PostgreSQL 添加新节点后的 Citus Shard Rebalancing -> 连接到远程节点 localhost:5432 失败并出现以下错误

Question

Here I have a problem while applying Citus rebalancing after distributing a specific PostgreSQL table and adding new nodes to scale my database.

You can take a look at this useful article if you would like to understand rebalancing in citus before helping out.

In my case I have tried to spread my data to newly added nodes by using citus rebalancing.

So let's assume I have several servers with same credentials and have same databases created. I have assigned one of them as the coordinator node(it will be represented as " 192.168.1.100 " in the example configuration and queries below), and a node that I would like to add to scale my data (will be represented as ( "192.168.1.101" in the example configuration and queries below ).

First of all, I have set the coordinator node by executing the following query.

SELECT citus_set_coordinator_host('192.168.1.100', 5432);

Then, I have distributed my table by

select create_distributed_table('public."Table"','distributedField')

As you may know, For "citus rebalancing" to make sense, we should be capable of rebalancing our data after adding/removing nodes.

SELECT * from citus_add_node('192.168.1.101', 5432);

So we have executed the following query to manage it.

Select * from rebalance_table_shards('public."Table"');

The following error occured every time we tried to execute the query with different configurations or fixes.

connection to the remote node localhost:5432 failed with the following error: fe_sendauth: no password supplied

After hours of research and applying all the suggested solutions in this question , I decided to create a new question to discuss about this.

The system details and configuration files are below.

OS: Ubuntu 20.04.4 LTS

Citus Version: 11.0-2

DB : PostgreSQL 14.4 (Ubuntu 14.4-1.pgdg20.04+1) on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 9.4.0-1ubuntu1~20.04.1) 9.4.0, 64-bit

pg_hba.conf file content:

local   all             postgres                                peer

local   all             all                                     peer

host    all             all             127.0.0.1/32            scram-sha-256

host    all             all             ::1/128                 scram-sha-256

local   replication     all                                     peer
host    replication     all             127.0.0.1/32            scram-sha-256
host    replication     all             ::1/128                 scram-sha-256
host    all             all             192.0.0.0/8             trust

host    all             all             127.0.0.1/32            trust
host    all             all             ::1/128                 trust
host    all             all             192.168.1.101/32        trust

Any help would be appreciated, thanks in advance.

Answer 1

Thank you jjanes.

• I moved trust lines above the scram lines in pg_hba.conf,
  
• Defined a primary key for the distributed table and
  
• set wal_level=logical in the postgresql.conf
  

then my table have been successfully rebalanced now.