From owner-freebsd-hackers Sat Jul 1 13:44:14 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id NAA01349 for hackers-outgoing; Sat, 1 Jul 1995 13:44:14 -0700 Received: from mail.htp.com (mail.htp.com [199.171.4.2]) by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id NAA01342 for ; Sat, 1 Jul 1995 13:44:11 -0700 Received: from et.htp.com (et.htp.com [199.171.4.228]) by mail.htp.com (8.6.5/8.6.5) with SMTP id QAA16995; Sat, 1 Jul 1995 16:42:45 -0400 Date: Sat, 1 Jul 1995 16:42:45 -0400 Message-Id: <199507012042.QAA16995@mail.htp.com> X-Sender: dennis@mail.htp.com X-Mailer: Windows Eudora Version 2.0.3 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" To: =?KOI8-R?Q?=E1=CE=C4=D2=C5=CA_=FE=C5=D2=CE=CF=D7?= aka "Andrey A. Chernov, Black Mage" From: dennis@et.htp.com (dennis) Subject: Re: Watchdog/Hard Reboot for BSD UN*X Cc: freebsd-hackers@freebsd.org Sender: hackers-owner@freebsd.org Precedence: bulk >Andrey A. Chernov writes.... >>The ET/WDT is an ISA card with a hardware timer that wires directly into >>the reset switch on the pc and can reset the PC just as if you pressed the >>reset button. The watchdog timer can detect system hangs in seconds instead >>of hours. > >The question is: what happens for soft reboot? >I.e. if program just use reboot() syscall? >Bad assumption is: system reboots, watchdog don't receive his >tics anymore and goes to reboot timeout, system start to load, >and in the middle of system loading watchdog issue reset, >so system boots again... >-- some rather simple remedies off the top of my head.... 1) redefine the reboot function to be a halt (in which case the timer will reboot the system once it is halted) 2) Set the timer for a value that is larger than the amount of time it takes to reboot, and then disable/re-enable the timer from your startup script. db