Nightly disk-related panic since upgrade to 10.3

[Andrea Venturoli]

On 10/20/16 22:12, Peter wrote:

Hello.



> Basically You have two options: A) fire up kgdb, go into the code and
> try and understand what exactly is happening. This depends
> if You have clue enough to go that way; I found "man 4 gdb" and
> especially the "Debugging Kernel Problems" pdf by Greg Lehey quite
> helpful.

I've tried this way, but altough I'm quite proficient with [k]gdb I tend 
to get lost in FreeBSD's kernel's source code, which, unfortunately, I'm 
not familiar with.

BTW, I had read that book years ago; I searched for it now, but a 2005 
edition still comes up. Has it ever been updated?





> B) systematically change parameters. Start by figuring from the logs
> the exact time of crash and what was happening then, try to reproduce
> that. Then change things and isolate the cause.

Again, I already tried, but without luck.

Since I had one hang one night during the creation of a snapshot, 
yesterday I tried creating/deleting around 40 of them: I hoped to get 
the system to hang again, but it all worked perfectly.

Since backups are run at night (possibly at the time of the hangs/panics 
and doing snapshots), I launched several backup jobs, but they all 
worked perfectly.

I checked that at the times of the panics there is usually no cron job, 
periodic job or whatever. At least not something I could identify.
There was in fact once a periodic running, but that's not the rule.
"ps -axl -M /var/crash/vmcore.x" showed nothing unusual.




  bye & Thanks
	av.