From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dimitri Maziuk Subject: Re: Understanding Ceph Date: Thu, 24 Jan 2013 15:45:58 -0600 Message-ID: <5101AB96.6030708@bmrb.wisc.edu> References: <50FAC92C.8030709@bmrb.wisc.edu> <50FAE116.2010504@gmail.com> <50FC1DCF.8010304@bmrb.wisc.edu> <51007C0C.2030107@bmrb.wisc.edu> <51013D5F.7090105@bmrb.wisc.edu> <51015318.8000404@bmrb.wisc.edu> <51017A4D .2000901@inktank.com> <51018454.1050101@bmrb.wisc.edu> <5101A275.5070408@inktank.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig778673C41640E1B60CB4DC99" Return-path: Received: from cowfish.bmrb.wisc.edu ([144.92.167.220]:47068 "EHLO mail.bmrb.wisc.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752278Ab3AXVqI (ORCPT ); Thu, 24 Jan 2013 16:46:08 -0500 In-Reply-To: <5101A275.5070408@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Dan Mick Cc: "ceph-devel@vger.kernel.org" , john.wilkins@inktank.com, sam.lang@inktank.com This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig778673C41640E1B60CB4DC99 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 01/24/2013 03:07 PM, Dan Mick wrote: =2E.. > Yeah; it's probably mostly just that one-OSD configurations are so > uncommon that we never special-cased that small user set. Also, you ca= n > run with a cluster in that state forever (well, until that one OSD dies= > at least); I do that regularly with the default vstart.sh local test > cluster Well, this goes back to the quick start guide: to me a more natural way to start is with one host, then add another. That's what I was trying to do, however, the quick start page ends with "When your cluster echoes back HEALTH_OK, you may begin using Ceph." and that doesn't happen with one host: you get "384 pgs stuck unclean" instead of "HEALTH_OK". To me that means I may *not* begin using ceph. I did run "ceph osd pool set ... size 1" on each of the 3 default pools, verified that it took with "ceph osd dump | grep 'rep size'", and gave it a good half hour to settle. I still got "384 pgs stuck unclean" from "ceph health". So I re-done it with 2 OSDs and got the expected HEALTH_OK right from the start. John, a) a note saying "if you have only one OSD you won't get HEALTH_OK until you add another one; you can start using the cluster" may be a useful addition to the quick start, b) more importantly, if there are any plans to write more quickstart pages, I'd love to see the "add another OSD (MDS, MON) to an existing pool in 5 minutes". Thanks all, --=20 Dimitri Maziuk Programmer/sysadmin BioMagResBank, UW-Madison -- http://www.bmrb.wisc.edu --------------enig778673C41640E1B60CB4DC99 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.14 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iD8DBQFRAaufxzG8ttqkbbgRAvLTAKC9S3TKnVsCNoYFufKKRDZCWYUIMwCgtRhG iUJI3fYLNv2AegWiQaNtY9M= =G4yT -----END PGP SIGNATURE----- --------------enig778673C41640E1B60CB4DC99--