Return-Path: X-Original-To: apmail-cassandra-user-archive@www.apache.org Delivered-To: apmail-cassandra-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 1739510AE4 for ; Wed, 28 Aug 2013 20:54:46 +0000 (UTC) Received: (qmail 31830 invoked by uid 500); 28 Aug 2013 20:54:43 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 31808 invoked by uid 500); 28 Aug 2013 20:54:43 -0000 Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@cassandra.apache.org Delivered-To: mailing list user@cassandra.apache.org Received: (qmail 31800 invoked by uid 99); 28 Aug 2013 20:54:43 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 28 Aug 2013 20:54:43 +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 (nike.apache.org: domain of muntasir.raihan@gmail.com designates 209.85.192.179 as permitted sender) Received: from [209.85.192.179] (HELO mail-pd0-f179.google.com) (209.85.192.179) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 28 Aug 2013 20:54:37 +0000 Received: by mail-pd0-f179.google.com with SMTP id v10so6752559pde.38 for ; Wed, 28 Aug 2013 13:54:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=5AU7dCKXdE+NyB418dmt+Qf7NlS7s/Zn33uun/yPfw8=; b=YR0vCmNY2DjJu5sHEeIAVnRz7y1nl+OutIeG89lBQGk7/46tBeGf3yvGrwxiZYTnKW +dgjH8pGr8PNDeIRoMvVo0o+BsDubZJcukqTSZev2hHV1ebH3Ntb108YUs+dy/nqzEu+ zBsMpFirXp7jE5ZL0OfZLosg50kyoxrXWRHoa7vyRqvayek1UkgbjOJaufoOSfEIDedJ JSlGDLEFok8v0lW7XJlPaXny+RVIfSPy0kP2UgnvaykvaTPpCo+pHFbSGH9VOc6RSq0T ILmGku/fI9Jxr5Ho6uCM9U4hJl7JvYV2Da5yXjecJNPON0221fmOhVJrGicj9vhcbrVq Tb1Q== MIME-Version: 1.0 X-Received: by 10.66.242.17 with SMTP id wm17mr516642pac.102.1377723256802; Wed, 28 Aug 2013 13:54:16 -0700 (PDT) Received: by 10.70.131.17 with HTTP; Wed, 28 Aug 2013 13:54:16 -0700 (PDT) In-Reply-To: References: Date: Wed, 28 Aug 2013 15:54:16 -0500 Message-ID: Subject: Re: configuring read write quorums in cassandra From: Muntasir Raihan Rahman To: user@cassandra.apache.org Content-Type: text/plain; charset=ISO-8859-1 X-Virus-Checked: Checked by ClamAV on apache.org Thanks! Muntasir. On Wed, Aug 28, 2013 at 3:52 PM, Robert Coli wrote: > On Wed, Aug 28, 2013 at 1:48 PM, Muntasir Raihan Rahman > wrote: >> >> Let us say I set read consistency level = ONE, and I am running the >> system for a while. Then I want to change the read consistency level >> to TWO so that reads now wait to hear back from 2 replicas instead of >> 1 before responding to the client. > > > In general, TWO is only for users who really know what they are doing. Most > users will use ONE or *_QUORUM. > > But changing it is just a matter of changing the ConsistencyLevel of your > new requests, in your application code. > > Changing *replication factor* is a bit more involved. > > =Rob > -- Best Regards Muntasir Raihan Rahman Email: muntasir.raihan@gmail.com Department of Computer Science, University of Illinois Urbana Champaign, 3111 Siebel Center, 201 N. Goodwin Avenue, Urbana, IL 61801