Return-Path: X-Original-To: apmail-hadoop-hdfs-user-archive@minotaur.apache.org Delivered-To: apmail-hadoop-hdfs-user-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 727A4F0FC for ; Sun, 21 Apr 2013 10:01:54 +0000 (UTC) Received: (qmail 67812 invoked by uid 500); 21 Apr 2013 10:01:49 -0000 Delivered-To: apmail-hadoop-hdfs-user-archive@hadoop.apache.org Received: (qmail 67350 invoked by uid 500); 21 Apr 2013 10:01:48 -0000 Mailing-List: contact user-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@hadoop.apache.org Delivered-To: mailing list user@hadoop.apache.org Received: (qmail 67330 invoked by uid 99); 21 Apr 2013 10:01:47 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Sun, 21 Apr 2013 10:01:47 +0000 X-ASF-Spam-Status: No, hits=-0.0 required=5.0 tests=RCVD_IN_DNSWL_NONE,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: local policy) Received: from [212.27.42.5] (HELO smtp5-g21.free.fr) (212.27.42.5) by apache.org (qpsmtpd/0.29) with ESMTP; Sun, 21 Apr 2013 10:01:42 +0000 Received: from zimbra59-e10.priv.proxad.net (unknown [172.20.243.209]) by smtp5-g21.free.fr (Postfix) with ESMTP id A55E6D48091 for ; Sun, 21 Apr 2013 12:01:15 +0200 (CEST) Date: Sun, 21 Apr 2013 12:01:14 +0200 (CEST) From: anthony.lelong@free.fr To: user@hadoop.apache.org Message-ID: <509544930.86297714.1366538474583.JavaMail.root@zimbra59-e10.priv.proxad.net> In-Reply-To: <713819079.86262430.1366537492939.JavaMail.root@zimbra59-e10.priv.proxad.net> Subject: HDFS load-balancing MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [2a01:e35:8b37:62d0:599:5576:b10f:d18f] X-Mailer: Zimbra 7.2.0-GA2598 (ZimbraWebClient - FF3.0 (Win)/7.2.0-GA2598) X-Authenticated-User: anthony.lelong@free.fr X-Virus-Checked: Checked by ClamAV on apache.org Hello everybody. I am wondering how HDFS deals with load balancing. I mean, there is on primary namenode and only one secondary namenode (if I well understood the documentation). Is that right? But with only one server answering all requests, I can't imagine it could be enough. I have also read that facebook use that FS so it might be possible, isn't it? Regards. Anthony.