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To: Matthew Seaman <matthew@FreeBSD.org>
cc: freebsd-hackers@freebsd.org
Subject: Re: Catching core files in read-only jails
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From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
References: <CABXB=RTHetL-mjehjSaTVT2ipLTQySE2Y8UCUQXcM7_hWV3g_Q@mail.gmail.com>
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Date: Fri, 01 Apr 2016 09:32:39 +0000
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--------
In message <56FE13BA.4060500@FreeBSD.org>, Matthew Seaman writes:

>> If an application is running on a production server in a read-only
>> jail for security purposes, and it crashes occasionally due to some
>> unknown bug, is there any way to catch a core file?
>
>You'll have to mount a read-write filesystem somewhere in your jail and
>configure core dumps to be written to that filesystem.  Something like
>this example from core(5):

It would be really nice if instead of coredumps one could select to
just get a stack backtrace.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.