Message-ID: <4CC0C4F3.30501@catalyst.net.nz>
Date: Fri, 22 Oct 2010 11:55:47 +1300
From: Mark Kirkwood <mark.kirkwood@catalyst.net.nz>
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To: pgsql-hackers@postgresql.org
Subject: Re: Simplifying replication
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On 19/10/10 13:16, Josh Berkus wrote:
> Robert asked me to write this up, so here it is.
>
> It is critical that we make replication easier to set up, administrate 
> and monitor than it currently is.  In my conversations with people, 
> this is more important to our users and the adoption of PostgreSQL 
> than synchronous replication is.
>
> First, I'm finding myself constantly needing to tutor people on how to 
> set up replication.  The mere fact that it requires a minimum 1-hour 
> class to explain how to use it, or a 10-page tutoral, tells us it's 
> too complex.  As further evidence, Bruce and I explained binary 
> replication to several MySQL geeks at OpenSQLCamp last weekend, and 
> they were horrified at the number and complexity of the steps 
> required.  As it currently is, binary replication is not going to win 
> us a lot of new users from the web development or virtualization world.
>

+1

I've been having the same experience - how to set this up and do 
failover and failback etc occupies quite a bit of time in courses I've 
been teaching here in NZ and Australia. Having this whole replication 
business much simpler is definitely the way to go.

A good example of how simple it can be is mongodb, where it is 
essentially one command to setup a 2 replica system with a voting arbiter:

$ mongo
 > rs.initiate(
   {
     _id     : "replication_set0",
     members : [
                  { _id  : 0, host : "192.163,2,100" },
                  { _id  : 1, host : "192.168.2.101" },
                  { _id  : 2, host : "192.168.2.103", arbiterOnly : true }
     ]
   }
)