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 0CAFB734CD for ; Fri, 18 Jun 2021 08:50:02 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id E9E5E234FA for ; Fri, 18 Jun 2021 08:50:01 +0200 (CEST) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (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 209A1234EF for ; Fri, 18 Jun 2021 08:50:00 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id E884A441FD for ; Fri, 18 Jun 2021 08:44:14 +0200 (CEST) Date: Fri, 18 Jun 2021 08:44:08 +0200 From: Fabian =?iso-8859-1?q?Gr=FCnbichler?= To: Proxmox VE user list References: <1375274439.1944470.1623941231996.ref@mail.yahoo.com> <1375274439.1944470.1623941231996@mail.yahoo.com> In-Reply-To: <1375274439.1944470.1623941231996@mail.yahoo.com> MIME-Version: 1.0 User-Agent: astroid/0.15.0 (https://github.com/astroidmail/astroid) Message-Id: <1623998195.h71kiadsrn.astroid@nora.none> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-SPAM-LEVEL: Spam detection results: 0 AWL 0.785 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment 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. [proxmox.com] Subject: Re: [PVE-User] memory management of a vm in HA X-BeenThere: pve-user@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE user list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 18 Jun 2021 06:50:02 -0000 On June 17, 2021 4:47 pm, marcos negrini wrote: > Hello:I am administrator of a proxmox cluster and I have been testing Hig= h Availability, and I am very satisfied with the performance; but I wanted = to understand a little more in depth how the memory management works. I did= the tests in a cluster of 3 servers with a SAN storage, I tried to cut the= power to a physical server and almost instantly the vm's that were configu= red with HA went to the next node, my question is, how do you manage the me= mory of each vm's? do you pre-share it in the other physical servers so tha= t the memory status of each one is not lost? how do you manage the loss of = the information that was not copied? is there any technical document of thi= s implementation in proxmox?Regardspd: sorry for my english level, I hope m= y doubt is interpreted. I'd suggest reading [1] as a starting point. To answer your questions: - guest memory is not replicated or shared between nodes, HA just tries=20 to ensure the guest is running "somewhere" according to the HA=20 configuration - ideally your guests' volumes are on shared storage, but if you can=20 live with losing data since the last replication, ZFS with replication=20 can also be an option - if a node disappears/crashes/loses quorum/.. it gets fenced, the still=20 quorate part of the cluster will notice and "steal" the affected HA=20 resources -- if the fenced node is still responsive, it's watchdog timer will=20 expire and it will shutdown (stopping all running guests in the process) -- the stealing node will wait a certain amount of time to give the=20 fenced node time to be completely fenced, then it will take over the=20 guest configs and start the guest - additionally, you can configure what should happen to HA resources on=20 (orderly) node shutdown/reboot (see "Node Maintenance" in the admin=20 guide) - here one of the options is to migrate them to other nodes,=20 which is possibly what you triggered in your test? 1: https://pve.proxmox.com/pve-docs/pve-admin-guide.html#chapter_ha_manager= =20