From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: Date: Thu, 27 Nov 2014 07:49:49 +1100 Message-ID: <20141127074949.7d437769@notabene.brown> References: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/bqvKv3M+BQi4tAY37SiAFWo"; protocol="application/pgp-signature" Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Travis Williams Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids --Sig_/bqvKv3M+BQi4tAY37SiAFWo Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Wed, 26 Nov 2014 12:38:44 -0600 Travis Williams wrote: > Hello all, >=20 > I feel as though I must be missing something that I have had no luck > finding all morning. >=20 > When setting up arrays with spares in a spare-group, I'm having no > luck finding a way to get that information from mdadm or mdstat. This > becomes an issue when trying to write out configs and the like, or > simply trying to get a feel for how arrays are setup on a system. >=20 > Many tutorials/documentation/etc etc list using `mdadm --scan --detail > >> /etc/mdadm/mdadm.conf` as a way to write out the running config for > initialization at reboot. There is never any of the spare-group > information listed in that output. Is there another way to see what > spare-group is included in a currently running array? >=20 > It also isn't listed in `mdadm --scan`, or by `cat /proc/mdstat` >=20 > I've primarily noticed this with Debian 7, with mdadm v3.2.5 - 18th > May 2012. kernel 3.2.0-4. >=20 > When I modify the mdadm.conf myself and add the 'spare-group' setting > myself, the arrays work as expected, but I haven't been able to find a > way to KNOW that they are currently running that way without failing > drives out to see. This nearly burned me after a restart in one > instance that I caught out of dumb luck before anything of value was > lost. >=20 mdadm.conf is the primary location for spare-group information. When "mdadm --monitor" is run, it reads that file and uses that information. If you change the spare-group information in mdadm.conf, it would make sense to restart "mdadm --monitor" so that it uses the updated information. mdadm --scan --detail >> /etc/mdadm.conf was only even meant to be a starting point - a guide. You are still responsible for your mdadm.conf file. NeilBrown --Sig_/bqvKv3M+BQi4tAY37SiAFWo Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIVAwUBVHY87Tnsnt1WYoG5AQLq/g//W4DumjMQZTpJXhMS2RXsniR/W+hhHX7k DB2M3O+UtgBmYcauy4ohMuwn9OZmb1pgrv9aa0kpVHVSu7tLN1c1fAzQuJiYOYjg QmVfDKcJHQUllra58t2VlmAA+9ZeruxXjeVE6yJTfn0JiApYJ3mWHPZ+H1jU5Cen 6o8xfgO/dhnhZitcmFLHUMXcVx3d9pLbzvF2phV4arwRvVhu+PYI0BKI1SNTWMB5 dUGYWYvGXzKzV4II5HJaU5o5DrS4kwJRDwMWgIAOGKb6IlwNuW6RIyXfhFc8N9fb h67kWnT/i6jkZoQTqKqiW8fCsvRfT6A/KtMiwvW4b1GX71TsiPG3ri4DpwHEewv+ nYpq2+upxlWTPmpHw5Nr2nLnOvcwuGhKvzsy18O8TPOuBJNlTICC7wRZYOi7V/40 L2HG1wWs15lsoCBvsKS1ZJAjBAkzVk0zpjctvUri0rChluxeUa9GEAv2FHl5SeHa C4GTb0trA8dbV1qf0/72gDYomh54kbq0WHcooy9c49gNwLdfInT9xTiB6/jx2Dgq Hbo7kJQQoD1dBIvM7FK6DhoDLb2YgZlgvUJ4wpZpWE4fDyNeUJy4bVJcRbmSbdXy 5URMln/0+KNg3UfF295upQH7K+Y6ZVbZHEbQNW2MCH3E1Dy9KJClwb/DmkZJM14+ nUVrw7bujQk= =wxQf -----END PGP SIGNATURE----- --Sig_/bqvKv3M+BQi4tAY37SiAFWo--