From owner-freebsd-fs@freebsd.org Tue Apr 24 06:14:37 2018 Return-Path: Delivered-To: freebsd-fs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id DC059FBCF79 for ; Tue, 24 Apr 2018 06:14:36 +0000 (UTC) (envelope-from karli@inparadise.se) Received: from mail.inparadise.se (h-112-105.A444.priv.bahnhof.se [158.174.112.105]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4832E800D3 for ; Tue, 24 Apr 2018 06:14:35 +0000 (UTC) (envelope-from karli@inparadise.se) Received: from localhost (localhost [127.0.0.1]) by mail.inparadise.se (Postfix) with ESMTP id 8921B431FC; Tue, 24 Apr 2018 08:14:34 +0200 (CEST) Received: from mail.inparadise.se ([127.0.0.1]) by localhost (mail.inparadise.se [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id VqJOTCZlWsjT; Tue, 24 Apr 2018 08:14:33 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by mail.inparadise.se (Postfix) with ESMTP id 54FB2431F2; Tue, 24 Apr 2018 08:14:33 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.inparadise.se 54FB2431F2 X-Virus-Scanned: amavisd-new at inparadise.se Received: from mail.inparadise.se ([127.0.0.1]) by localhost (mail.inparadise.se [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id vbgYk-2Z_rdd; Tue, 24 Apr 2018 08:14:33 +0200 (CEST) Received: from emp181-188.eduroam.uu.se (emp181-188.eduroam.uu.se [130.238.181.188]) by mail.inparadise.se (Postfix) with ESMTPSA id 31D5B431E9; Tue, 24 Apr 2018 08:14:33 +0200 (CEST) Message-ID: <1524550472.1130.10.camel@inparadise.se> Subject: Re: pNFS server completed From: Karli =?ISO-8859-1?Q?Sj=F6berg?= Reply-To: karli@inparadise.se To: Rick Macklem , "freebsd-fs@freebsd.org" Date: Tue, 24 Apr 2018 08:14:32 +0200 In-Reply-To: References: ,<1524471526.9560.51.camel@inparadise.se> Organization: InParadise Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.18.5.2-0ubuntu3.2 Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 24 Apr 2018 06:14:37 -0000 On Mon, 2018-04-23 at 21:00 +0000, Rick Macklem wrote: > Karli Sj=C3=B6berg wrote: > >=20 > > On Sun, 2018-04-22 at 21:18 +0000, Rick Macklem wrote: > > >=20 > > > Hi, > > >=20 > > > I have now updated the projects/pnfs-planb-server subtree of svn > > > with > > > what > > > I believe is a complete pNFS server. It now handles mirrored Data > > > Servers (DSs) > > > and recovery of a failed mirrored DS while the service is > > > operational. > > > It handle non-pNFS clients (such as NFSv3 mounts) via having the > > > MetaData > > > Server act as a proxy for Read/Write operations. > > > For pNFS capable NFSv4.1 clients, the Read/Write operations are > > > done > > > directly > > > on the appropriate DS(s), avoiding the MetaData Server (which act > > > like a normal > > > NFS server except for pNFS capable clients). > > >=20 > > > If you are interested in more information or doing testing, see: > > > http://people.freebsd.org/~rmacklem/pnfs-planb-setup.txt > > >=20 > > > I hope that this should be ready for head/current with some > > > additional testing. > > > I will post here asking the "collective" about this when I think > > > it > > > is ready. > > >=20 > > > If there are any volunteers on the doc side=C2=A0=C2=A0who would li= ke to > > > turn > > > the above > > > text file into a useful document, that would be greatly > > > appreciated. > > >=20 > > > Good luck with it, if you test it, rick > > Hi Rick! > >=20 > > I think this sounds amazing to have a distributed file server > > natively > > in FreeBSD, awesome! > >=20 > > One question that comes to mind is about the MDS: wouldn=C2=B4t that = be > > a > > SPOF?=C2=A0 > Yes, the MDS is just like a regular NFS server on FreeBSD. It is a > single point > of failure. >=20 > >=20 > > Maybe that has already been discussed and explained and I=C2=B4ve jus= t > > missed it, but would be nice to know. And if it is a SPOF, are > > there > > any plans of also mirroring MDS's as well? Perhaps a DS can be MDS > > to, > > something like that? > No plans w.r.t. mirroring the MDS. The pNFS client using Flexible > File Layout > knows to write to both mirrors (and the MDS can do so acting as a > proxy > for a client). >=20 > However, NFS clients don't know how to do NFS operations on multiple > NFS servers. As such, any mirroring would have to be implemented > "behind the > curtain" and I'll admit I don't know how to do that. >=20 > I did try using a clustered file system (GlusterFS) as a backend when > I first > implemented a pNFS server two years ago, but that was a failure, due > to > terrible performance. (Using a clustered file system as a storage > backend would > make multiple NFS servers/MDSs more feasible, but it didn't work.) >=20 > rick OK, I think I understand, thank you for the explanation! So you could say that this enhancement is more about the performance benifit of scaling out, rather than resiliance/tolerance? /K