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 0EC3F9E74 for ; Wed, 2 May 2012 01:57:30 +0000 (UTC) Received: (qmail 73981 invoked by uid 500); 2 May 2012 01:57:27 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 73909 invoked by uid 500); 2 May 2012 01:57:27 -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 73901 invoked by uid 99); 2 May 2012 01:57:27 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 02 May 2012 01:57:27 +0000 X-ASF-Spam-Status: No, hits=3.5 required=5.0 tests=HTML_MESSAGE,RCVD_IN_DNSWL_NONE,SPF_PASS,URI_HEX X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: local policy) Received: from [208.113.200.5] (HELO homiemail-a58.g.dreamhost.com) (208.113.200.5) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 02 May 2012 01:57:20 +0000 Received: from homiemail-a58.g.dreamhost.com (localhost [127.0.0.1]) by homiemail-a58.g.dreamhost.com (Postfix) with ESMTP id 927617D805B for ; Tue, 1 May 2012 18:56:59 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=thelastpickle.com; h=from :mime-version:content-type:subject:date:in-reply-to:to :references:message-id; q=dns; s=thelastpickle.com; b=ojxKrPfbdQ HEHCGc/+bKKUogIVpJXE37JXxqCFaj9wDuoGR/vawfZQO33FQjqoY7CEO/stQ7Uw hycByImoKQAdVIZ4josVHso3Bqe88FMLHyTNy5iasXr5TMCA78FScoyrtcRHByvM yu6HS4ndzRHrdpypb8W9toDi33w2Lot5c= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=thelastpickle.com; h=from :mime-version:content-type:subject:date:in-reply-to:to :references:message-id; s=thelastpickle.com; bh=VNjlsrv6MnEOLfdh ++nNFEIRt4s=; b=YBm5xYSDzH9cggADXHt0lid+9Nzgl1p+h0P3N56tiRoWPx3i OSUDwJoCYB3nxDvy5DgGv+3KU1NoaMeSKVhMxw9N3fu7T1URr5PKLpmkCWVEXYCw XiJVywhzEle1MYRrYS8TNtwQLWnGUozxNV65hnNCxzzDzQkgbRZ9xS5Xv3U= Received: from [10.8.0.150] (unknown [72.28.97.147]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: aaron@thelastpickle.com) by homiemail-a58.g.dreamhost.com (Postfix) with ESMTPSA id E775A7D8058 for ; Tue, 1 May 2012 18:56:58 -0700 (PDT) From: aaron morton Mime-Version: 1.0 (Apple Message framework v1257) Content-Type: multipart/alternative; boundary="Apple-Mail=_A5D500A0-8993-41E2-9C76-F8B0E797AEE4" Subject: Re: Cassandra backup queston regarding commitlogs Date: Wed, 2 May 2012 13:56:51 +1200 In-Reply-To: <1335916962042-7518544.post@n2.nabble.com> To: user@cassandra.apache.org References: <1335618246414-7508823.post@n2.nabble.com> <124E3CF9-A7C8-474B-B152-D492041386C3@thelastpickle.com> <1335765747657-7512499.post@n2.nabble.com> <900C4868-355B-446A-BE84-21DE5C891342@thelastpickle.com> <1335823963584-7515217.post@n2.nabble.com> <5C8C4C22-AEEF-490C-B88A-353D9527EFA3@thelastpickle.com> <1335838672669-7515679.post@n2.nabble.com> <1335916962042-7518544.post@n2.nabble.com> Message-Id: <53339104-3364-46E3-A20A-5C8EB18EBBAF@thelastpickle.com> X-Mailer: Apple Mail (2.1257) --Apple-Mail=_A5D500A0-8993-41E2-9C76-F8B0E797AEE4 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii If you delete the commit logs you are rolling back to exactly what was = in the snapshot. When you take a snapshot it flushes the memtables = first, so there is nothing in the commit log that is not in the = snapshot. Rolling back to a snapshot is rollback to that point in time.=20= If you want to restore to any point in time you need snapshots + = incremental snapshot + commit log (for things that have not made it to = sstables). Otherwise there is a potential loss of data that has not been = flushed to disk. This is different to what the DS docs are talking = about. I'm not sure why they are saying delete the commit log, try = asking on their forum http://www.datastax.com/support-forums/ Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 2/05/2012, at 12:02 PM, Roshan wrote: > Any help regarding this is appreciated. >=20 > -- > View this message in context: = http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Cassandra= -backup-queston-regarding-commitlogs-tp7508823p7518544.html > Sent from the cassandra-user@incubator.apache.org mailing list archive = at Nabble.com. --Apple-Mail=_A5D500A0-8993-41E2-9C76-F8B0E797AEE4 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=us-ascii If = you delete the commit logs you are rolling back to exactly what was in = the snapshot. When you take a snapshot it flushes the memtables first, = so there is nothing in the commit log that is not in the snapshot. = Rolling back to a snapshot is rollback to that point in = time. 

If you want to restore to any point in = time you need snapshots + incremental snapshot + commit log (for things = that have not made it to sstables). Otherwise there is a potential loss = of data that has not been flushed to disk. This is different to what the = DS docs are talking about. I'm not sure why they are saying delete the = commit log, try asking on their forum http://www.datastax.com/s= upport-forums/

Cheers

http://www.thelastpickle.com

On 2/05/2012, at 12:02 PM, Roshan wrote:

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