12 дек. 2014 г., в 16:46, Heikki Linnakangas <hlinnakan...@vmware.com> 

> There have been a few threads on the behavior of WAL archiving, after a 
> standby server is promoted [1] [2]. In short, it doesn't work as you might 
> expect. The standby will start archiving after it's promoted, but it will not 
> archive files that were replicated from the old master via streaming 
> replication. If those files were not already archived in the master before 
> the promotion, they are not archived at all. That's not good if you wanted to 
> restore from a base backup + the WAL archive later.
> The basic setup is a master server, a standby, a WAL archive that's shared by 
> both, and streaming replication between the master and standby. This should 
> be a very common setup in the field, so how are people doing it in practice? 
> Just live with the wisk that you might miss some files in the archive if you 
> promote? Don't even realize there's a problem? Something else?

Yes, I do live like that (with streaming replication and shared archive between 
master and replicas) and don’t even realize there’s a problem :( And I think 
I’m not the only one. Maybe at least a note should be added to the 

> And how would we like it to work?
> There was some discussion in August on enabling WAL archiving in the standby, 
> always [3]. That's a related idea, but it assumes that you have a separate 
> archive in the master and the standby. The problem at promotion happens when 
> you have a shared archive between the master and standby.

AFAIK most people use the scheme with shared archive.

> [1] 
> http://www.postgresql.org/message-id/CAHGQGwHVYqbX=a+zo+avfbvhlgoypo9g_qdkbabexgxbvgd...@mail.gmail.com
> [2] http://www.postgresql.org/message-id/20140904175036.310c6466@erg
> [3] 
> http://www.postgresql.org/message-id/CAHGQGwHNMs-syU=mevsesthna+exd9pfo_ohhfpjcwovayr...@mail.gmail.com.
> - Heikki
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