Return-Path: X-Original-To: apmail-hadoop-user-archive@minotaur.apache.org Delivered-To: apmail-hadoop-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 BD6BF18028 for ; Wed, 20 May 2015 01:21:33 +0000 (UTC) Received: (qmail 47758 invoked by uid 500); 20 May 2015 01:21:26 -0000 Delivered-To: apmail-hadoop-user-archive@hadoop.apache.org Received: (qmail 47650 invoked by uid 500); 20 May 2015 01:21:26 -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 47639 invoked by uid 99); 20 May 2015 01:21:26 -0000 Received: from Unknown (HELO spamd4-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 20 May 2015 01:21:26 +0000 Received: from localhost (localhost [127.0.0.1]) by spamd4-us-west.apache.org (ASF Mail Server at spamd4-us-west.apache.org) with ESMTP id 35016C11BA for ; Wed, 20 May 2015 01:21:26 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd4-us-west.apache.org X-Spam-Flag: NO X-Spam-Score: 2.98 X-Spam-Level: ** X-Spam-Status: No, score=2.98 tagged_above=-999 required=6.31 tests=[HTML_MESSAGE=3, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=disabled Received: from mx1-eu-west.apache.org ([10.40.0.8]) by localhost (spamd4-us-west.apache.org [10.40.0.11]) (amavisd-new, port 10024) with ESMTP id fOPd1UY4X5mV for ; Wed, 20 May 2015 01:21:20 +0000 (UTC) Received: from mail-oi0-f46.google.com (mail-oi0-f46.google.com [209.85.218.46]) by mx1-eu-west.apache.org (ASF Mail Server at mx1-eu-west.apache.org) with ESMTPS id 7B58120C38 for ; Wed, 20 May 2015 01:21:19 +0000 (UTC) Received: by oihb9 with SMTP id b9so24809901oih.3 for ; Tue, 19 May 2015 18:21:17 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:content-type; bh=WiSaahb7kHw84mvp5v5pP+zHxwK4S6NXWjOhrhjXn9E=; b=Kjclgr7aPkdv9K0wKckhEbKo2VIGhIQ7pYwIfLOLd+/dAODT0tACjLrNYWWCVm32gm pWwfy2Ss1RCJ1a1xvx3yUwOEf1gbbbpWchZ/+k4gdszQmV3OVTf7lguMrbpkDYqQhmhm Jym+Xyze3Oq7TdiMV+j5tIG38XbPcWX2dpGKYvKStzGcZIQQxMM+69pgchf1rJkvm+5Z CAzekrO+cTonMTKUCUTOoi1L+zM6aoljNQflG6x7tIukXWmD3A+2fzyrMu4CBTzvghWA N8sU1iEqP1Ax2y3MnbmHD4fN6IQ1Tyz5hHmJsd3SYkxNwyuo0UU9k+04tVw/3F3Y6vcm t36w== X-Gm-Message-State: ALoCoQmsIPh0trfbLaV79imbn9p0yAXT/wnq5z0BdxLf9IG3Uhun2VcPPTIOJjpk42Ea9sLlQo6G MIME-Version: 1.0 X-Received: by 10.182.126.40 with SMTP id mv8mr19790464obb.22.1432084877669; Tue, 19 May 2015 18:21:17 -0700 (PDT) Received: by 10.202.67.195 with HTTP; Tue, 19 May 2015 18:21:17 -0700 (PDT) In-Reply-To: References: Date: Wed, 20 May 2015 08:21:17 +0700 Message-ID: Subject: Re: how namenode decided which datanode are ready for a client From: Himawan Mahardianto To: user@hadoop.apache.org Content-Type: multipart/alternative; boundary=e89a8fb1f7646c120b0516793e8c --e89a8fb1f7646c120b0516793e8c Content-Type: text/plain; charset=UTF-8 but on what category datanode are choosen by namenode, if some client want to write some data(block) on it via HDFS how namenode distinguish on one datanode and the other if only I just have one rack, so rack awareness feature are unused On Tue, May 19, 2015 at 3:56 PM, rajesh damera wrote: > Namenode usually checks for the jobs running on the datanodes, of which > tasktrackers keep a track of and decides if it still busy running a task. > On May 19, 2015 14:23, "rajesh damera" wrote: > >> Datanode availability is monitored and decided by Namenode. You usually >> get permissions, based on the type of user you are, to use a certain number >> of nodes to run your jobs. These limitations are set by administrators at >> user level >> >> Warm regards >> Rajesh Damera >> On May 19, 2015 14:08, "Himawan Mahardianto" >> wrote: >> >>> Hi guys, I know that every datanode where sending heartbeat to prove >>> that their alive but what method are used by namenode to decide which >>> datanode are available to client if all datanode where available? >>> >>> Best Regards >>> >>> >> --e89a8fb1f7646c120b0516793e8c Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
but on what category datanode are choosen by namenode= , if some client want to write some data(block) on it via HDFS
how= namenode distinguish on one datanode and the other if only I just have one= rack, so rack awareness feature are unused

On Tue, May 19, 2015 at 3:56 PM, rajesh = damera <d.rajesh15@gmail.com> wrote:

Namenode usually checks for= the jobs running on the datanodes, of which tasktrackers keep a track of a= nd decides if it still busy running a task.

On May 19, 2015 14:23, "rajesh damera"= <d.rajesh15@g= mail.com> wrote:

Datanode availability is monitored an= d decided by Namenode. You usually get permissions, based on the type of us= er you are, to use a certain number of nodes to run your jobs. These limita= tions are set by administrators at user level

Warm regards
Rajesh Damera

On May 19, 2015 14:08, "Himawan Mahardianto= " <mahar= dianto@ugm.ac.id> wrote:
Hi guys,=C2=A0I know that= every datanode where sending heartbeat to prove that their alive but=C2=A0= what method are used by namenode to decide which datanode are available to = client if all datanode where available?

Best Regard= s
=C2=A0

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