From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id D664862B03 for ; Tue, 27 Oct 2020 18:12:29 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id CAFBC195DD for ; Tue, 27 Oct 2020 18:12:29 +0100 (CET) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [212.186.127.180]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id 4829B195D1 for ; Tue, 27 Oct 2020 18:12:28 +0100 (CET) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 0E08745F5F for ; Tue, 27 Oct 2020 18:12:28 +0100 (CET) From: Alwin Antreich To: pve-devel@lists.proxmox.com Date: Tue, 27 Oct 2020 18:12:23 +0100 Message-Id: <20201027171223.3400827-1-a.antreich@proxmox.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SPAM-LEVEL: Spam detection results: 0 AWL -0.239 Adjusted score from AWL reputation of From: address KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment KAM_NUMSUBJECT 0.5 Subject ends in numbers excluding current years KAM_SHORT 0.001 Use of a URL Shortener for very short URL RCVD_IN_DNSWL_MED -2.3 Sender listed at https://www.dnswl.org/, medium trust SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [ceph.com] Subject: [pve-devel] [PATCH docs] ceph: add warning for min_size 1 X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 27 Oct 2020 17:12:29 -0000 Signed-off-by: Alwin Antreich --- pveceph.adoc | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/pveceph.adoc b/pveceph.adoc index 84a45d5..39da354 100644 --- a/pveceph.adoc +++ b/pveceph.adoc @@ -462,6 +462,10 @@ state. NOTE: The default number of PGs works for 2-5 disks. Ceph throws a 'HEALTH_WARNING' if you have too few or too many PGs in your cluster. +WARNING: **Do not set a min_size of 1**. A replicated pool with min_size of 1 +allows I/O on an object when it has only 1 replica which could lead to data +loss, incomplete PGs or unfound objects. + It is advised to calculate the PG number depending on your setup, you can find the formula and the PG calculator footnote:[PG calculator https://ceph.com/pgcalc/] online. From Ceph Nautilus onwards it is possible to -- 2.27.0