Return-Path: X-Original-To: archive-asf-public-internal@cust-asf2.ponee.io Delivered-To: archive-asf-public-internal@cust-asf2.ponee.io Received: from cust-asf.ponee.io (cust-asf.ponee.io [163.172.22.183]) by cust-asf2.ponee.io (Postfix) with ESMTP id 2779F200BC5 for ; Tue, 22 Nov 2016 20:56:58 +0100 (CET) Received: by cust-asf.ponee.io (Postfix) id 262ED160B0C; Tue, 22 Nov 2016 19:56:58 +0000 (UTC) Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by cust-asf.ponee.io (Postfix) with SMTP id 498A1160AF1 for ; Tue, 22 Nov 2016 20:56:57 +0100 (CET) Received: (qmail 90938 invoked by uid 500); 22 Nov 2016 19:56:55 -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 90924 invoked by uid 99); 22 Nov 2016 19:56:55 -0000 Received: from pnap-us-west-generic-nat.apache.org (HELO spamd2-us-west.apache.org) (209.188.14.142) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 22 Nov 2016 19:56:55 +0000 Received: from localhost (localhost [127.0.0.1]) by spamd2-us-west.apache.org (ASF Mail Server at spamd2-us-west.apache.org) with ESMTP id 5E0FE1A9BA2 for ; Tue, 22 Nov 2016 19:56:55 +0000 (UTC) X-Virus-Scanned: Debian amavisd-new at spamd2-us-west.apache.org X-Spam-Flag: NO X-Spam-Score: 1.899 X-Spam-Level: * X-Spam-Status: No, score=1.899 tagged_above=-999 required=6.31 tests=[DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HTML_MESSAGE=2, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=disabled Authentication-Results: spamd2-us-west.apache.org (amavisd-new); dkim=pass (1024-bit key) header.d=winguzone.com Received: from mx1-lw-us.apache.org ([10.40.0.8]) by localhost (spamd2-us-west.apache.org [10.40.0.9]) (amavisd-new, port 10024) with ESMTP id F9xdadz-PqK2 for ; Tue, 22 Nov 2016 19:56:53 +0000 (UTC) Received: from sender163-mail.zoho.com (sender163-mail.zoho.com [74.201.84.163]) by mx1-lw-us.apache.org (ASF Mail Server at mx1-lw-us.apache.org) with ESMTPS id 215185FC6D for ; Tue, 22 Nov 2016 19:56:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1479844606; s=zoho; d=winguzone.com; i=vladyu@winguzone.com; h=Date:From:To:Message-Id:In-Reply-To:References:Subject:MIME-Version:Content-Type; l=5995; bh=C9viC6i1gOLTXoxihqqCP0kTQaih82iGgGJ2kfJWuLg=; b=TB1/gmBV8eei0392pp55YvnWS9RZzAqQTy1xDnP7u5Q9xdvMKoOsRaWtXdZxMdzA KeMd29j26t4LVDBoFhkY5mAV+OHhFu8o2RwmmaACluHXKsyf7JiHEb9Pl1AR4jArpis mz3zGY5VOBnAWd7HnSqu+xkQ7GRa2obC6gzcXPwo= Received: from mail.zoho.com by mx.zohomail.com with SMTP id 1479844606183335.19859485850213; Tue, 22 Nov 2016 11:56:46 -0800 (PST) Date: Tue, 22 Nov 2016 14:56:46 -0500 From: Vladimir Yudovin To: "user" Message-Id: <1588d9cb0dc.d0b70fe0332711.3210406394086239936@winguzone.com> In-Reply-To: References: Subject: Re: single instance failover MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_1047690_819220122.1479844606178" X-Priority: Medium User-Agent: Zoho Mail X-Mailer: Zoho Mail archived-at: Tue, 22 Nov 2016 19:56:58 -0000 ------=_Part_1047690_819220122.1479844606178 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Sorry, probably I didn't catch your setup fully. Would you like to use shared data folder for both nodes, assuming you never run two Cassandra process simultaneously? Well, I guess it's possible. Running two Cassandra instances on the same data folder together won't work, so prevent this situation, may be with some sort of file locking. >multinode Cassandra for Node B is not free Sure, but besides higher reliability you also get increase in read queries speed (with consistency ONE). Best regards, Vladimir Yudovin, Winguzone - Cloud Cassandra Hosting, Zero production time ---- On Tue, 22 Nov 2016 14:28:33 -0500Lou DeGenaro <lou.degenaro@gmail.com> wrote ---- Yes, change rpc_address to node B. Immutability aside, if Node A Cassandra and Node B Cassandra are using the same directory on the same shared filesystem, let's call it /cassandra/state/database, would that not be a problem? Or said differently, does not Node A need its own writable place /cassandra/state/database/nodeA and likewise /cassandra/state/database/nodeB for Node B's writable place? Multinode Cassandra may not always be available due to resource constraints. Presumably multinode Cassandra for Node B is not free: it takes up network, cpu, and replicated disk space, no? Lou. On 2016-11-22 11:10 (-0500), Vladimir Yudovin <v...@winguzone.com> wrote: > Hi Lou,> > > > > do you mean you set rpc_address (or broadcast_rpc_address) to Node_B_IP on second machine?> > > > > &gt;there would be potential database corruption, no?> > > Well, so SSTables are immutable, it can lead to unpredictable behavior, I guess. I don't believe anybody tested such setup before.> > > > > &gt;Is there any guidance on single instance failover?> > > I never saw one, the main Casandra idea that you build multinode cluster.> >% ------=_Part_1047690_819220122.1479844606178 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable =
Sorry, probably I didn't catch your setup fully.

Would you like to use shared data folder for both nod= es, assuming you never run two Cassandra process simultaneously?
<= div>Well, I guess it's possible. Running two Cassandra instances on the sam= e data folder together won't work, so prevent this situation, may be with s= ome sort of file locking.

>multinode Cas= sandra for Node B is not free
Sure, but besides higher re= liability you also get increase in read queries speed (with consistency ONE= ).

Best regards, Vladimir Yudovin= ,
Winguzone - Cloud Cassandra Hosting, Zero production time<= br>


---- On Tue, 22 Nov 2016 14:28:33 -0500Lou DeGenaro <= lou.degenaro@gmail.com> wrote ----

Yes, change rp= c_address to node B.
Immutability aside, if Node= A Cassandra and Node B Cassandra are using the same directory on the same = shared filesystem, let's call it /= cassandra/state/database, would that not be a problem?  Or said= differently, does not Node A need its own writable place /cassandra/state/database/nodeA and likewise= /cassandra/state/database/nodeB<= /span> for Node B's writable place?

Multinode Cassandra may not always be available due to r= esource constraints.  Presumably multinode Cas= sandra for Node B is not free: it takes up network, cpu, and replicated disk space, no?
Lou.

On 2016-11-22 11:10 (-0500), Vladimir Yudovin <v...@winguzone.com> wro= te:
> Hi Lou,>
>
>=
>
> do you mean you set rpc_address (or broadcast_rpc_address) to= Node_B_IP on second machine?>
&g= t;
>
>
> &gt;ther= e would be potential database corruption, no?>
>
<= /div>
> Well, so SSTables are immutable, it = can lead to unpredictable behavior, I guess. I don't believe anybody tested= such setup before.>
>
>
<= div>>
> &gt;Is there any guidance on single instan= ce failover?>
>
> I never saw one, the main Casandra idea that you build multinode cluster.>
>%
=

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