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Newsgroups: comp.os.386bsd.questions Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!agate!howland.reston.ans.net!europa.eng.gtefsd.com!uunet!nih-csl!postman From: crtb@helix.nih.gov (Chuck Bacon) Subject: SLIP difficulties Message-ID: <1993Nov17.130816.6937@alw.nih.gov> Sender: postman@alw.nih.gov (AMDS Postmaster) Organization: National Institutes of Health, Bethesda Date: Wed, 17 Nov 1993 13:08:16 GMT Lines: 66 This appears to be a problem between Cisco and FreeBSD -- perhaps a misunderstanding of the Van Jacobson protocol (?), although I got no response at all when I tried NOT using VJHC! Dialing in via Kermit (escaping and hitting ^Z), to a Cisco terminal server which is configured for slip unnumbered, and passive Van Jacobson header compression, and trying to make it all work. It tells me my IP address, and I do: slattach sl0 -c -h -s 19200 /dev/tty00 (force VJHC, RTS/CTS flow) ifconfig inet xx.xx.xx.xx netmask 0xfffffe00 up (I've also tried with -trailers, but that didn't work AT ALL) route add (what?) An interesting feature is the unnumbered option, in which my IP address is on the same subnet (ethernet) as the Cisco, and there is only one IP address. That is, the Cisco has its own IP address on the subnet, and it assigns me one other. How do I declare my default route, when there is nobody but an ethernet translator at the other end of my point-to-point link? If I don't have a default route declared, telnet and others tell me there's no route at all. So I've been using my own IP address, or that of the Cisco, or that of a nearby router, and those all seem to work. There are some problems: 1. I can telnet and ftp to some hosts on (and off!) the local subnet, but not others. Still others say I'm connected, but I get no further response. 2. I can't ping anything except localhost. When I try, I see the modem's TxD light flash once per second, but nothing comes back on the RxD light. 3. Telnet and ftp sessions rarely, but occasionally, go full speed and quite smoothly for many seconds at a time, but almost always have long (~30 sec.?) hangups. 4. I have even telnetted to a host and ftped back from that host, but failed to transfer after successfully logging in, with the message: 425 Can't build data connection: Connection timed out 5. When I query the Cisco about SLIP statistics, it tells me that about 1/3 of the total packets were in error! HELP! It appears I'm not alone. The following, from a month ago, relates almost the identical experience-- including seeing TxD flashing, and nothing on RxD, when I ping. On Oct. 5, stas@po.EECS.Berkeley.EDU (Stan Malyshev) wrote: > I am attempting to establish a SLIP connection between a FreeBSD box > at home and a campus machine, by dialing in to a local net provider, > telnetting to campus, and then initiating SLIP on both ends, etc.. [ ... ] > slattach sl0 -a -s 38400 -r /dev/null /dev/sio01 > ifconfig inet 128.32.138.14 128.32.138.2 netmask 255.255.255.0 up > route add default 128.32.138.2 [ ... ] > Stan I'd really like to solve this one! If I get it all up and running, I'll be glad to contribute to a FAQ entry. Chuck Bacon - crtb@helix.nih.gov - 301-496-4823 "After all, computers have rights too!" - Ernst Bacon, 1898-1990 -- Chuck Bacon - crtb@helix.nih.gov ( alas, not my 3b1 )-: ABHOR SECRECY - DEFEND PRIVACY