From owner-freebsd-questions@freebsd.org Thu Jun 21 16:48:34 2018 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id D43271023D12 for ; Thu, 21 Jun 2018 16:48:34 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.126.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "mout.kundenserver.de", Issuer "TeleSec ServerPass DE-2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 3B1D08491A for ; Thu, 21 Jun 2018 16:48:33 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from r56.edvax.de ([92.195.97.38]) by mrelayeu.kundenserver.de (mreue004 [212.227.15.167]) with ESMTPA (Nemesis) id 0LrGCe-1gClxH0XQS-0133CS; Thu, 21 Jun 2018 18:48:27 +0200 Date: Thu, 21 Jun 2018 18:48:26 +0200 From: Polytropon To: Manish Jain Cc: FreeBSD Questions Subject: Re: Minimum size of freebsd-boot Message-Id: <20180621184826.9ae9ed8d.freebsd@edvax.de> In-Reply-To: <024a7da5-4d80-960c-9479-34fef887ff35@yandex.com> References: <024a7da5-4d80-960c-9479-34fef887ff35@yandex.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:K1:5WClVUKOcxEqxrBw8vJnwoluDEru7MAzPeeNGCtt7sP6S/5pgPi MgjkP9IU3QEWH6CaNorTJuWJxk8ZhSc7va8GXP+yIMncbtUw5SfRTuBo2dDdl3V6qk++AGa gHyR+LG+KgCICvbaUILR/6i6Sp7ClS2LE1f9W+sGc8l25A+tK2bka/URwls25NJpAyxVf1a JoKOwtD7S2+HRp2xE+XmA== X-UI-Out-Filterresults: notjunk:1;V01:K0:Ije2TK4Jhro=:NlwLGBsfQ4lWrVB2nh0yyt 0LixSryABhkDihF/9dltLl1HD/H/IDQxLJgBd67bwd2OeixaX7nKbyWQ32biFnVjaa1Eh3HQp rQDQVTmis14jPsaYu/TIP2iGcSPBZLsbaSnWKiTMPruE4lxgZR4S8OkKDTyI1ytfE1vaGIe7M qfNa9+AgjtAYjdSpq4LTFs3jvyFSzz/+V0xWQwgTS8GBIF4y33a3B6SP0/WmxCjXNP0YWfTd3 ChFJWutQg2Nyx94w9Bf4QOVosJotuKehI2xXvAObjQZLvoBGtws9Sty40Q845Z8Q6R7LPhMXk 2f/CSQIsPm3viWjTlQgmVqXsWLpsuTUCLjgntVZcvzUrLRW+87u154LVjIAXf7Oqg0iMZvI2M 7TgzY9cn3+fKcAu0h/Bas2kInJ7dNmj2UoQOUHb9PZL3aDQQMVGmeK4x62o7i5ZZuMe/BIiok aJXG2i7s0QcsWpI4wUWmyGB4Hrnw1N87z6R5MTafQn/yWs2zfTU+xePyqOwNF25gVYyjuUuKI wuNUsKvRA0/I6n9V7qb6sezgCii9dWkURUIij9VZEVsiRa6cl56H+Ern0QoiRVIpwh21Qc94a nNSomdcieH56fKqaJy60tOe/WKhqB0jI/6ekbJwcPwXxLK2kZSEgDk3ELSCj7AxFi9L6Pemn6 ECXC1EX492OuHYUPUVOon6aWeDmmHLyS1jOcKTVQJwcAHmuFvjm3yhEjxT1CunF3z6e0nicPm w68IjHG3yqeQ0QiX X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 21 Jun 2018 16:48:35 -0000 On Thu, 21 Jun 2018 21:45:38 +0530, Manish Jain wrote: > Under GPT, FreeBSD needs a freebsd-boot partition of max size 512 KB. Is > there a minimum size too ? The minimum size depends on what you require on the /boot partition. The ZFS loader is bigger than the classic UFS-only loader. Older FreeBSD documentation suggested a smaller size (approx. 40 kB) which today probably wouldn't be sufficient. Note that the whole partition is loaded into memory. And partition alignment is also important. That's why 512 kB is a good value (2^9). :-) Subsequent partitions typically start at the next multiple of 1 MB (which fits both 512 B and 4 kB sector size). So you could try to create a smaller /boot partition, but the next one, maybe / or swap, would start at 1 MB anyway. Also see: http://www.wonkity.com/~wblock/docs/html/disksetup.html https://www.freebsd.org/doc/handbook/bsdinstall-partitioning.html https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=211361 https://forums.freebsd.org/threads/freebsd-boot-size.64794/ -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ...