Re: streaming replication + wal shipping

Thanks for your response.

So are you saying that if I setup the following in my recovery.conf
restore_command =.....

It will it be used only when the streaming replication falls behind more than ( wal_keep_segments ) or replication stream is not available (master goes down) ?

Thanks for your help.

On Monday, April 14, 2014 1:35 PM, Albe Laurenz <laurenz(dot)albe(at)wien(dot)gv(dot)at> wrote:

Anupama Ramaswamy wrote:

> I would like to setup a 2 servers with streaming replication, one master and another hot standby.
> I want to use the standby for read-only queries. So I want the replication lag to be as small as
> possible.
> So I choose streaming replication over WAL shipping.
>
> When the master fails, I want the standby to take over as master. So I would like minimal data loss,
> if there is a streaming replication delay.
>
> Is it possible to setup such a way that under normal conditions the standby by replicating using
> streaming replication and on failover, it uses the WAL archive for syncing up with the transactions.
> Of course the WAL will be available on a shared storage volume. If this is possible, what exactly do I
> need in my configuration files - postgresql.conf, recovery.conf ?

Most of this will happen automatically - WAL archives are used if recovery
falls behind.

Where you will need additional software is automatic failover; you need some
OS cluster software that can detect failure and automatically promote the standby.

Yours,
Laurenz Albe