Re: obtaining a kernel crash dump
Nick Strebkov writes: May 19 16:17:00 devel /kernel: May 19 16:17:00 devel /kernel: syncing disks... 60 3 2 [dd boot kernel messages] Try disabling sync-on-panic. It almost always causes problems for me when trying to get dumps. % cat /etc/sysctl.conf kern.sync_on_panic=0 If you are running a newer version of FreeBSD with the DDB_TRACE options, you want to enable DDB and DDB_TRACE. This will get you a stack trace on console, which is a heck of a lot better than nothing if your crashdumps don't work. options DDB #Enable the kernel debugger options DDB_TRACE Sometimes I have problems getting a dump on 5.x if I've dropped into ddb, so I use the following to prevent the system from dropping to a DDB prompt at panic: options DDB_UNATTENDED Drew ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: obtaining a kernel crash dump
On Wed, May 19, 2004 at 05:20:04PM +0300, Peter Pentchev wrote: On Wed, May 19, 2004 at 04:34:42PM +0300, Nick Strebkov wrote: Hi there. I can't obtain a crash dump. % cat /sys/i386/conf/DEVEL | grep makeoptions makeoptions DEBUG=-g % cat /etc/rc.conf| grep dump dumpdev=/dev/ar0s1b dumpdir=/var/crash I'm testing my kernel patch and the following is what I see in /var/log/messages: Can you force the kernel to dump by using DDB? Place 'options DDB' in your kernel config, then, when the system is quiescent, hit Ctrl-Alt-Esc and type 'panic' at the DDB prompt. If this works, and you get a crash dump, then the problem might be that with your kernel patch, the kernel is panicking in a low-level layer, like memory management or disk drivers or something like that, and it simply cannot make a crash dump, since that would mean invoking code that depends on bad data or something. Thanks a lot. I'll try. I modify the ip_input.c in the manner like IPFW do. -- Nick Strebkov Public key: http://humgat.org/~nick/pubkey.txt fpr: 552C 88D6 895B 6E64 F277 D367 8A70 8132 47F5 C1B6 ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to [EMAIL PROTECTED]
Re: obtaining a kernel crash dump
On Wed, May 19, 2004 at 04:34:42PM +0300, Nick Strebkov wrote: Hi there. I can't obtain a crash dump. % cat /sys/i386/conf/DEVEL | grep makeoptions makeoptions DEBUG=-g % cat /etc/rc.conf| grep dump dumpdev=/dev/ar0s1b dumpdir=/var/crash I'm testing my kernel patch and the following is what I see in /var/log/messages: Can you force the kernel to dump by using DDB? Place 'options DDB' in your kernel config, then, when the system is quiescent, hit Ctrl-Alt-Esc and type 'panic' at the DDB prompt. If this works, and you get a crash dump, then the problem might be that with your kernel patch, the kernel is panicking in a low-level layer, like memory management or disk drivers or something like that, and it simply cannot make a crash dump, since that would mean invoking code that depends on bad data or something. G'luck, Peter -- Peter Pentchev [EMAIL PROTECTED][EMAIL PROTECTED][EMAIL PROTECTED] PGP key:http://people.FreeBSD.org/~roam/roam.key.asc Key fingerprint FDBA FD79 C26F 3C51 C95E DF9E ED18 B68D 1619 4553 Hey, out there - is it *you* reading me, or is it someone else? pgpx3Sb7VsHMD.pgp Description: PGP signature
Re: obtaining a kernel crash dump
On Wed, May 19, 2004 at 04:34:42PM +0300, Nick Strebkov wrote: I can't obtain a crash dump. Can you, on a clean -current, break into DDB and force a panic by simply typing panic ? Please report whether the kernel dumps core in this case. Some systems have problems with ATA that prevents them from dumping. Mark ___ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to [EMAIL PROTECTED]
