Re: [Postgres-xc-general] DROP NODE

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Hi. I decided to modify my configuration like this:

Node A: 1 gtm master
Node B: 1 gtm_proxy,

1 coordinator master, 1 coordinator slave (for node C coordinator),
1 datanode master, 1 datanode slave (for node C data node)

Node C: 1 gtm_proxy,

1 coordinator master, 1 coordinator slave (for node B coordinator),
1 datanode master, 1 datanode slave (for node B data node)

Node D: 1 gtm slave

I added following lines in postgresql.conf of each data node slave.
pgxc_ctl script didn't add them.

archive_mode = off
archive_command = ''
max_wal_senders = 0
wal_level = minimal

In normal operation, everything worked fine.

Fist I killed data node master in Node B, I promoted corresponding data
node slave to master with pgxc_ctl. I got the following error:

ERROR:  PGXC node datanode1: two nodes cannot be primary
 pgxc_pool_reload
------------------
 t
(1 row)

ERROR:  PGXC node datanode1: two nodes cannot be primary
 pgxc_pool_reload
------------------
 t
(1 row)

In both master coordinators, I queried pgxc_node and the failed datanode
still pointed to node B. I had to execute ALTER NODE for change host and
primary property. After that, everything worked fine.

Then, I killed coordinator master in Node B, I promoted corresponding
coordinator slave to master. I got the following results:

ALTER NODE
 pgxc_pool_reload
------------------
 t
(1 row)

ERROR:  Failed to get pooled connections
CONTEXT:  SQL statement "EXECUTE DIRECT ON (coord1) 'SELECT
pg_catalog.pg_try_advisory_xact_lock_shared(65535, 0)'"
 pgxc_pool_reload
------------------
 t
(1 row)

So in new master coordinator, when I queried pgxc_node the failed
coordinator pointed correctly to node C. But in the original master
coordinator of node C, when I queried pgxc_node the failed coordinator
pointed to node B. In this coordinator I tried to modify failed coordinator
with ALTER NODE but I got the same error Failed to get pooled connections.

Finally when I execute ALTER TALBE … DELETE NODE for a table, in the new
master coordinator it executed ok. But in the original master coordinator
of node C I got the same error Failed to get pooled connections.

Is this behaviour normal? What can i do?

2014-04-02 23:19 GMT-05:00 鈴木 幸市 <ko...@in...>:

>  Before removing a datanode, you should drop the datanode from tables
> before you drop the datanode.   You can do this with ALTER TALBE … DELETE
> NODE as seen in
> http://postgres-xc.sourceforge.net/docs/1_1/sql-altertable.html.   This
> will extract all the rows from the node and redistribute them (as well as
> others) to the new set of nodes.
>
>  List of the nodes where a table is distributed/replicated in pgxc_class.
>
>  Regards;
> ---
> Koichi Suzuki
>
>  2014/04/02 15:06、Sergio Sinuco <ser...@da...> のメール：
>
>  I use pgxc_ctl.
>
>  My configuration is:
>
>  Node A: 1 gtm master
> Node B: 1 gtm_proxy, 1 coordinator, 1 datanode
> Node C: 1 gtm_proxy, 1 coordinator, 1 datanode
>  Node D: 1 gtm slave
>
>  First I stopped coordinator and data node from Node C. Then I executed*
> pgxc_ctl remove datanode.... *and *pgxc_ctl remove coordinator...* were
> ok. But I got "Failed to get pooled connections" message when I tried an
> insert or update in Node B. I also ran pgxc_pool_reload and restarted the
> cluster. If I run "SELECT * FROM pgxc_node" in Node B I only have one
> coordinator and one data node.
>
>  The inserts and update commands was ran in a DISTRIBUTE BY REPLICATION
> table.
>
>
>
> 2014-04-02 0:32 GMT-05:00 鈴木 幸市 <ko...@in...>:
>
>> Did you change your cluster configuration?   Are you using pgxc_ctl or
>> doing configuration/operation manually?
>>
>>  They help to see what’s going on.
>>
>>  Thank you;
>> ---
>> Koichi Suzuki
>>
>>  2014/04/02 14:02、Sergio Sinuco <ser...@da...> のメール：
>>
>>   Hi. I dropped a coordinator node and a data node from a cluster, but
>> when i try to make an insert or update I have a "Failed to get pooled
>> connections" message. I executed pgxc_pool_reload() but it didn't work.
>> What can I do? I use pgxc 1.1.
>>
>> --
>> Sergio E. Sinuco Leon
>> Arquitecto de soluciones
>> Datatraffic S.A.S.
>> Móvil: (57) 310 884 26 50
>> Fijo (+571) 7426160 Ext 115
>> Calle 93 # 15-27 Ofc. 502
>> Calle 29 # 6 - 94 Ofc. 601
>> Bogotá, Colombia.
>> www.datatraffic.com.co
>>
>> ------------------------------------------------------------------------------
>> _______________________________________________
>> Postgres-xc-general mailing list
>> Pos...@li...
>> https://lists.sourceforge.net/lists/listinfo/postgres-xc-general
>>
>>
>>
>
>
>  --
> Sergio E. Sinuco Leon
> Arquitecto de soluciones
> Datatraffic S.A.S.
> Móvil: (57) 310 884 26 50
> Fijo (+571) 7426160 Ext 115
> Calle 93 # 15-27 Ofc. 502
> Calle 29 # 6 - 94 Ofc. 601
> Bogotá, Colombia.
> www.datatraffic.com.co
>
>
>

-- 
Sergio E. Sinuco Leon
Arquitecto de soluciones
Datatraffic S.A.S.
Móvil: (57) 310 884 26 50
Fijo (+571) 7426160 Ext 115
Calle 93 # 15-27 Ofc. 502
Calle 29 # 6 - 94 Ofc. 601
Bogotá, Colombia.
www.datatraffic.com.co