From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) by lore.proxmox.com (Postfix) with ESMTPS id E41B31FF13E for ; Fri, 20 Feb 2026 14:26:42 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id A8D7F8A49; Fri, 20 Feb 2026 14:27:33 +0100 (CET) From: Maximiliano Sandoval To: Manuel Federanko Subject: Re: [PATCH docs] qdevice: correct qdevice partition tie breaking section. In-Reply-To: <20260220125709.59612-1-m.federanko@proxmox.com> (Manuel Federanko's message of "Fri, 20 Feb 2026 13:57:09 +0100") References: <20260220125709.59612-1-m.federanko@proxmox.com> User-Agent: mu4e 1.12.9; emacs 30.1 Date: Fri, 20 Feb 2026 14:27:28 +0100 Message-ID: MIME-Version: 1.0 Content-Type: text/plain X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1771594038530 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.085 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment RCVD_IN_VALIDITY_CERTIFIED_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_RPBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_SAFE_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Message-ID-Hash: TESFIWWOAVEKSPIYNHPAV3B7MLEJRVYN X-Message-ID-Hash: TESFIWWOAVEKSPIYNHPAV3B7MLEJRVYN X-MailFrom: m.sandoval@proxmox.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; loop; banned-address; emergency; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: pve-devel@lists.proxmox.com X-Mailman-Version: 3.3.10 Precedence: list List-Id: Proxmox VE development discussion List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Manuel Federanko writes: > The partition that gets a vote is not randomly chosen, but depends on > the configuration of the qdevice in corosync.conf. > > A partner asked about predictable behavior for vote casting by the > QDevice. The documentation of corosync and ours didn't align. > > Setting tie_breaker influences how a partition is chosen for votes, > which was tested with a 2-node test-cluster. > > Signed-off-by: Manuel Federanko > --- > pvecm.adoc | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/pvecm.adoc b/pvecm.adoc > index 0ed1bd2..899a4de 100644 > --- a/pvecm.adoc > +++ b/pvecm.adoc > @@ -1266,8 +1266,10 @@ Tie Breaking > ^^^^^^^^^^^^ > > In case of a tie, where two same-sized cluster partitions cannot see each other > -but can see the QDevice, the QDevice chooses one of those partitions randomly > -and provides a vote to it. > +but can see the QDevice, the QDevice chooses the partition which has > +the lowest node id and provides a vote to it. This behavior can be tuned with > +the configuration option `tie_breaker` (see `man corosync-qdevice` for more > +information) and requires a restart of `corosync-qdevice.service` on all nodes. > > Possible Negative Implications > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ I would personally only mention the man page so to avoid running out of sync, but this looks good to me as-is. Reviewed-by: Maximiliano Sandoval -- Maximiliano