From owner-freebsd-questions@freebsd.org Fri Jun 12 07:20:25 2020 Return-Path: Delivered-To: freebsd-questions@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 374273319D8 for ; Fri, 12 Jun 2020 07:20:25 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.126.134]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "mout.kundenserver.de", Issuer "TeleSec ServerPass Class 2 CA" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 49jsZJ12zFz43xM for ; Fri, 12 Jun 2020 07:20:23 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from r56.edvax.de ([178.8.39.138]) by mrelayeu.kundenserver.de (mreue010 [212.227.15.167]) with ESMTPA (Nemesis) id 1MUpCz-1jJ0Rn2VWr-00QheT; Fri, 12 Jun 2020 09:20:18 +0200 Date: Fri, 12 Jun 2020 09:20:18 +0200 From: Polytropon To: David Christensen Cc: freebsd-questions@freebsd.org Subject: Re: Bug or Feature? -- Disappearing /dev/ nodes after mount Message-Id: <20200612092018.2da920b8.freebsd@edvax.de> In-Reply-To: <01fb8c1e-a9e8-816e-a2ef-2c45c721687c@holgerdanske.com> References: <86546.1591917249@segfault.tristatelogic.com> <20200612082224.9c1e3797.freebsd@edvax.de> <01fb8c1e-a9e8-816e-a2ef-2c45c721687c@holgerdanske.com> Reply-To: Polytropon Organization: EDVAX X-Mailer: Sylpheed 3.1.1 (GTK+ 2.24.5; i386-portbld-freebsd8.2) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Provags-ID: V03:K1:0ptV8t/TgUCfbCYkdIlSrbzgKRHLkOtr6QK97qhJ72CcKuSJuD5 1XbZ72IpqQcgjRCQNfEwxKBkX5f9OsVQXblt7FnHLMpfkuWBZCW/PWSscTGXsE+ilqKQH+r NSVfZ8GeFKykG2YqVLjgFgYwXzH2eR6npHEfi0pG0PMY3l+O8cq63gVwb855184jcL4ZUAm 46jZQHrKR/581BANaeXpg== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:85LxGi9J11g=:ekM9eZFTBzWVR9Rhggfrf5 PQhXLuBXMwVms5UnzAa8y5qLrAAJP9iYxckZWYl/WnrqRPjsJQU86BS3ME4PpBeXi3wjDqHkQ LVKh/lDCRZKJx8OuoGsENzBrmAhg9tqG2F0Ol7/ahFlPJ4Owan4wCwxSd5hIAAXyCeZuxTBNq 9n5pp28yuZ/ujWEDrnKvRKan/UXL7BnCYHsyLcovCsWOkBOgOq/Ipy29rn68zvm+D+YXdXW/D c9QFJoNBFIzsErnRr5j7a8vvHIIEY8ui3F97pVKrAHn18pC1lT2WFkrVYaDnusDrk6bgQXTLP 0WD0m+4HTW4I/biyezNtDpRanFfZMYSvf6MsWh6gWpIX4/ijyKErVE3cPh/QIPgIMyIuWx4dz Xvan86GdoNgbnWWY6nAM+nV8kwN1kMgGQIfooEbyRh/l8cs+7h8eoxQGCEpLlNXH0fFWArD8I WCNmTtf/WXamWXJx53nsiVaYVsfiSfguzwpePRhQlEzJ+UMMNsLjV0u9n/fpBYVlGUYwVjCnP ZXZ8QKlgH/Qvb3x4UYliKBvbu3IzbniFbed1gfCPfPJ9FDbUFuzZou44rLN/n3Qc4sX44gbrt GMPMdfx7jkU7Q/uceXQR36U9lAH/ourR9aaU2GBPmFnYuXvMNqG/tuNRuYWAO4LGsqxrQpxSi b5heRazV18vBDeWplI8UmUc5pBehiXidkrkNFaHl9IwIwmBiOUwrJ2wtzdNnA6LY1iYJpivlz tqu1DojcGyqHzy/B7u/YiB6dkcsyUnNTXexDUACY3n+e367o90YZ163m37++o9AyAyKLwZ8jf djoP7QMiSG2tuxgiChdojDg+Oi/ZAngKt+xwTjw0KSSNjBWY+D2WL1TXXWgELsv5WlEWKxW X-Rspamd-Queue-Id: 49jsZJ12zFz43xM X-Spamd-Bar: ++ Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=none (mx1.freebsd.org: domain of freebsd@edvax.de has no SPF policy when checking 212.227.126.134) smtp.mailfrom=freebsd@edvax.de X-Spamd-Result: default: False [2.65 / 15.00]; HAS_REPLYTO(0.00)[freebsd@edvax.de]; RCVD_VIA_SMTP_AUTH(0.00)[]; TO_DN_SOME(0.00)[]; MV_CASE(0.50)[]; HAS_ORG_HEADER(0.00)[]; NEURAL_HAM_SHORT(-0.61)[-0.612]; RCPT_COUNT_TWO(0.00)[2]; RECEIVED_SPAMHAUS_PBL(0.00)[178.8.39.138:received]; RCVD_TLS_LAST(0.00)[]; R_DKIM_NA(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; SUBJECT_HAS_QUESTION(0.00)[]; ASN(0.00)[asn:8560, ipnet:212.227.0.0/16, country:DE]; ARC_NA(0.00)[]; REPLYTO_EQ_FROM(0.00)[]; FROM_HAS_DN(0.00)[]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[edvax.de]; AUTH_NA(1.00)[]; NEURAL_SPAM_MEDIUM(0.47)[0.467]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_SPAM_LONG(0.40)[0.399]; MID_CONTAINS_FROM(1.00)[]; RCVD_IN_DNSWL_NONE(0.00)[212.227.126.134:from]; R_SPF_NA(0.00)[no SPF record]; RWL_MAILSPIKE_POSSIBLE(0.00)[212.227.126.134:from]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 12 Jun 2020 07:20:25 -0000 On Thu, 11 Jun 2020 23:54:55 -0700, David Christensen wrote: > On 2020-06-11 23:22, Polytropon wrote: > > On Thu, 11 Jun 2020 16:14:09 -0700, Ronald F. Guilmette wrote: > > >> Interestingly, as I have just learned, when and if the user subesquently > >> mounts the relevant partition, the corresponding `/dev/gpt/partname' node > >> will, rather unexpectedly and magically, disappear until such time as the > >> relevant partition is unmounted, whereupon it will reappear. > > >> 1) Is this behavior documented somewhere that I just failed to look at? > >> If so, where? > > > > Interesting question - I would be interested in that, too. > > See Lucas, AF3E, p. 214 "GEOM Withering" [1]. Wow, thanks for providing the term. techn. "GEOM Withering", which leads to usable search results, for example: This GEOM names appearing and disappearing is the consequence of *GEOM withering. A GEOM can be used in three different ways: - reading - writing - with exclusive access The latter is the cause of GEOM withering: once a disk is mounted an exclusive lock is required to inform the other available GEOM providers that the disk is in-use. GEOM therefore withers the other disk available names, that results in the names to disappear from the dev filesystem. For more information see g_wither_geom(9) and geom(4) ORPHANIZATION example. Source: https://fluca1978.github.io/2017/10/05/FreeBSD-Wither.html And from that point, local documentation at "man 4 geom" says: ORPHANIZATION is the process by which a provider is removed while it potentially is still being used. [...] When a provider is orphaned, this does not necessarily result in any immediate change in the topology: any attached consumers are still attached, any opened paths are still open, any outstanding I/O requests are still outstanding. with an explanation of what happens, with additional info found in "man 9 g_wither_geom". Today I learned. ;-) -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ...