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 CD24FD4FE for ; Thu, 23 Aug 2012 18:06:22 +0000 (UTC) Received: (qmail 1102 invoked by uid 500); 23 Aug 2012 18:06:20 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 1081 invoked by uid 500); 23 Aug 2012 18:06:20 -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 1070 invoked by uid 99); 23 Aug 2012 18:06:20 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 23 Aug 2012 18:06:20 +0000 X-ASF-Spam-Status: No, hits=-0.1 required=5.0 tests=HTML_MESSAGE,RCVD_IN_DNSWL_MED,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: local policy) Received: from [216.82.249.131] (HELO mail28.messagelabs.com) (216.82.249.131) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 23 Aug 2012 18:06:15 +0000 X-Env-Sender: Bryce.Godfrey@azaleos.com X-Msg-Ref: server-14.tower-28.messagelabs.com!1345745153!24808248!1 X-Originating-IP: [96.31.162.44] X-StarScan-Received: X-StarScan-Version: 6.6.1.3; banners=-,-,- X-VirusChecked: Checked Received: (qmail 4468 invoked from network); 23 Aug 2012 18:05:53 -0000 Received: from unknown (HELO smtp.azaleos.net) (96.31.162.44) by server-14.tower-28.messagelabs.com with AES128-SHA encrypted SMTP; 23 Aug 2012 18:05:53 -0000 Received: from FISH-MBX-02.azaleos.net ([fe80::4918:2597:a7be:1075]) by FISH-HUB-01.azaleos.net ([fe80::ecdb:527f:9348:37e%11]) with mapi id 14.03.0047.000; Thu, 23 Aug 2012 11:05:52 -0700 From: Bryce Godfrey To: "user@cassandra.apache.org" Subject: RE: Expanding cluster to include a new DR datacenter Thread-Topic: Expanding cluster to include a new DR datacenter Thread-Index: Ac2ApIfFaOPYziBeTeqfUNwTaymK8QAapDIAABKmdlA= Date: Thu, 23 Aug 2012 18:05:51 +0000 Message-ID: <054A19B0E41FDD43A58D2CC1E8C3FF5B1E637B3A@FISH-MBX-02.azaleos.net> References: <054A19B0E41FDD43A58D2CC1E8C3FF5B1E637337@FISH-MBX-02.azaleos.net> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.20.0.100] Content-Type: multipart/alternative; boundary="_000_054A19B0E41FDD43A58D2CC1E8C3FF5B1E637B3AFISHMBX02azaleo_" MIME-Version: 1.0 X-Virus-Checked: Checked by ClamAV on apache.org --_000_054A19B0E41FDD43A58D2CC1E8C3FF5B1E637B3AFISHMBX02azaleo_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Thanks for the information! Answers my questions. From: Tyler Hobbs [mailto:tyler@datastax.com] Sent: Wednesday, August 22, 2012 7:10 PM To: user@cassandra.apache.org Subject: Re: Expanding cluster to include a new DR datacenter If you didn't see this particular section, you may find it useful: http://w= ww.datastax.com/docs/1.1/operations/cluster_management#adding-a-data-center= -to-a-cluster Some comments inline: On Wed, Aug 22, 2012 at 3:43 PM, Bryce Godfrey > wrote: We are in the process of building out a new DR system in another Data Cente= r, and we want to mirror our Cassandra environment to that DR. I have a co= uple questions on the best way to do this after reading the documentation o= n the Datastax website. We didn't initially plan for this to be a DR setup= when first deployed a while ago due to budgeting, but now we need to. So = I'm just trying to nail down the order of doing this as well as any potenti= al issues. For the nodes, we don't plan on querying the servers in this DR until we fa= il over to this data center. We are going to have 5 similar nodes in the = DR, should I join them into the ring at token+1? Join them at token+10 just to leave a little space. Make sure you're using= LOCAL_QUORUM for your queries instead of regular QUORUM. All keyspaces are set to the replication strategy of SimpleStrategy. Can I= change the replication strategy after joining the new nodes in the DR to N= etworkTopologyStategy with the updated replication factor for each dr? Switch your keyspaces over to NetworkTopologyStrategy before adding the new= nodes. For the strategy options, just list the first dc until the second = is up (e.g. {main_dc: 3}). Lastly, is changing snitch from default of SimpleSnitch to RackInferringSni= tch going to cause any issues? Since its in the Cassandra.yaml file I assu= me a rolling restart to pick up the value would be ok? This is the first thing you'll want to do. Unless your node IPs would natu= rally put all nodes in a DC in the same rack, I recommend using PropertyFil= eSnitch, explicitly using the same rack. (I tend to prefer PFSnitch regard= less; it's harder to accidentally mess up.) A rolling restart is required = to pick up the change. Make sure to fill out cassandra-topology.properties= first if using PFSnitch. This is all on Cassandra 1.1.4, Thanks for any help! -- Tyler Hobbs DataStax --_000_054A19B0E41FDD43A58D2CC1E8C3FF5B1E637B3AFISHMBX02azaleo_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Thanks for the informatio= n!  Answers my questions.

 <= /p>

From: Tyler = Hobbs [mailto:tyler@datastax.com]
Sent: Wednesday, August 22, 2012 7:10 PM
To: user@cassandra.apache.org
Subject: Re: Expanding cluster to include a new DR datacenter

 

If you didn't see thi= s particular section, you may find it useful: http://www.datastax.com/docs/1.1/operations/cluster_management#adding-a-dat= a-center-to-a-cluster

Some comments inline:

On Wed, Aug 22, 2012 at 3:43 PM, Bryce Godfrey <<= a href=3D"mailto:Bryce.Godfrey@azaleos.com" target=3D"_blank">Bryce.Godfrey= @azaleos.com> wrote:

We are in the process of building out a new DR system in another D= ata Center, and we want to mirror our Cassandra environment to that DR.&nbs= p; I have a couple questions on the best way to do this after reading the documentation on the Datastax website.&nb= sp; We didn’t initially plan for this to be a DR setup when first dep= loyed a while ago due to budgeting, but now we need to.  So I’m = just trying to nail down the order of doing this as well as any potential issues.

 

For the nodes, we don’t plan on querying the servers in this= DR until we fail over to this data center.   We are going to hav= e 5 similar nodes in the DR, should I join them into the ring at token+1?


Join them at token+10 just to leave a little space.  Make sure you= 're using LOCAL_QUORUM for your queries instead of regular QUORUM.
 

 

All keyspaces are set to the replication strategy of SimpleStrateg= y.  Can I change the replication strategy after joining the new nodes = in the DR to NetworkTopologyStategy with the updated replication factor for each dr?


Switch your keyspaces over to NetworkTopologyStrategy before adding the new= nodes.  For the strategy options, just list the first dc until the se= cond is up (e.g. {main_dc: 3}).
 

 

Lastly, is changing snitch from default of SimpleSnitch to RackInf= erringSnitch going to cause any issues?  Since its in the Cassandra.ya= ml file I assume a rolling restart to pick up the value would be ok?


This is the first thing you'll want to do.  Unless your node IPs would= naturally put all nodes in a DC in the same rack, I recommend using Proper= tyFileSnitch, explicitly using the same rack.  (I tend to prefer PFSni= tch regardless; it's harder to accidentally mess up.)  A rolling restart is required to pick up the change. = Make sure to fill out cassandra-topology.properties first if using PFSnitc= h.
 

 

This is all on Cassandra 1.1.4, Thanks for any help!

 

 




--
Tyler Hobbs
DataStax=

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