From nobody Mon Jun 9 14:26:44 2025 X-Original-To: net@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4bGDlC532rz5yCjw for ; Mon, 09 Jun 2025 14:27:03 +0000 (UTC) (envelope-from pprocacci@gmail.com) Received: from mail-ej1-x632.google.com (mail-ej1-x632.google.com [IPv6:2a00:1450:4864:20::632]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "WR4" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4bGDlC30yKz464q; Mon, 09 Jun 2025 14:27:03 +0000 (UTC) (envelope-from pprocacci@gmail.com) Authentication-Results: mx1.freebsd.org; none Received: by mail-ej1-x632.google.com with SMTP id a640c23a62f3a-ade5ca8bc69so152624466b.0; Mon, 09 Jun 2025 07:27:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1749479216; x=1750084016; darn=freebsd.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=8TtuS2qvjNVOxD0PAs4QnFC+7UQX/d2xGki5ImIi2B0=; b=NPpM3Uly1KKUrjCp7CNIZlDrVi3VOOlwefTyhTvAgGA/Px4VQ0hv8X+pPy/UvPjOOu ZlsvgcQ88uPM6Bos90esT/fdMtcV8ygwcYfieAdxpT19lDLNN8d6Q+EzQqXkyerooZzO Y4PxvZLeCvRjDZPLHyS+dcMcERw27+Afe9xZ4hRfTqnBhhcsEBeILFPBUM0tQbxwSsh1 xgeNtZTBgnwXpeq4b1J+S8oOgngN1wZKOC09P5fumcn/QUKkM1WMgfS1JjntR2AZrqQn 9tCvM0xD+E0J4QCyEn7V60ShKA/wFyh5x9+fkria4N1vH5YVJVj3mF/kPcsYqjm3ZYx7 5sXw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1749479216; x=1750084016; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=8TtuS2qvjNVOxD0PAs4QnFC+7UQX/d2xGki5ImIi2B0=; b=OFSdb1h9U49Qb1a6G+qDprn0JHNpwJKy0Rovv0/KfdXnYZiNbBOGutroXgPGBsHwrg ZZCMrssA4PUp6gEzzfgZ6WHQVkxxm5I5o0mhTZXUss6XXDjjikoZT5G6xLaj+uBIDwVi TSvke9tT8kjSzuA1NNcV/WA6I1OCVgVb3IOLkcTqt6cilo5U1vpFvfKixBNKF/eDOE1B 7mT8/ux8aHdrQJSl9R4b0O+7wA7hS1DwzbW5NEm6Pe6ZXmEwGSLJX7d+TMdHhXAOA3of MMZuDbRgL8HD/ls7HYUfCkOMTWnvBp/IbvxaKHg7CtK9ai8onyQxPuhLlmKiNj5OvyaX /EOA== X-Gm-Message-State: AOJu0YxjLhXbF56JdQlPdirerp769YTQ7IySLTK1yhbz3u9hDIqlDNxs zr/Rv1YqlUgCpdImHxL1L0mdzxKr9kYbXzrwwf8WNL+iBiUKW0Tnn2I+aL1Nvk+HGdvxSw6ZiBr CfFAric7bG/uEfJbRk0edSMUsoDNZFg0KEME= X-Gm-Gg: ASbGncu+kEXE5jHUTezmJCN9yw/oocYucpMQxxTYWTxt9rzof1bbliivLAEAqZOnP4V F+mqBH6DsXGApg93Tw4rkKRBZLFexZHNzOebze4noVxx63K+/u0NPHvgbXQRuP3Vhb47AaneDh4 7qjckT9Ghy0U70xwfA5nh5BZJujbEQMS+Jo9Fulz8Q X-Google-Smtp-Source: AGHT+IFRzhQDjNVhICpYsSxpfLCHPjWzdLIa1oXP5v4wImYnsNRaQPdIslSYisPAirAOUiKKtLS7iKKD++R21NEh9dM= X-Received: by 2002:a17:907:3f94:b0:ad5:5b2e:655b with SMTP id a640c23a62f3a-ade1aa8b88cmr1207777966b.25.1749479216115; Mon, 09 Jun 2025 07:26:56 -0700 (PDT) List-Id: Networking and TCP/IP with FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-net List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-net@FreeBSD.org MIME-Version: 1.0 References: In-Reply-To: From: Paul Procacci Date: Mon, 9 Jun 2025 10:26:44 -0400 X-Gm-Features: AX0GCFtOxqSc6sSw1AETwhsuCXDtcE2Hk4cLm7K9jTo07EmZB-m0Ko8OTCPQqPo Message-ID: Subject: Re: dhclient vs aliases To: Andriy Gapon Cc: net@freebsd.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 4bGDlC30yKz464q X-Spamd-Bar: ---- X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:15169, ipnet:2a00:1450::/32, country:US] Re: https://forums.freebsd.org/threads/dhclient-trashing-alias-ip-address-u= pon-reconnect.58729/ You can use a dhclient.conf(5) entry like this to guarantee that the alias is re-applied every time the interface gets a new address from DHCP (or the old lease is re-applied): Code: alias { interface "em0"; fixed-address 10.0.0.3; option subnet-mask 255.255.255.0; } On Mon, Jun 9, 2025 at 10:20=E2=80=AFAM Andriy Gapon wrot= e: > > > Apologies if this is a FAQ and maybe it has always been like that but I'v= e just > noticed this. > > A switch needed to be rebooted, so on a FreeBSD host a link went down and= then > up on an interface connected to the switch. > Apparently triggered by those events, dhclient decided to renew the inter= face's > IP address. Afterwards, all alias IP addresses on that interface were cle= ared. > Just in case, the new IP address was exactly the same as the old IP addre= ss > (it's "hardwired" in the DHCP server configuration). > > This was unhelpful because the host runs a number of jails with a simple = IP > configuration via aliases. > > -- > Andriy Gapon > > --=20 __________________ :(){ :|:& };: