From mboxrd@z Thu Jan 1 00:00:00 1970 From: Erik McCormick Subject: Re: [ceph-users] removing cluster name support Date: Tue, 7 Nov 2017 01:39:00 -0500 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: Received: from mail-qk0-f180.google.com ([209.85.220.180]:47604 "EHLO mail-qk0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753323AbdKGGjC (ORCPT ); Tue, 7 Nov 2017 01:39:02 -0500 Received: by mail-qk0-f180.google.com with SMTP id m189so14011531qke.4 for ; Mon, 06 Nov 2017 22:39:01 -0800 (PST) In-Reply-To: Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Sage Weil Cc: ceph-devel@vger.kernel.org, ceph-users@ceph.com On Fri, Jun 9, 2017 at 12:30 PM, Sage Weil wrote: > On Fri, 9 Jun 2017, Erik McCormick wrote: >> On Fri, Jun 9, 2017 at 12:07 PM, Sage Weil wrote: >> > On Thu, 8 Jun 2017, Sage Weil wrote: >> >> Questions: >> >> >> >> - Does anybody on the list use a non-default cluster name? >> >> - If so, do you have a reason not to switch back to 'ceph'? >> > >> > It sounds like the answer is "yes," but not for daemons. Several users use >> > it on the client side to connect to multiple clusters from the same host. >> > >> >> I thought some folks said they were running with non-default naming >> for daemons, but if not, then count me as one who does. This was >> mainly a relic of the past, where I thought I would be running >> multiple clusters on one host. Before long I decided it would be a bad >> idea, but by then the cluster was already in heavy use and I couldn't >> undo it. >> >> I will say that I am not opposed to renaming back to ceph, but it >> would be great to have a documented process for accomplishing this >> prior to deprecation. Even going so far as to remove --cluster from >> deployment tools will leave me unable to add OSDs if I want to upgrade >> when Luminous is released. > > Note that even if the tool doesn't support it, the cluster name is a > host-local thing, so you can always deploy ceph-named daemons on other > hosts. > > For an existing host, the removal process should be as simple as > > - stop the daemons on the host > - rename /etc/ceph/foo.conf -> /etc/ceph/ceph.conf > - rename /var/lib/ceph/*/foo-* -> /var/lib/ceph/*/ceph-* (this mainly > matters for non-osds, since the osd dirs will get dynamically created by > ceph-disk, but renaming will avoid leaving clutter behind) > - comment out the CLUSTER= line in /etc/{sysconfig,default}/ceph (if > you're on jewel) > - reboot > > If you wouldn't mind being a guinea pig and verifying that this is > sufficient that would be really helpful! We'll definitely want to > document this process. > > Thanks! > sage > Sitting here in a room with you reminded me I dropped the ball on feeding back on the procedure. I did this a couple weeks ago and it worked fine. I had a few problems with OSDs not wanting to unmount, so I had to reboot each node along the way. I just used it as an excuse to run updates. -Erik > >> >> > Nobody is colocating multiple daemons from different clusters on the same >> > host. Some have in the past but stopped. If they choose to in the >> > future, they can customize the systemd units themselves. >> > >> > The rbd-mirror daemon has a similar requirement to talk to multiple >> > clusters as a client. >> > >> > This makes me conclude our current path is fine: >> > >> > - leave existing --cluster infrastructure in place in the ceph code, but >> > - remove support for deploying daemons with custom cluster names from the >> > deployment tools. >> > >> > This neatly avoids the systemd limitations for all but the most >> > adventuresome admins and avoid the more common case of an admin falling >> > into the "oh, I can name my cluster? cool! [...] oh, i have to add >> > --cluster rover to every command? ick!" trap. >> > >> >> Yeah, that was me in 2012. Oops. >> >> -Erik >> >> > sage >> > _______________________________________________ >> > ceph-users mailing list >> > ceph-users@lists.ceph.com >> > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> -- >> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >>