Date: Fri, 6 Apr 2012 11:13:21 -0700 From: Devin Teske <devin.teske@fisglobal.com> To: "'gahn'" <ipfreak@yahoo.com>, "'freebsd general questions'" <freebsd-questions@freebsd.org> Subject: RE: learning freebsd kernel Message-ID: <08b701cd1420$f4e21a60$dea64f20$@fisglobal.com> In-Reply-To: <1333735492.43069.YahooMailNeo@web130205.mail.mud.yahoo.com> References: <1333735492.43069.YahooMailNeo@web130205.mail.mud.yahoo.com>
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> -----Original Message----- > From: owner-freebsd-questions@freebsd.org [mailto:owner-freebsd- > questions@freebsd.org] On Behalf Of gahn > Sent: Friday, April 06, 2012 11:05 AM > To: freebsd general questions > Subject: learning freebsd kernel >=20 > hi gurus: >=20 > how could i create the core dumps on freebsd kernel? i am trying to creat= e a > kernel core dump on 8.1 but it didn't happen: >=20 > # sysctl -w debug.kdb.panic=3D1 >=20 > well the system went panic, entered the mode db>. i did "reboot' but ther= e was > no core/kernel dumps under /var/crash. >=20 Did you set the "dumpdev" directive in /etc/rc.conf? % grep dumpdev /etc/defaults/rc.conf dumpdev=3D"NO" # Device name to crashdump to (or NO). savecore_flags=3D"" # Used if dumpdev is enabled above, and present. You should set the value of dumpdev to your swap device. You can get this value by executing the following: awk '$3~/swap/{print $1}' /etc/fstab Should produce something like "/dev/mfid0s1b" or "da0s1b" or "ada0s1b" or "ad0s1b" etc. depending on your RELEASE and hardware. If the output is, for example, "/dev/mfid0s1b", you should add the followin= g to /etc/rc.conf: dumpdev=3D"/dev/mfid0s1b" --=20 Devin > the customized kernel has those information enabled: >=20 > # Debugging for use in -current > options=A0=A0=A0=A0=A0=A0=A0=A0 KDB=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0=A0=A0=A0 # Enable kernel debugger support. > options=A0=A0=A0=A0=A0=A0=A0=A0 DDB=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0=A0=A0=A0 # Support DDB. > options=A0=A0=A0=A0=A0=A0=A0=A0 GDB=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0= =A0=A0=A0=A0=A0=A0=A0=A0 # Support remote GDB. >=20 > user@host:~:$ sysctl -a | grep debug.kdb > debug.kdb.stop_cpus: 1 > debug.kdb.trap_code: 0 > debug.kdb.trap: 0 > debug.kdb.panic: 0 > debug.kdb.enter: 0 > debug.kdb.current: ddb > debug.kdb.available: ddb >=20 >=20 >=20 > by the way, where is my gdb? on one of my company's machisne, it looks li= ke > this: >=20 > debug.kdb.available: ddb gdb >=20 > thank you all >=20 > /gahn > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.o= rg" _____________ The information contained in this message is proprietary and/or confidentia= l. If you are not the intended recipient, please: (i) delete the message an= d all copies; (ii) do not disclose, distribute or use the message in any ma= nner; and (iii) notify the sender immediately. In addition, please be aware= that any message addressed to our domain is subject to archiving and revie= w by persons other than the intended recipient. Thank you.
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