From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50664) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eKPir-0001NF-86 for qemu-devel@nongnu.org; Thu, 30 Nov 2017 09:21:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eKPiq-0000IZ-9a for qemu-devel@nongnu.org; Thu, 30 Nov 2017 09:21:53 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57308) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eKPiq-0000Hb-2p for qemu-devel@nongnu.org; Thu, 30 Nov 2017 09:21:52 -0500 References: <3c1d9325-56a9-225d-4ff8-230f8ed52fed@virtuozzo.com> From: Max Reitz Message-ID: <76f5ec24-112f-455a-4ad4-5c97d7182f36@redhat.com> Date: Thu, 30 Nov 2017 15:21:47 +0100 MIME-Version: 1.0 In-Reply-To: <3c1d9325-56a9-225d-4ff8-230f8ed52fed@virtuozzo.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="QDtfAc2h404MN5TnKwfAG8Wn0vU8C7Gfm" Subject: Re: [Qemu-devel] export root node for write through NBD List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Vladimir Sementsov-Ogievskiy , qemu-devel Cc: Kevin Wolf , Eric Blake , Paolo Bonzini , "Denis V. Lunev" , Nikolay Shirokovskiy This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --QDtfAc2h404MN5TnKwfAG8Wn0vU8C7Gfm From: Max Reitz To: Vladimir Sementsov-Ogievskiy , qemu-devel Cc: Kevin Wolf , Eric Blake , Paolo Bonzini , "Denis V. Lunev" , Nikolay Shirokovskiy Message-ID: <76f5ec24-112f-455a-4ad4-5c97d7182f36@redhat.com> Subject: Re: export root node for write through NBD References: <3c1d9325-56a9-225d-4ff8-230f8ed52fed@virtuozzo.com> In-Reply-To: <3c1d9325-56a9-225d-4ff8-230f8ed52fed@virtuozzo.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 2017-11-30 08:47, Vladimir Sementsov-Ogievskiy wrote: > Hi all. >=20 > We need the following option: start vm in stopped mode (-S) and write > it's disk before start through NBD. > It should be absolutely safe, but unfortunately it is disallowed by roo= t > role of the disk. > Is there any workaround or if not, what is a true way to implement this= > possibility? >=20 > ---- > error message: > =C2=A0=C2=A0=C2=A0 unable to execute QEMU command 'nbd-server-add': Con= flicts with use > by drive0 as 'root', which does not allow 'write' on #block100 >=20 > --=20 One thing that comes to mind is adding the guest device only after you are done with NBD. The other of course is to set share-rw=3Don for the device. Max --QDtfAc2h404MN5TnKwfAG8Wn0vU8C7Gfm Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQFGBAEBCAAwFiEEkb62CjDbPohX0Rgp9AfbAGHVz0AFAlogE/sSHG1yZWl0ekBy ZWRoYXQuY29tAAoJEPQH2wBh1c9A+ucH/0JsWtV10o6TO+GqlblrgKT2S1/mleN3 NFST90nC+yxMSyi4/Rwq4nebF5YBd30rOnBGdASL9VyIK2vDsv47ndzGjaBSj/BT 1Oxyi27Gb/3rc6qV1kb8bp33gsZvGT9A5FbellCnmNvjXR15Xiozbf+F0keoF9zr nxtx267NfeDkwLOpK0chAg1BtSQ5DxbbQmNpLJTAS0Ga7UK/2Ln8X/0ZFSEfXwWV TZKBzYJvunfscAJXFMHfZcoFYCCjhMJYa8kfhp93Z6l0Lgs2ZOIcqpoLEQCNvxzM Kwa37PhDJwhFHLuXH9AEof4jss8woHdQoGtkYxr9YQ+ZnwiWmqDJ8+I= =zoM+ -----END PGP SIGNATURE----- --QDtfAc2h404MN5TnKwfAG8Wn0vU8C7Gfm--