From owner-freebsd-questions@freebsd.org Fri Nov 22 17:49:31 2019 Return-Path: Delivered-To: freebsd-questions@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id BA4121BD009 for ; Fri, 22 Nov 2019 17:49:31 +0000 (UTC) (envelope-from kab00m@lich.phys.spbu.ru) Received: from skeleton.phys.spbu.ru (skeleton.phys.spbu.ru [195.19.241.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 47KP7t088Dz42c5 for ; Fri, 22 Nov 2019 17:49:28 +0000 (UTC) (envelope-from kab00m@lich.phys.spbu.ru) Received: from skeleton.phys.spbu.ru (localhost [127.0.0.1]) by skeleton.phys.spbu.ru (Postfix) with ESMTP id 665F8902E0 for ; Fri, 22 Nov 2019 20:49:19 +0300 (MSK) (envelope-from kab00m@lich.phys.spbu.ru) Received: from [10.4.4.236] (unknown [91.108.27.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by skeleton.phys.spbu.ru (Postfix) with ESMTPSA id 20114902C2 for ; Fri, 22 Nov 2019 20:49:19 +0300 (MSK) (envelope-from kab00m@lich.phys.spbu.ru) Subject: Re: DHCP server failover: advise is needed To: freebsd-questions@freebsd.org References: <53102df9-ca90-6338-7ff2-c370a42c690e@kicp.uchicago.edu> From: Dima Veselov Message-ID: <943ea22c-ce4d-e6d0-2ee6-21dea3af075d@lich.phys.spbu.ru> Date: Fri, 22 Nov 2019 20:49:18 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 MIME-Version: 1.0 In-Reply-To: <53102df9-ca90-6338-7ff2-c370a42c690e@kicp.uchicago.edu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Virus-Scanned: ClamAV using ClamSMTP X-Rspamd-Queue-Id: 47KP7t088Dz42c5 X-Spamd-Bar: + Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=none (mx1.freebsd.org: domain of kab00m@lich.phys.spbu.ru has no SPF policy when checking 195.19.241.202) smtp.mailfrom=kab00m@lich.phys.spbu.ru X-Spamd-Result: default: False [1.03 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; NEURAL_HAM_MEDIUM(-0.12)[-0.117,0]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-questions@freebsd.org]; TO_DN_NONE(0.00)[]; AUTH_NA(1.00)[]; RCPT_COUNT_ONE(0.00)[1]; RCVD_COUNT_THREE(0.00)[3]; RCVD_TLS_LAST(0.00)[]; NEURAL_SPAM_LONG(0.24)[0.244,0]; DMARC_NA(0.00)[spbu.ru]; R_SPF_NA(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:5495, ipnet:195.19.241.0/24, country:RU]; MID_RHS_MATCH_FROM(0.00)[]; IP_SCORE(0.00)[country: RU(0.01)] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 22 Nov 2019 17:49:31 -0000 On 22.11.2019 20:00, Valeri Galtsev wrote: I had been in same situation as you described, my advice may be handy. > Could someone point to description of working DHCP failover configuration? I used https://kb.isc.org/docs/aa-00502 as an instruction. > I do not want to make two independent DHCP servers handling half of the > pool each. We are not that rich as far as IP space is concerned. > I am not married to ISC DHCP server, so any one I can run on FreeBSD > will do, because: > > > My current configuration is something that was gradually migrated and/or > adjusted through several generations of systems, and server versions > over the years. It works. When I tried to incorporate what I need for > failover following ISC documentation, and some people's guides, I > discovered, I need more sophisticated structure of sections and > subsections, which I figured out finally. But the annoying part was: in > ISC documentation there is no general stricture of which section can > appear inside which; like: Basically, ISC DHCPD allow described structures and nothing more. Being on your side I had to do some work like moving static hosts in main config and reorganize subnets. This seemed noisy but appeared quite easy. For detailed advice we need to see your config or questionable parts of it. > So, I am not married to ISC DHCP server, we didn't get along now as far > as my use of documentation is concerned. Anything that works - with > failover! - on FreeBSD will be great. I can email you my own working configuration. General advice - try to make configuration as plain as it might be. If you have working subnets with working pools you just add failover peer and it start working. -- Dima Veselov Physics R&D Establishment of Saint-Petersburg University