From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adam Goryachev Subject: Re: Howto avoid full re-sync Date: Wed, 12 Sep 2012 22:52:18 +1000 Message-ID: <50508582.3070501@websitemanagers.com.au> References: <50497AE6.2010005@websitemanagers.com.au> <81BAA7A8-B1C3-49A1-A600-A9D9D8279E30@bj-ig.de> <504D223A.6020707@websitemanagers.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: =?ISO-8859-1?Q?Ralf_M=FCller?= Cc: Linux RAID List-Id: linux-raid.ids On 11/09/12 00:12, Ralf M=FCller wrote: > Besides all the stuff about fix your server, a raid is not a backup a= nd you risk your data - simply add a write intent bitmap: > > mdadm /dev/md2 --grow --bitmap=3Dinternal I've added this across a number of my systems now, and it seems to work really well (Thank You), especially one system which has a RAID1 with a= n external USB drive + internal drive which normally take over 2 days for a full resync. Can you suggest if there is any dis-advantage to using the bitmap (mayb= e write performance will suffer), or disk space is reduced, or .... While I can see the benefits, I'm just wondering if it might be too goo= d to be true, or what I am missing.... Thanks again for your assistance. Regards, Adam --=20 Adam Goryachev Website Managers Ph: +61 2 8304 0000 adam@websitemanagers.com= =2Eau =46ax: +61 2 8304 0001 www.websitemanagers.c= om.au -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html