[Koha] synchro two instances of Koha

[Francesco Rivetti]

On 2018-03-04 6:07 AM, Giuseppe Angilella wrote:
> is it possible to synchronize two (online) instances of Koha? 

I don't think so.

You could synchronize the two databases (master/master replica)

but I believe Koha (mostly, because of caches) won't like when the data
on its DB is updated by the replica.

It "might" well "enough" though

I mean,
> two identical installations, updated regularly, residing on two 
> different machines, where patrons and administrators can access and 
> modify entries independently. Would it possible to synchronize their 
> databases (and perhaps some relevant external file), on the basis of the 
> modification timestamp of those entries that have been actually modified?

DB replicas (I'm talking about MySQL right now) allow you to synchronize 
two databases both ways, but that doesn't mean the application will be
happy about it.

> (I am not sure whether my question is simply equivalent to that of 
> synchronizing two mysql databases on different servers, for which there 
> might be an answer, if I google it correctly: your advice is appreciated.)

Exactly, but I would rather not go that way.

In the best case scenario, you might have race conditions (two instances 
of Koha trying to change the same row)

It might be worse, the replica might fail, and then the two databases 
will start to drift from each other, and make it really hard to merge 
them together after.

Why would you like to have 2 Master dbs?

F