Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On 6/27/2014 6:00 AM, drbd-user-request at lists.linbit.com wrote: > Send drbd-user mailing list submissions to > drbd-user at lists.linbit.com > > To subscribe or unsubscribe via the World Wide Web, visit > http://lists.linbit.com/mailman/listinfo/drbd-user > or, via email, send a message with subject or body 'help' to > drbd-user-request at lists.linbit.com > > You can reach the person managing the list at > drbd-user-owner at lists.linbit.com > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of drbd-user digest..." > > > Today's Topics: > > 1. Re: drbd-user Digest, Vol 119, Issue 22 (rf at q-leap.de) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Fri, 27 Jun 2014 11:12:50 +0200 > From: rf at q-leap.de > Subject: Re: [DRBD-user] drbd-user Digest, Vol 119, Issue 22 > To: Allen Chen <achen at harbourfrontcentre.com> > Cc: drbd-user at lists.linbit.com > Message-ID: <21421.13714.943726.997057 at gargle.gargle.HOWL> > Content-Type: text/plain; charset=us-ascii > >>>>>> "Allen" == Allen Chen <achen at harbourfrontcentre.com> writes: > Allen> Here is my explanation to use DRBD instead of md raid1: for > Allen> md raid1, if one member is physically removed from the > Allen> machine, and after you reconnect the same disk to md raid1, > Allen> MD will re-sync everything to it. > > Wrong, see below. > > Allen> It takes much more time. for DRBD, if the second disk is > Allen> removed from the machine, and after you reconnect the same > Allen> disk to DRBD, DRBD will sync whatever has been changed. It > Allen> take less time than MD raid1. > > md raid1 can do the same thing and is definitely the better tool for this > job. See e.g. > > https://raid.wiki.kernel.org/index.php/Write-intent_bitmap > > Roland > > ------- > http://www.q-leap.com / http://qlustar.com > --- HPC / Storage / Cloud Linux Cluster OS --- > > I found an interesting feature from DRBD when I test DRBD compered with MD raid1. I am seeking a "relax" disk backup solution. Of cause, both DRBD and raid1 can do it. But I need this feature: if the second node(DRBD) or disk(raid1) is offline(no disk errors, no nothing,just disconnected), and comes back later, I need the two nodes(DRBD) or disk(raid1) to be synced as soon as possible. In this case, DRBD takes a few seconds to sync whatever changed, and raid1 takes hours to sync the whole disk(also needs annually add the out of sync disk). So I want to use DRBD to replace raid1 in this case. Does it have any issue to run DRBD on the same machine? Allen