From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: 3-way mirror to RAID-6 Date: Tue, 26 Dec 2017 08:53:27 +1100 Message-ID: <87incu79uw.fsf@notabene.neil.brown.name> References: Mime-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Gandalf Corvotempesta , Linux RAID Mailing List List-Id: linux-raid.ids --=-=-= Content-Type: text/plain On Mon, Dec 25 2017, Gandalf Corvotempesta wrote: > Hi to all > I have a server with a 3way mirror. > As I have to increase the total available space, one solution would be to > replace all disks with bigger ones, but this is expensive. > > Another solution would be to add just one disk and then reshape from > RAID-1 to RAID-6 > > Do you have any guide on how to do this reshape on a running array ? > Thank you. I suggest you add the new device with "mdadm --add", then try the reshape with "mdadm --grow /dev/mdXXX --level=6 --raid-devices-4". It might not work quite that easily - I think you need to first convert the raid1 to a 2-way mirror, but that is easy enough mdadm --grow /dev/mdxxx --raid-devices=2 NeilBrown --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEG8Yp69OQ2HB7X0l6Oeye3VZigbkFAlpBc1cACgkQOeye3VZi gbly1w//WvNWJ3sKpEoF1AasY1kjbB6KmL1h8KlJp+jCY10D1NRfAdtgBVkhG/9t JuMuEC6I7fzLjMG/1Lk22dEc5+mN4tefXYhVu08cQD1nlpYQngrfp2H/7mWU/co8 YKpOTUvuwJddvSBO45vYmyC26bXbIF7F3lC6E0jiMijLaOappLeS6+oTAsAWdOso 7ElVKsy/Aq4Y+DIPOqGFp2z13xqvF7KSpCs/Yfn63Q36OaAXST03AFxyFawrLACt 0Wrk+1xigwEmOTBL+9q5DKcg3ly4sMY1BggG02y8MPrtuhUGDpO6SCMBlRcjAmEN BwjBJg/eyweFw2C/Smxs0N+q+KSk8XR+LjJPrZDdn6pt6odJP9sKZ9MJrtL9Mtkf /IUzphOXaPTX3bmLC7XJlhpCGv7BvFLsezdrjbNI0mtHonqTAUA6QdjslpqPCfCC 2cLS9uNfDz8F3puxk/tB4OtltwmBglxR3wwm3GoNYkr76VV1EMqwRc1lYQWHxao7 dlppqYh6JWPJ4AD2eWrSb27Bm9jJN7Voxhdntjg3ON2O5DCB+03yEerXEqar9w6L itV2Iuptu8aWVgymSIxSVWZmXn0Bw0UAY88y4n5CuJRnJS2K/uW83EMyAO+VuUYR /qUUW5bkyARnj4AruWovgw4BxB/bXZeGSn7gsLywpydo5TVP2Aw= =gD5G -----END PGP SIGNATURE----- --=-=-=--