From owner-freebsd-questions@freebsd.org Sun Oct 8 23:58:20 2017 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id C4A37E43291 for ; Sun, 8 Oct 2017 23:58:20 +0000 (UTC) (envelope-from luzar722@gmail.com) Received: from mail-it0-x236.google.com (mail-it0-x236.google.com [IPv6:2607:f8b0:4001:c0b::236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 06D066FFE2 for ; Sun, 8 Oct 2017 23:58:19 +0000 (UTC) (envelope-from luzar722@gmail.com) Received: by mail-it0-x236.google.com with SMTP id j140so6539704itj.1 for ; Sun, 08 Oct 2017 16:58:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-transfer-encoding; bh=p+V4j1/sGyFGk40qIKxP4yBSO68n0u+ohd72q3SocIU=; b=Okrq84Wk5CZBiyi+SrTHPaj0yFoBRqXG5F14W+4VkrsFyP9VTRJtSI90443/rs1tcy OcCuTeDgVVnpilaaQ9V4GwOwtqI73bzKT6+W5X1VdiOxEFgLhB36k/hHgRf4bHEnk2o6 rozMBuEx1S6KcfiPd0x8cE+zSKDboI2PV2/89vsum1Uo0fIRBQU/7rM6m73nfE/g0l+y g51UeVhLiIa2ruj+UdjsGiKHi9KV6ycY6OFPDeV52IY094SqH0Bt1v3/aM+VAG/tbEj9 UDWYq4gWNi9ngKhVjCRjbX37kAxxUB4fYCzx20hig82W/Buk+D4w6TsDnz1R8yY0q2UQ Ofsg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:date:from:user-agent:mime-version:to :cc:subject:references:in-reply-to:content-transfer-encoding; bh=p+V4j1/sGyFGk40qIKxP4yBSO68n0u+ohd72q3SocIU=; b=SAIysRP2uCFRRpi1KoYlOo0Kw5mDgPtuap0PdTnEQgteSrwTJt7gfPxwEYbEg147tO bcWWdseVlSFpPUwc1dXnL9N0DJFzojWo7o80woHS/K1Rx4VZGRa+e6qKsHYrV0J0Vgvj oF+VT7L8Fd8F2nJ4xIQt90wo34PGcChQJTEk9HxpE2csVXYahkQ31r0VS/Ucn6W6dmBe 2eDBTOowqZTFjS8HVaqEcjgL7kQzZrgvdfWJwYaC3An35PX2FmYFqWa6PNOkN/WyUdNk GpFtcSJ6QJcrdGWHzHtCIhcPZUpNrFGdSic0WTwMOLLPQpAsbT8F92DzXFHMHBheECdz mpdg== X-Gm-Message-State: AMCzsaVK2t3s2A0tc4drUa5OH2I8/ACpbfhQJ1FicOExVJKXEJHks3vp j1Sf3tq3wJMXZyJyqdc2oDzOQPkG X-Google-Smtp-Source: AOwi7QB1ALd0JpCIrxj9Bt88c/l7e0ys/L9Pliq9OCXln0nHLxH8Vre3uLWWWpjRkKNFEAzhrD5BiA== X-Received: by 10.36.155.130 with SMTP id o124mr12092877itd.69.1507507099112; Sun, 08 Oct 2017 16:58:19 -0700 (PDT) Received: from [10.0.10.3] (cpe-65-25-55-192.neo.res.rr.com. [65.25.55.192]) by smtp.googlemail.com with ESMTPSA id g81sm2178088ioe.50.2017.10.08.16.58.18 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sun, 08 Oct 2017 16:58:18 -0700 (PDT) Message-ID: <59DABB98.6040009@gmail.com> Date: Sun, 08 Oct 2017 19:58:16 -0400 From: Ernie Luzar User-Agent: Thunderbird 2.0.0.24 (Windows/20100228) MIME-Version: 1.0 To: Mike CC: freebsd-questions@freebsd.org Subject: Re: forcing new dynamic ip address References: <59DA19E8.5000602@gmail.com> <259de481-2286-589f-ae18-8922d473813e@mgm51.com> In-Reply-To: <259de481-2286-589f-ae18-8922d473813e@mgm51.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 08 Oct 2017 23:58:20 -0000 Mike wrote: > On 10/8/2017 8:28 AM, Ernie Luzar wrote: >> Hello List; >> >> I have a "home service" account from my ISP. The ISP issues an dynamic >> ip address which has not changed in 12 years. >> >> My host has 2 NICs, one which is not used. I know if I plug the internet >> cable into the un-used NIC and make the appropriate config changes and >> reboot I will get a different dynamic ip address. >> >> Is there a simpler way to expire the lease to force the ISP dhcp to >> refresh with a different dynamic ip address? >> >> The goal is to have a cron job that gets a different dynamic ip address >> assigned to my host's front door every a week. >> >> Just another level of security to make it very hard for the script >> kiddies from finding any open ports I may have. >> >> Thanks for the help. > > > I have a few old NICs that i keep, not because I need to use them, but > because i want to be able to use their MAC address. > > Then I use one of the MAC addresses in rc.conf, e.g., > > ifconfig_em0="DHCP lladdr yo:ur:MA:C:ad:dr:es" > > My ISP assigns a new IP address when the DHCP server sees a new MAC address. > > Thank you. This is the solution I was looking for. I tested it and it works. But I have to first cycle the cable modem's power off/on to signal the isp network that new hardware is being used and prepare to do dhcp function.