Return-Path: X-Original-To: apmail-hadoop-hdfs-dev-archive@minotaur.apache.org Delivered-To: apmail-hadoop-hdfs-dev-archive@minotaur.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id A75FC1895C for ; Thu, 20 Aug 2015 14:35:21 +0000 (UTC) Received: (qmail 11915 invoked by uid 500); 20 Aug 2015 14:35:21 -0000 Delivered-To: apmail-hadoop-hdfs-dev-archive@hadoop.apache.org Received: (qmail 11819 invoked by uid 500); 20 Aug 2015 14:35:20 -0000 Mailing-List: contact hdfs-dev-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: hdfs-dev@hadoop.apache.org Delivered-To: mailing list hdfs-dev@hadoop.apache.org Received: (qmail 11808 invoked by uid 99); 20 Aug 2015 14:35:20 -0000 Received: from mail-relay.apache.org (HELO mail-relay.apache.org) (140.211.11.15) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 20 Aug 2015 14:35:20 +0000 Received: from mail-io0-f181.google.com (mail-io0-f181.google.com [209.85.223.181]) by mail-relay.apache.org (ASF Mail Server at mail-relay.apache.org) with ESMTPSA id A69791A0046 for ; Thu, 20 Aug 2015 14:35:20 +0000 (UTC) Received: by iodt126 with SMTP id t126so48227381iod.2 for ; Thu, 20 Aug 2015 07:35:20 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.107.12.33 with SMTP id w33mr3400814ioi.110.1440081320071; Thu, 20 Aug 2015 07:35:20 -0700 (PDT) Received: by 10.107.146.133 with HTTP; Thu, 20 Aug 2015 07:35:19 -0700 (PDT) Received: by 10.107.146.133 with HTTP; Thu, 20 Aug 2015 07:35:19 -0700 (PDT) In-Reply-To: References: Date: Thu, 20 Aug 2015 20:05:19 +0530 Message-ID: Subject: Re: How to bring standby namenode to active mode in case of active host node down? From: Vinayakumar B To: hdfs-dev@hadoop.apache.org Content-Type: multipart/alternative; boundary=001a113f9d0687dcff051dbf0f6b --001a113f9d0687dcff051dbf0f6b Content-Type: text/plain; charset=UTF-8 Actually SSH fencing was introduced before QuorumJournal was there to ensure only one active writer at all times. If you are using QuorumJournal for shared edits.. you dont need to configure SSH fencing. QuorumJournal will ensure its allowing only one writer at a time. -Vinay --001a113f9d0687dcff051dbf0f6b--