From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9B027C433F5 for ; Mon, 2 May 2022 16:38:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343626AbiEBQmM (ORCPT ); Mon, 2 May 2022 12:42:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1386334AbiEBQly (ORCPT ); Mon, 2 May 2022 12:41:54 -0400 X-Greylist: delayed 487 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Mon, 02 May 2022 09:38:21 PDT Received: from plutone.assyoma.it (unknown [212.237.56.195]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BDE20B1F6 for ; Mon, 2 May 2022 09:38:21 -0700 (PDT) Received: from webmail.assyoma.it (localhost [IPv6:::1]) by plutone.assyoma.it (Postfix) with ESMTPA id 052FE1026164 for ; Mon, 2 May 2022 18:30:11 +0200 (CEST) MIME-Version: 1.0 Date: Mon, 02 May 2022 18:30:10 +0200 From: Gionatan Danti To: netdev@vger.kernel.org Subject: Force mavtap interfaces up User-Agent: Roundcube Webmail/1.4.13 Message-ID: <116c870676ecab331ec3c76aaec7bf0f@assyoma.it> X-Sender: g.danti@assyoma.it Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Dear list, I would like to ask if, and how, it is possible to force a macvtap interface up even when the underlying physical device has no link (reporting NO-CARRIER). From my understanding, I can do that via something as "ip link set macvtap0 protodown off". And it works, indeed. However, if the underlying physical device is plugged & unplugged again, the macvtap0 interface goes down with it; to restore it, I need to re-run the above "protodown off" command. Does a method exists to always force one or more macvtap interfaces up, regardless the physical link status? Full disclosure: I am trying to use macvtap rather than plain bridge for a KVM host and I stumbled across the behavior described above. If the physical interface is disconnected, the guests lose connection with each other. With a classical bridge setup, disconnecting the physical interface only interrupt communication with outer guest/hosts (but internal traffic is preserved). Regards. -- Danti Gionatan Supporto Tecnico Assyoma S.r.l. - www.assyoma.it email: g.danti@assyoma.it - info@assyoma.it GPG public key ID: FF5F32A8