From user-return-16254-apmail-cassandra-user-archive=cassandra.apache.org@cassandra.apache.org Wed Apr 27 22:02:43 2011 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 1ED332A07 for ; Wed, 27 Apr 2011 22:02:43 +0000 (UTC) Received: (qmail 67903 invoked by uid 500); 27 Apr 2011 22:02:40 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 67866 invoked by uid 500); 27 Apr 2011 22:02:40 -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 67858 invoked by uid 99); 27 Apr 2011 22:02:40 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 27 Apr 2011 22:02:40 +0000 X-ASF-Spam-Status: No, hits=2.2 required=5.0 tests=HTML_MESSAGE,MIME_QP_LONG_LINE,RCVD_IN_DNSWL_NONE,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: local policy) Received: from [208.113.200.5] (HELO homiemail-a44.g.dreamhost.com) (208.113.200.5) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 27 Apr 2011 22:02:32 +0000 Received: from homiemail-a44.g.dreamhost.com (localhost [127.0.0.1]) by homiemail-a44.g.dreamhost.com (Postfix) with ESMTP id 7BA0211805C for ; Wed, 27 Apr 2011 15:02:10 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=thelastpickle.com; h=subject :references:from:content-type:in-reply-to:message-id:date:to :content-transfer-encoding:mime-version; q=dns; s= thelastpickle.com; b=NIRPegoqCtO/cXtubIgYMB0tDBIhFoK9x0k/HBjc8HW 3e+JWRqWqJiZqEffn/1Iu7HR4PVb4Z2TybRFiIajrv/Re/j7RTX83PTQBQeAJek6 IYTZIAf0Ytq9R+MW+0YP0CLOZInXW7Mb9skfTOprN1N6heDjEGCnj0Tzt3OXWBPI = DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=thelastpickle.com; h= subject:references:from:content-type:in-reply-to:message-id:date :to:content-transfer-encoding:mime-version; s=thelastpickle.com; bh=SnOHXUrqC1L4nB+meR+U0fwOQso=; b=qm8qAbt0oAY4xNlUrhCKndJJ8ewJ u5ZVpsfRAPAvdcCxgOqXRmI301Bj2tKCXw41qm5QeCEDkOD7uINuArdVvyJ4Nc+5 PtyH+ZkDgc0ULhTJHRkTHF+MzS6bM1Jv/Lfxr9J+fcMNldwG+uzPsMu2RzXijeUT fG0OcW5SCDupJTs= Received: from [115.189.51.101] (unknown [115.189.51.101]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: aaron@thelastpickle.com) by homiemail-a44.g.dreamhost.com (Postfix) with ESMTPSA id A64CE118057 for ; Wed, 27 Apr 2011 15:02:09 -0700 (PDT) Subject: Re: nodes reference by hostname and not IP References: From: Aaron Morton Content-Type: multipart/alternative; boundary=Apple-Mail-7--782983917 X-Mailer: iPad Mail (8H7) In-Reply-To: Message-Id: <83098214-7A93-4F9F-B6CC-C371A8C7FB1C@thelastpickle.com> Date: Thu, 28 Apr 2011 10:01:57 +1200 To: "user@cassandra.apache.org" Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (iPad Mail 8H7) X-Virus-Checked: Checked by ClamAV on apache.org --Apple-Mail-7--782983917 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii It stores them, but they are not as important as the token. I.e. You can shutdown the node and bring it back on another ip and gossip wi= th sort it out. Aaron On 28/04/2011, at 4:52 AM, Milind Parikh wrote: > =20 > Most likely because in the wild, you can't assume a reliable DNS. > =20 > Just as an aside...This question comes up often in context of managing Cas= sandra clusters;especially in elastic situations. Most CMDBs assume a static= name (host names/static IPs) for nodes. However this often proves to be mis= matched against dynamic systems such as Cassandra; but of course not limited= to it. > =20 > Regards > Milind >=20 > =20 > On Wed, Apr 27, 2011 at 9:37 AM, Sasha Dolgy wrote: > Hi , >=20 > Silly question maybe ... but came to me in the Ec2 thread. Is there a > design reason why cassandra stores nodes as IP addresses and not > hostnames? >=20 > -- > Sasha Dolgy > sasha.dolgy@gmail.com >=20 --Apple-Mail-7--782983917 Content-Transfer-Encoding: 7bit Content-Type: text/html; charset=utf-8
It stores them, but they are not as important as the token.

I.e. You can shutdown the node and bring it back on another ip and gossip with sort it out.

Aaron

On 28/04/2011, at 4:52 AM, Milind Parikh <milindparikh@gmail.com> wrote:

 
Most likely because in the wild, you can't assume a reliable DNS.
 
Just as an aside...This question comes up often in context of managing Cassandra clusters;especially in elastic situations. Most CMDBs assume a static name (host names/static IPs) for nodes. However this often proves to be mismatched against dynamic systems such as Cassandra; but of course not limited to it.
 
Regards
Milind

 
On Wed, Apr 27, 2011 at 9:37 AM, Sasha Dolgy <sdolgy@gmail.com> wrote:
Hi ,

Silly question maybe ... but came to me in the Ec2 thread.  Is there a
design reason why cassandra stores nodes as IP addresses and not
hostnames?

--
Sasha Dolgy
sasha.dolgy@gmail.com

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