From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: [BUG] Xen Remus, DRBD Protocol D and old Linux kernels Date: Wed, 3 Feb 2016 11:27:09 -0500 Message-ID: <20160203162709.GA22750@char.us.oracle.com> References: <1453109378.6020.100.camel@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: <1453109378.6020.100.camel@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: Shriram Rajagopalan , Yang Hongyang , Wen Congyang , Pato =?iso-8859-1?Q?S=E1inz?= , xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On Mon, Jan 18, 2016 at 09:29:38AM +0000, Ian Campbell wrote: > Just adding the Remus maintainers to the CC. ping? > = > On Fri, 2016-01-15 at 15:26 -0300, Pato S=E1inz wrote: > > Good evening, people. > > = > > More than a bug, it's an issue, a big one IMO. > > = > > Even though information on the Remus project and its implementation is = kind of > > scarce on the internet and is usually outdated (the project could use s= ome love > > on that side of things, though it seems that on the coding side, it's > > still being > > properly maintained), there's a huge problem in the current implementat= ion: its > > storage depends on a custom patch developed for a very old version of D= RBD. > > = > > Currently, the wiki points that in order to use Remus you must use it > > with a custom > > version of DRBD, forked from 8.3.11 (and there's also a patch for > > 8.3.9). Support > > for these versions have been dropped for almost 3 years, and they are o= nly > > compatible with Linux kernels 3.0-3.4: most distros have already droppe= d these > > kernels and deleted them from their repositories: even kernel.org plans= to drop > > support for the 3.4 kernel in September this year. Building your own is= an > > unnecessary hassle. > > = > > These problems make Remus practically unusable, despite being one of the > > coolest features Xen has in my honest opinion. > > = > > This issue has also been brought up at least once on the DRBD mailing l= ist[1] > > and until there's more cooperation between the Xen project and LINBIT to > > develop a more robust Protocol D, they've refused to pull the patch int= o their > > tree to be maintained. > > = > > It's worth noting that the "official" patch (by rshiriam) is somewhat > > simple[2][3]. > > = > > A solution to this for the short term would be to port the patch to the= current > > DRBD version (8.4.7-1) and in the long term, to collaborate with LINBIT= so > > the Xen project doesn't have to maintain their own downstream changes, = and > > we benefit from LINBIT's experience on realiable storage. > > = > > The short term solution seems like a very quick one, since the original= patch > > is small-ish, and I've been trying to do it[4] but simply C isn't my st= rong suit > > and I don't know much of DRBD's source, even after doing a cursory read= ing > > of it. > > = > > I know this is an open source project and thus most developers are > > volunteers, but > > this kind of issue really is a show-stopper that keeps me (and presumab= ly many > > other people) from using the awesome feature that Remus is. > > = > > [1]: http://lists.linbit.com/pipermail/drbd-user/2013-October/020370.ht= ml > > [2]: http://remusha.wdfiles.com/local--files/configuring-and-installing= -remus/drbd-8.3.9-remus.patch > > [3]: https://github.com/macrosheep/remus-drbd/commit/2685b294f5b416d827= bdf446a69c88ab04df50dd > > [4]: https://github.com/superpatosainz/remus-drbd > > = > = > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel