From mboxrd@z Thu Jan 1 00:00:00 1970 From: brady Subject: Re: Character limit for rbd block device Date: Tue, 27 Nov 2012 13:32:54 -0800 Message-ID: <50B53186.1040807@lamphost.com> References: <50B404DA.50805@lamphost.com> <50B40ED5.7050307@inktank.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from tux2.lamphost.net ([69.43.195.67]:45216 "EHLO tux2.lamphost.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754788Ab2K0Vdr (ORCPT ); Tue, 27 Nov 2012 16:33:47 -0500 In-Reply-To: <50B40ED5.7050307@inktank.com> Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Josh Durgin Cc: ceph-devel@vger.kernel.org On 11/26/2012 04:52 PM, Josh Durgin wrote: > On 11/26/2012 04:10 PM, brady wrote: >> Hello, >> I have a general question. Is there a specific character limit for >> rbd block devices? In attempting to map a block device with a name that >> is 36 characters or more, I am getting the following error: >> >> rbd map (36+ character name) --user admin --secret /etc/ceph/keyring.key >> add failed: (2) No such file or directory >> >> When using the same command to map a device with 35 characters or >> less, the device is mapped as expected. Any insight into this issue >> would be greatly appreciated. >> >> -Brady > > Which kernel version are you using? > > A year ago there was a 40-char limit on objects names in the kernel's > libceph module, hence the failure at 36 char rbd image names (36 char > name + ".rbd" is the format 1 header object name). > > This was extended to a 96-char limit in linux 3.2. There's no real limit > in userspace still (http://tracker.newdream.net/issues/1701). > > Josh > Thanks, Josh. This information was exactly what we were looking for. Looks like a version issue that we will need to work around. Thanks again! Brady > -- > 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