HEADS UP: Textdumps coming in next snapshots to aid debugging
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Thanks, I saw that right after my above post and already have half a post typed up :-)
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Great! May I suggest an auto-rotate feature, where the numbered dumps are archival copies with the highest number being the oldest log?
This way dumping a log doesn't require messing with file names, it's always going to be the one without number, while the proper re-numbering happens during the system reboot.
More importantly: this allows to set a limit on how many are archived, such that any dumps exceeding that number are being deleted in the same swoop. Otherwise there is a chance that a not too generously measured system disk fills up with these dumps with unsuspecting users…
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Well this feature isn't going to stick with the normal kernels upon release, only the dev kernels.
Adding some kind of rotation might be OK (or just a symlink to the newest one would be best) but for something that is hopefully a very rare occurrence it may not be worth the effort.
The way they are numbered now is handled by the savecore utility and that isn't something we'd want to start making custom changes it, it's just the way it works on FreeBSD. Anything we come along and change after savecore is done may alter the behavior of savecore as well… Unless we move the crash info to somewhere else (like /root/crash/) and always leave /var empty after savecore is run.
Might look into doing that at some point, but it sounds like a fair amount of effort for not a lot of gain.
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I installed 2.0-BETA5 (i386)
built on Thu Jan 27 20:55:04 EST 2011 (manual upgrade from build on 1 Jan 2011) and it crashed a few hours after installation. It stopped at bt> prompt so I gave the command call doadump to write a crash dump. On reboot I saw savecore report it was writing a crash dump. I now have a vmcore.0 in /var/crash but no textdump.tar.0.Something gone wrong?
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Sounds like the textdump code didn't initiate the ddb scripts like it should. No other errors in the boot log (way at the top before the message about writing out the core)
Though there are newer snapshots out now, they may behave differently.
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No other errors in the boot log (way at the top before the message about writing out the core)
It should be in /var/log/system.log? It wasn't in the dmesg output. /var/log/system.log went back only 8 hours (it was full of the once a minute noise from hostapd: group key handshake completed).
Looks like a "significant" sysctl variable got set on reload:
sysctl -a | grep panic
kern.sync_on_panic: 0
kdb.enter.panic=textdump set; capture on; run lockinfo; show pcpu; bt; ps; alltrace; capture off; call doadump; reset
debug.ddb.textdump.do_panic: 1
debug.trace_on_panic: 0
debug.debugger_on_panic: 1
debug.kdb.panic: 0
machdep.enable_panic_key: 0
machdep.panic_on_nmi: 1Maybe I'll upgrade to a newer snapshot in the next couple of days.
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No, the console errors I'm talking about would be way before the system log starts, they would have been echo'd to the console, not syslog.
From those sysctls it looks like it should have been OK though.
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I recently upgraded one of my home systems to pfSense 2.0-RC1 (i386) built on Mon Apr 18 23:29:41 EDT 2011. Since enabling Captive Portal I've had a few panics (kernel page faults). On every occasion the system entered the debugger displaying the dbg> prompt. I type bt and call doadump but on reboot I have not seen any textdump.tar files in /var/crash:
ls -l /var/crash
total 167018
-rw-r–r-- 1 root wheel 2 Apr 22 20:31 bounds
-rw------- 1 root wheel 485 Apr 19 23:04 info.0
-rw------- 1 root wheel 485 Apr 22 20:22 info.1
-rw------- 1 root wheel 486 Apr 22 20:31 info.2
-rw-r--r-- 1 root wheel 5 Apr 19 13:20 minfree
-rw------- 1 root wheel 68562944 Apr 19 23:04 vmcore.0
-rw------- 1 root wheel 51036160 Apr 22 20:22 vmcore.1
-rw------- 1 root wheel 71602176 Apr 22 20:31 vmcore.2more /var/crash/info.2
Dump header from device /dev/ad0s1b
Architecture: i386
Architecture Version: 2
Dump Length: 71602176B (68 MB)
Blocksize: 512
Dumptime: Fri Apr 22 20:23:32 2011
Hostname: pfsense2.example.org
Magic: FreeBSD Kernel Dump
Version String: FreeBSD 8.1-RELEASE-p2 #1: Mon Apr 18 23:21:20 EDT 2011
sullrich@FreeBSD_8.0_pfSense_2.0-snaps.pfsense.org:/usr/obj.pfSense/usr/pfSensesrc/src/sys/pfSense.8
Panic String:
Dump Parity: 2021776436
Bounds: 2
Dump Status: goodThe following sysctl variables are set:
sysctl -a | grep panic
kern.sync_on_panic: 0
kdb.enter.panic=textdump set; capture on; run lockinfo; show pcpu; bt; ps; alltrace; capture off; call doadump; reset
debug.ddb.textdump.do_panic: 1
debug.trace_on_panic: 0
debug.debugger_on_panic: 1
debug.kdb.panic: 0
machdep.enable_panic_key: 0
machdep.panic_on_nmi: 1On reading the textdump man page it looks as if I also need to do:
sysctl debug.ddb.textdump.pending=1
debug.ddb.textdump.pending: 0 -> 1
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For some reason certain systems (haven't been able to figure out which) aren't making proper textdumps. If they happen, they should be happening automatically. Try switching to a debug kernel to see if that helps:
http://doc.pfsense.org/index.php/Switching_Kernels
If not, switch back to the SMP kernel afterward.
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The system crashed again with a kernel page fault at the same PC. Despite having set debug.ddb.textdump.pending=1 it didn't reboot automatically so Ityped in the commands in kdb.enter.panic one per line and then on reboot savecore reported it was writing textdump.tar.
This system has a VIA C3 CPU and is running
dmesg
Copyright
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Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
The Regents of the University of California. All rights reserved.
FreeBSD is a registered trademark of The FreeBSD Foundation.
FreeBSD 8.1-RELEASE-p2 #1: Mon Apr 18 23:21:20 EDT 2011
sullrich@FreeBSD_8.0_pfSense_2.0-snaps.pfsense.org:/usr/obj.pfSense/usr/pfSensesrc/src/sys/pfSense.8 i386
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: VIA Samuel 2 (797.74-MHz 686-class CPU)
Origin = "CentaurHauls" Id = 0x673 Family = 6 Model = 7 Stepping = 3
Features=0x803035 <fpu,de,tsc,msr,mtrr,pge,mmx>real memory = 268435456 (256 MB)</fpu,de,tsc,msr,mtrr,pge,mmx>I'll switch to a debug kernel as suggested.
