From owner-freebsd-bugs Tue Oct 15 10:27:56 1996 Return-Path: owner-bugs Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id KAA22235 for bugs-outgoing; Tue, 15 Oct 1996 10:27:56 -0700 (PDT) Received: from typhoon.dial.pipex.net (typhoon.dial.pipex.net [158.43.128.46]) by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id KAA22230 for ; Tue, 15 Oct 1996 10:27:52 -0700 (PDT) Received: from gazebo.candler.demon.co.uk by typhoon.dial.pipex.net (8.7.5/) id SAA27798; Tue, 15 Oct 1996 18:26:52 +0100 (BST) Received: (from brian@localhost) by gazebo.candler.demon.co.uk (8.6.12/8.6.9) id OAA00334; Tue, 15 Oct 1996 14:40:39 +0100 From: Brian Candler Message-Id: <199610151340.OAA00334@gazebo.candler.demon.co.uk> Subject: IP bugs in FreeBSD 2.1.5 To: bugs@freebsd.org Date: Tue, 15 Oct 1996 14:40:37 +0100 (BST) Cc: nato-ws@ripe.net, t12@psg.com X-Mailer: ELM [version 2.4 PL24] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-bugs@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Dear FreeBSD team, I have just returned from a NATO-sponsored Advanced Networking Course held in St Petersburg, Russia, where I was the chief instructor. For our PC-based practical sessions we used FreeBSD 2.1.5. We uncovered a number of bugs in the TCP/IP code, which I would like to report in the hope they can be fixed in some future release. 1. On several occasions we found that although a default route appeared to be in the kernel forwarding table (as shown by netstat -nr), it did not work. However simply by deleting and reinserting the exact same default route, it then worked fine. I'm afraid I can't give you a set of circumstances which can cause this problem to be reproduced. 2. When you set up a ppp link, you cannot ping your own IP number locally. (This is using kernel-based ppp, with pppd to set up the link) 3. When you use ipalias to set up multiple IP addresses for an ethernet card, you cannot ping those additional IP numbers locally. 4. If you 'ifconfig down' an interface, then set up a default route via another interface, you still cannot ping the range of IP numbers which the original interface covered - presumably the kernel still tries to send them via the (downed) interface. 5. On one occasion the kernel forwarding table had a bad entry (I think a "link #1" type entry) which could not be removed, apart from by rebooting the machine. And a couple of comments which aren't really bugs as such: 6. It would make life easier if CIDR notation were used consistently. At the moment netstat -nr shows a.b.c.d/n, but you must use -net a.b.c.d -netmask w.x.y.z for ifconfig and route add. 7. The output of netstat -nr shows the arp cache as well as actual routes, which is confusing. I am unlikely to have time to look at the source code myself I'm afraid, but I hope you don't mind me submitting the notes above. Apart from these points, and "vi" dumping core a few times, FreeBSD was stable for the whole week we were using it. Thanks in advance for your attention, Brian Candler