no crash dump generated

[Roberto Nunnari]

Hi.

A couple of days ago I upgrades the system and a few ports on
a 5.3 box and since then I'm often getting crashes.

-bash-2.05b# uname -a
FreeBSD jupiter.noonlights.net 5.3-RELEASE-p5 FreeBSD 5.3-RELEASE-p5 #0: 
Sun Feb 13 22:56:47 CET 2005 
root at jupiter.noonlights.net:/usr/obj/usr/src/sys/JUPITER  i386

I'd like to get a crash dump and so
I added the following lines to /etc/rc.conf
dumpdev="/dev/ad0s1b"
dumpdir="/usr/crash"

-bash-2.05b# ls -ld /usr/crash/
drwx------  2 root  wheel  512 Feb 16 11:17 /usr/crash/

but I'm not getting any dump! /usr/crash is always empty.

..and the machine crashes quite often:
-bash-2.05b# last|grep reboot
reboot           ~                         Wed Feb 16 20:04
reboot           ~                         Wed Feb 16 19:17
reboot           ~                         Wed Feb 16 18:40
reboot           ~                         Wed Feb 16 17:26
reboot           ~                         Wed Feb 16 14:07
reboot           ~                         Wed Feb 16 12:39
reboot           ~                         Wed Feb 16 11:30
reboot           ~                         Wed Feb 16 10:27
reboot           ~                         Wed Feb 16 09:31
reboot           ~                         Wed Feb 16 09:16

What do I miss? Do I need some kernel option?

Best regards.
-- 
               Roberto Nunnari -software engineer-
                mailto:roberto.nunnari at supsi.ch
  Scuola Universitaria Professionale della Svizzera Italiana
              Dipartimento Tecnologie Innovative
                   http://www.dti.supsi.ch
  SUPSI-DTI
  Via Cantonale                        tel: +41-91-6108561
  6928 Manno                 """       fax: +41-91-6108570
  Switzerland               (o o)
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