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From Jonathan Ellis <jbel...@gmail.com>
Subject Re: Extending Ec2Snitch for custom availability zone format
Date Fri, 03 May 2013 01:04:53 GMT
I don't understand what you're trying to solve.  A snitch can get
asked for an endpoint from any DC, so you can't just configure
different nodes with different snitches and figure it will all be
good.

On Thu, May 2, 2013 at 10:35 AM, Ondřej Černoš <cernoso@gmail.com> wrote:
> Hi all,
>
> We use Cassandra in mixed Ec2/OpenStack environment. Unfortunately due to
> decisions made long ago the OpenStack availability zone name obtainable
> through http://169.254.169.254/latest/meta-data/placement/availability-zone is
> not compatible with Cassandra's parsing in o.a.c.locator.Ec2Snitch - the
> format uses dot instead of minus as field separator. Currently I manage my
> own fork of Cassandra's snitches, which is error prone. I thought I might
> patch Cassandra so that it understands custom formats:
>
> - make the format a regex configurable in cassandra.yaml with defaults
> (option not set at all) set to current implementation
> - make it easy - presume three groups (us-east-1a,
> openstack.something-computenode and the like) where the first two groups
> form datacenter name and the last one the rack (plus keeping CASSANDRA-4026
> functionality in place)
>
> For users not configuring the regex nothing will change, others, like me,
> will have the option to parse different availability zone names.
>
> What do you think? Does it have a chance being accepted?
>
> regards,
>
> ondřej černoš



-- 
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder, http://www.datastax.com
@spyced

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