Обсуждение: BDR: moving a node

Hello,

As a preamble, I'm running PostgreSQL 9.4 BDR on a Debian 9.

I'm moving a node to a new host. This is the node from which I started 
BDR and had a second replicate join it.

I browsed the list archive, Googled all I could, found some threads and 
Github issues, but came up with a grant total of no concrete answers.

When I say "moving", I mean I'm copying the entire filesystem with 
PostgreSQL shut down, so I assume my data integrity is taken care of. 
All I imagine I need to do is replace the DSN on the second node, which 
in my carelessness, I set up using an IP address and not an FQDN.
I looked up Node Management Functions in the doc,   but cannot come up 
with the final set of instructions to perform an update of the DSN.

What is the process to update the DSN? I assume I'll have to relay the 
changes in my pg_hba.conf, but do not understand, and don't want to 
tinker, with BDR before obtaining some educated advice.

I apologize if my question comes across as dumb. I understand I have to 
update bdr.bdr_connections, but how, and what do I restart? What about 
the server that was moved, any updates needed there?

thanks for your help!

Am 25.08.19 um 18:11 schrieb E:
> What is the process to update the DSN? I assume I'll have to relay the 
> changes in my pg_hba.conf, but do not understand, and don't want to 
> tinker, with BDR before obtaining some educated advice.
>
> I apologize if my question comes across as dumb. I understand I have 
> to update bdr.bdr_connections, but how, and what do I restart? What 
> about the server that was moved, any updates needed there?

the safest way would be to part that node from the cluster and rejoin it 
afterwards.

You have (at least) to check all replication slots, please check also 
pg_replication_identifier (please use pg_replication_identifier_drop() 
to drop the node ) , bdr.bdr_nodes and bdr.bdr_connections. Please keep 
in mind, BDR version 1 will be out of support soon, and PG 9.4 as well. 
Current development of BDR is BDR 3.6.x., it works with PG 10+ .



Regards, Andreas

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