There are two Postgres instances running in a Citus cluster:
analysis=# select * from citus_check_cluster_node_health();
from_nodename | from_nodeport | to_nodename | to_nodeport | result
---------------+---------------+-------------+-------------+--------
myhost | 5400 | myhost | 5400 | t
myhost | 5400 | myhost | 5432 | t
myhost | 5432 | myhost | 5400 | t
myhost | 5432 | myhost | 5432 | t
(4 rows)
When trying to rebalance shards in a table:
SELECT * FROM rebalance_table_shards('mydist1');
There is returned an error:
NOTICE: Moving shard 102008 from myhost:5432 to myhost:5400 ...
ERROR: connection to the remote node myhost:5400 failed with the following error: another command is already in progress
CONTEXT: while executing command on localhost:5432
What is the reason of this error?