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[2001:470:1f1c:a0::2]) by smtp.gmail.com with ESMTPSA id 6sm6220554wmg.17.2021.06.17.18.47.52 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 17 Jun 2021 18:47:53 -0700 (PDT) Subject: Re: Safety harnesses To: freebsd-questions@freebsd.org References: <36522.1623959839@segfault.tristatelogic.com> From: Graham Perrin Message-ID: <6852ccf3-d316-4c54-ad81-c89697377062@gmail.com> Date: Fri, 18 Jun 2021 02:47:52 +0100 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <36522.1623959839@segfault.tristatelogic.com> Content-Language: en-GB X-Rspamd-Queue-Id: 4G5hdS4CqVz4bCY X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=gmail.com header.s=20161025 header.b=pC0zJdsG; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (mx1.freebsd.org: domain of grahamperrin@gmail.com designates 2a00:1450:4864:20::331 as permitted sender) smtp.mailfrom=grahamperrin@gmail.com X-Spamd-Result: default: False [-2.00 / 15.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; R_SPF_ALLOW(-0.20)[+ip6:2a00:1450:4000::/36:c]; FREEMAIL_FROM(0.00)[gmail.com]; TO_DN_NONE(0.00)[]; RCVD_COUNT_THREE(0.00)[3]; DKIM_TRACE(0.00)[gmail.com:+]; DMARC_POLICY_ALLOW(-0.50)[gmail.com,none]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+,1:+,2:~]; RBL_DBL_DONT_QUERY_IPS(0.00)[2a00:1450:4864:20::331:from]; FREEMAIL_ENVFROM(0.00)[gmail.com]; MID_RHS_MATCH_FROM(0.00)[]; ASN(0.00)[asn:15169, ipnet:2a00:1450::/32, country:US]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[gmail.com:s=20161025]; FROM_HAS_DN(0.00)[]; DWL_DNSWL_NONE(0.00)[gmail.com:dkim]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[multipart/alternative,text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-questions@freebsd.org]; RCPT_COUNT_ONE(0.00)[1]; SPAMHAUS_ZRD(0.00)[2a00:1450:4864:20::331:from:127.0.2.255]; NEURAL_SPAM_SHORT(1.00)[1.000]; RCVD_IN_DNSWL_NONE(0.00)[2a00:1450:4864:20::331:from]; RCVD_TLS_ALL(0.00)[]; MAILMAN_DEST(0.00)[freebsd-questions] Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-Content-Filtered-By: Mailman/MimeDel 2.1.34 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 18 Jun 2021 01:47:57 -0000 On 17/06/2021 20:57, Ronald F. Guilmette wrote: > Graham Perrin wrote: > >> The surprise, to me, was losing fifty-something seconds' worth of data >> in a kernel panic situation... > In an ideal universe, the kernel never panics. … +1 tl;dr I was (originally) aiming to get backtraces for panics, intended panics. The surprises with UFS were (originally) having no crash dumps after editing /etc/rc.conf to enable crash dumps; /usr/local/etc/sudoers empty after use of visudo; gdb not found after installing gdb; and so on. Eventually I discovered that all such losses were expected.