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 47A717DD56 for ; Tue, 9 Nov 2021 17:15:23 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 455931052A for ; Tue, 9 Nov 2021 17:15:23 +0100 (CET) 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) server-digest SHA256) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id 9FB671051B for ; Tue, 9 Nov 2021 17:15:19 +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 647D6427FE; Tue, 9 Nov 2021 17:15:19 +0100 (CET) Message-ID: <46238588-9bd7-94e8-bf54-abe9d782f625@proxmox.com> Date: Tue, 9 Nov 2021 17:15:17 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:95.0) Gecko/20100101 Thunderbird/95.0 Content-Language: en-US To: Proxmox VE development discussion , "DERUMIER, Alexandre" , "aderumier@odiso.com" References: <20211006083220.1145952-1-aderumier@odiso.com> From: Thomas Lamprecht In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL 1.677 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 KAM_SHORT 0.001 Use of a URL Shortener for very short URL NICE_REPLY_A -3.06 Looks like a legit reply (A) 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. [omnisecu.com, yhbt.net] Subject: Re: [pve-devel] [PATCH pve-cluster] sysctl: disable net.ipv4.igmp_link_local_mcast_reports 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, 09 Nov 2021 16:15:23 -0000 On 09.11.21 16:52, DERUMIER, Alexandre wrote: > This is really specific to local-link multicast, and it's should only > be use for some specific routing protocol > > https://yhbt.net/lore/all/1439396033-6264-1-git-send-email-pdowney@brocade.com/T/ > https://www.omnisecu.com/tcpip/ipv4-link-local-multicast-addresses.php > > So, I'll not break multicast services inside the vm. > > Maybe if hypervisor use ospf routing protocol, but anyway, we don't > have any infos about true vm ip/mac on fwbr bridges. hmm, ack thx for the info, so the sysctl can be fine. > actually corretly activate the fwbr bridge before plugging to vmbr, > > my $create_firewall_bridge_linux = sub { > ... > &$cond_create_bridge($fwbr); > &$activate_interface($fwbr); > copy_bridge_config($bridge, $fwbr); > veth_create($vethfw, $vethfwpeer, $bridge); > > &$bridge_add_interface($fwbr, $vethfw); > &$bridge_add_interface($bridge, $vethfwpeer, $tag, $trunks); > &$bridge_add_interface($fwbr, $iface); > }; > > but it seem that igmp is sent some millisecond later > > A simple sleep like, > > &$cond_create_bridge($fwbr); > &$activate_interface($fwbr); > sleep(1); > &$bridge_add_interface($fwbr, $vethfw); > > and the igmp report from fwbr is not going to vmbr. > (but, maybe this is more ugly than a sysctl knob) > yeah such sleeps are ugly and still racy, we could poll for the fwbr to be up? E.g., something like: my $round = 0; while (1) { last if PVE::Tools::file_read_firstline("/sys/class/net/$fwbr/operstate") =~ "up"; die "timeout on waiting for $fwbr to become ready\n" if ++$round > 100; usleep(10 * 1000); # 100 * 10ms = 1s } (did not test it) >> Should it be an FW option? > > It could be. > > but it need to be persistant at firewall service stop, as when we > shutdown the server, igmp report could be emit on vm/ct shutdown. > and at boot, it should be enabled before the vm auto-start > > Personnaly, I think it should be disabled by default, with an knob to > enable it. > , as a majority of basic users don't known what it is. (And advanced > users using routing protocol, should be aware of this option). ah yea, with default on I meant that the sysctl would be default on (so the local mcast reporting default off), sorry for the confusion. We wouldn't need a actual config knob either as an admin that depends on this can just configure a higher-priority sysctl.d file..