Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!cs.utexas.edu!sun-barr!newstop!sun!amdcad!brahms!phil From: phil@brahms.amd.com (Phil Ngai) Newsgroups: comp.dcom.lans Subject: Re: Ethernet "heartbeat" Message-ID: <1991May20.165442.23834@amd.com> Date: 20 May 91 16:54:42 GMT References: <12164@uwm.edu> <1991May16.004523.21301@berlioz.nsc.com> <105002@sgi.sgi.com> Sender: usenet@amd.com (NNTP Posting) Organization: Advanced Micro Devices, Inc. Lines: 26 vjs@rhyolite.wpd.sgi.com (Vernon Schryver) writes: >decade. If these are the only machines that care, it seems to me that >heartbeat (or SQE which is not identical, but close enough) is almost >useless in real life. I think that people who understand what CSMA/CD is about try to run with SQE, but of course there are lots of sites and vendors out there who don't understand as much as they should. >I care, because I'm wondering if a bunch of BSD-style ethernet drivers I >know about should be changed to notice missing hearbeats. They did notice >about 3 years ago, but only by mistake. If they should care, where should >they report the problem? Would a printf be appreciated or cursed? Say one >printf on the first missing heartbeat? My guess is it would be cursed, >because almost all transceivers have heartbeat turned off. I would say it ought to be maintained as a statistic by the driver and accessible via ioctl. Ideally, you'd bug the system manager about no SQE, but realistically, you'd probably get calls from people who don't understand 802.3 and don't want to. As far as printf on first missing heartbeat, what does "first" mean? What if someone unplugs the AUI cable for network maintenance and then reconnects it an hour later? --