++++++++ 198.49.110.1 198.49.110.3 ethernet 165.247.???.??? 165.247.1.31 slip (dynamic I.P.) >From btuyet I can ping either the sl0 or lan0 on doc, but I can't >ping bud. From doc I have full access to all services on both bud and >btuyet. I have tried everything I can think of with routed on doc, but >no dice. Does anyone know how to make this work? Solutions that run on OS/2, ESIX SVR4, Linux, FreeBSD, or a 286 PC (currently serving as a doorstop) are most appreciated. Responses from (Thanks!): Steve Doty computek.net!kf5mg (Jack Snodgrass) pristine.com.tw!rob (Robert Bageant) Mark Harwood student.uq.edu.au!cs325317 (David Vandenberg) eden.com!bestfc (bestfc) Tom Shaver laser.net!warbird Craig Sampson Summary of responses: If I am using a dynamically routed SL/IP account, my internet service provider (ISP) may not provide the proper routing. In particular, a ping originating from btuyet on my 198.49.110 subnet might be routed out to the internet as expected, but unless the ISP accepts routing information from my gateway machine ('doc'), the ping response may get lost and never make it back to me. This can be verified by watching the modem Tx light as I send the ping from btuyet. Dynamic SL/IP is a 'class D' i.p. address and by definition (?) cannot do routing. I may have to go to a dedicated SL/IP or PPP line, or at least to a non-dynamically assigned I.P. address dial-up. Linux on a 386 with 8 Meg RAM should run a dedicated SL/IP or PPP connection just fine. Win-NT and Lantastic have the same problem. Making my gateway machine into a proxy server is one possible solution. That also works as a firewall to control what traffic I allow to to/from the outside world. The proxy server would catch all requests from my internal LAN and retransmit them to the outside world using the i.p. address of my SL/IP connection. Such software may be ftp.tis.com/pub/firewalls/toolkit. The Internet Adapter (TIA) may solve my problem (servers are available for UNIX and VMS, others???). OS/2 provides a program called 'IPGATE' which enables it to route packets from other workstations through the SL/IP or PPP link. It is invoked with the command 'ipgate on' and allows other machines on the LAN to det the machine running SL/IP as their default router and then 'see' the internet. I tried it, but it had no effect for me. I can't find any documentation for it, either (anyone?). Using ipgate, routed should not be necessary, which is just as well, as it is a memory hog. If you have anything more to contribute, please e-mail and I will post a summary if I get anything more of substance. Right now, ipgate and proxy servers look the most promising. Thanks in advance, orville ================================================================================ Orville R. Weyrich, Jr. Weyrich Computer Consulting orville@weyrich.com http://www.indirect.com/www/weyrich The Constitution: The REAL 'Contract With America' If the Bill of Rights falls, the flag won't matter. Who will watch the watchers?