Re: migration from 9.4 to 9.6

El 6/12/19 a las 23:07, Alan Hodgson escribió:
> On Fri, 2019-12-06 at 21:38 +0000, Julie Nishimura wrote:
>> I'd like to copy one single database from 9.4 cluster to a new 9.6 
>> cluster (migration with the upgrade), to the different host
>>
>
> Put 9.4 on the new server. Replicate the db to it. When you're ready 
> to switch, shut down the master, promote the new db, and then shut it 
> down and pg_upgrade -k it to 9.6.
>
> That does require the binaries from both versions to be on the new 
> server for a while, but it'll give you the least downtime and it's a 
> very simple replication setup.


This is the plan we're going to follow to migrate from 9.2 to 9.6, as 
this is the only way to achieve almost zero downtime. The cons are, 
despite what Alan has mentioned, that you need double space because you 
have to create a slave replica.