Return-Path: X-Original-To: apmail-hbase-user-archive@www.apache.org Delivered-To: apmail-hbase-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 D150110543 for ; Thu, 13 Mar 2014 20:49:40 +0000 (UTC) Received: (qmail 44686 invoked by uid 500); 13 Mar 2014 20:49:35 -0000 Delivered-To: apmail-hbase-user-archive@hbase.apache.org Received: (qmail 44611 invoked by uid 500); 13 Mar 2014 20:49:35 -0000 Mailing-List: contact user-help@hbase.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@hbase.apache.org Delivered-To: mailing list user@hbase.apache.org Received: (qmail 44603 invoked by uid 99); 13 Mar 2014 20:49:35 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 13 Mar 2014 20:49:35 +0000 X-ASF-Spam-Status: No, hits=1.5 required=5.0 tests=HTML_MESSAGE,RCVD_IN_DNSWL_LOW,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of storey.jeff@gmail.com designates 209.85.128.171 as permitted sender) Received: from [209.85.128.171] (HELO mail-ve0-f171.google.com) (209.85.128.171) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 13 Mar 2014 20:49:29 +0000 Received: by mail-ve0-f171.google.com with SMTP id cz12so1723471veb.16 for ; Thu, 13 Mar 2014 13:49:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type; bh=RVgKjzLh1+APKKHC8zEFoJrqVA9clUKrqo2bNc7NpQA=; b=N4tt3U8XOaGEUPdw3Eh/4yRjbAI57BygD1QfTCBh/m8Sfw9gZtR1DLyoddzdr8vqLx na2VBONZriZr5SEmbbHO5+WKgZjj7s2KypfYnTeNj+p3XUScNtPvX4jvSl1JC43YXyx3 YzZ9TPDMvR/GvYnPFXzDAVo7QgRvz0xt1x+Ao9gjS/OHKUqWhasw+e8xh0WyVnXFGTJS Q9Q+rJUc5FTxthHfSes9NUdsLe0qyLIO4txTvqdGzlzGcLzXALNi1r1NPsVzqm/ylZnW S5eT1M7VObB2CjQ6sza2xWSTSrI3W9/MfugE0TfdjVxTe8rZeL7Ebd7qYegZMtFINdeo Daow== MIME-Version: 1.0 X-Received: by 10.220.11.141 with SMTP id t13mr2506991vct.30.1394743747873; Thu, 13 Mar 2014 13:49:07 -0700 (PDT) Received: by 10.220.148.197 with HTTP; Thu, 13 Mar 2014 13:49:07 -0700 (PDT) Date: Thu, 13 Mar 2014 16:49:07 -0400 Message-ID: Subject: Region server failover From: Jeff Storey To: user@hbase.apache.org Content-Type: multipart/alternative; boundary=001a11c3c970a5116c04f483150a X-Virus-Checked: Checked by ClamAV on apache.org --001a11c3c970a5116c04f483150a Content-Type: text/plain; charset=ISO-8859-1 I'm still somewhat new to HBase and I'm trying to understand possibilities for region server failover. If I have a region server that goes down, it looks like I won't have any access to that region's data until a backup server comes online. I read that I can reduce the zookeeper timeout to minimize that time down, but in a system that is meant to be highly available, it seems like this could be cause for concern since a portion of the data will be entirely inaccessible. Is there a way to have a secondary read-only region server that becomes the new primary region server in the event of a failure? This way that data will always be accessible unless all of the region server backups fail? Or are there other ways to replicate region data to avoid loss of access for possibly several minutes to that data if the server goes down? Thanks, Jeff --001a11c3c970a5116c04f483150a--