Return-Path: X-Original-To: apmail-zookeeper-user-archive@www.apache.org Delivered-To: apmail-zookeeper-user-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 656B36DA1 for ; Thu, 9 Jun 2011 23:05:16 +0000 (UTC) Received: (qmail 31256 invoked by uid 500); 9 Jun 2011 23:05:16 -0000 Delivered-To: apmail-zookeeper-user-archive@zookeeper.apache.org Received: (qmail 31211 invoked by uid 500); 9 Jun 2011 23:05:15 -0000 Mailing-List: contact user-help@zookeeper.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@zookeeper.apache.org Delivered-To: mailing list user@zookeeper.apache.org Received: (qmail 31192 invoked by uid 99); 9 Jun 2011 23:05:15 -0000 Received: from minotaur.apache.org (HELO minotaur.apache.org) (140.211.11.9) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 09 Jun 2011 23:05:15 +0000 Received: from localhost (HELO mail-ew0-f42.google.com) (127.0.0.1) (smtp-auth username breed, mechanism plain) by minotaur.apache.org (qpsmtpd/0.29) with ESMTP; Thu, 09 Jun 2011 23:05:15 +0000 Received: by ewy2 with SMTP id 2so957234ewy.15 for ; Thu, 09 Jun 2011 16:05:13 -0700 (PDT) MIME-Version: 1.0 Received: by 10.213.3.84 with SMTP id 20mr1127097ebm.12.1307660713798; Thu, 09 Jun 2011 16:05:13 -0700 (PDT) Received: by 10.213.21.137 with HTTP; Thu, 9 Jun 2011 16:05:13 -0700 (PDT) In-Reply-To: References: Date: Thu, 9 Jun 2011 16:05:13 -0700 Message-ID: Subject: Re: Mounting a remote Zookeeper From: Benjamin Reed To: user@zookeeper.apache.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable this is a small nit, but i think the partition proposal works a bit more like a mount point than your proposal. when you mount a file system, the mount isn't transparent. two mounted file systems can have files with the same inode number, for example. you also can't do some things like a rename across file system boundaries. in your proposal, what happens if an a client creates an ephemeral node on the remote ZK cluster. who does the failure detection and clean up? it also wasn't clear what happens when a client does a read on the remote ZK cluster. does the read always get forwarded to the remote cluster? also what happens if the request to the remote cluster hangs? thanx ben On Thu, Jun 9, 2011 at 11:41 AM, Alexander Shraer w= rote: > Hi, > > We're considering working on a new feature that will allow "mounting" par= t of the namespace of one ZK cluster into another ZK cluster. The goal is e= ssentially to be able to partition a ZK namespace while preserving current = ZK semantics as much as possible. > More details are here: http://wiki.apache.org/hadoop/ZooKeeper/MountRemot= eZookeeper > > It would be great to get your feedback and especially please let us know = if you think your application can benefit from this feature. > > Thanks, > Alex Shraer and Eddie Bortnikov > > >